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. Modeling and predicting the structure of transmembrane proteins - - PowerPoint PPT Presentation

. Modeling and predicting the structure of transmembrane proteins uhl 123 , Jean-Marc Steyaert 2 J er ome Waldisp Jerome.Waldispuhl@polytechnique.edu 1 Department of Biology, Boston College, USA 2 LIX, Ecole polytechnique, France 3


slide-1
SLIDE 1

. Modeling and predicting the structure of transmembrane proteins

J´ erˆ

  • me Waldisp¨

uhl 123, Jean-Marc Steyaert 2

Jerome.Waldispuhl@polytechnique.edu

1 Department of Biology, Boston College, USA 2 LIX, ´

Ecole polytechnique, France

3 LIAFA, Universit´

e de Paris 7, France

TMMTSAG – p. 1/62

slide-2
SLIDE 2

Objectives

Modeling and predicting the structure

  • f transmembrane proteins

Introduction – p. 2/62

slide-3
SLIDE 3

Outlines

Summary of language theory (multi-tape S-attribute grammars), some notions of biology, an approximate physical model, grammatical modeling, performance evaluation, conclusion.

Introduction – p. 3/62

slide-4
SLIDE 4

S-attribute grammars

Definition Context-free grammars G = {VT, VN, P, S} VT is the set of terminals, VN is the set of non-terminals, P is the set of productions rules (A → α), S is the axiom,

Language theory – p. 4/62

slide-5
SLIDE 5

S-attribute grammars

Definition S-attribute grammars G = {VT, VN, P, S, A, λA, FP} VT is the set of terminals, VN is the set of non-terminals, P is the set of productions rules, S is the axiom, A is the set of attributes, λA is the set of evaluation functions for the terminals, FP is the set of the fonctions used to compute the non-terminals attributes.

Language theory – p. 4/62

slide-6
SLIDE 6

Example (1) : arithmetical expressions

VT = {0, · · · , 9, +, ×}, VN = S, P =

      

S → S + S S → S × S S → 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9

        

Context-free grammar

Language theory – p. 5/62

slide-7
SLIDE 7

Example (1) : arithmetical expressions

VT = {0, · · · , 9, +, ×}, VN = S, P =

      

S → S + S S → S × S S → 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9

        

Context-free grammar A = N λA =

            

SA(0) = 0 . . . SA(9) = 9 SA(+, ×) = 0 FP =

      

fS→S+S(xyz) = x + z fS→S×S(xyz) = x × z fS→a∈VT (x) = x

                

Attribute system

Language theory – p. 5/62

slide-8
SLIDE 8

Exemple (1) : Arithmetical expressions

8 × 9 + 5

Language theory – p. 6/62

slide-9
SLIDE 9

Exemple (1) : Arithmetical expressions

8 × 9 + 5 8 S × 9 S S + 5 S S

Language theory – p. 6/62

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SLIDE 10

Exemple (1) : Arithmetical expressions

8 × 9 + 5 8,8 S ×,0 9,9 S S +,0 5,5 S S

Language theory – p. 6/62

slide-11
SLIDE 11

Exemple (1) : Arithmetical expressions

8 × 9 + 5 8,8 S,8 ×,0 9,9 S,9 S,72 +,0 5,5 S,5 S,77

Language theory – p. 6/62

slide-12
SLIDE 12

Exemple (1) : Arithmetical expressions

8 × 9 + 5 8,8 S,8 ×,0 9,9 S,9 S,72 +,0 5,5 S,5 S,77 8 S × 9 S + 5 S S S

Language theory – p. 6/62

slide-13
SLIDE 13

Exemple (1) : Arithmetical expressions

8 × 9 + 5 8,8 S,8 ×,0 9,9 S,9 S,72 +,0 5,5 S,5 S,77 8,8 S,8 ×,0 9,9 S,9 +,0 5,5 S,5 S,14 S,112

Language theory – p. 6/62

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SLIDE 14

Exemple (1) : Arithmetical expressions

8 × 9 + 5 8,8 S,8 ×,0 9,9 S,9 S,72 +,0 5,5 S,5 S,77 8,8 S,8 ×,0 9,9 S,9 +,0 5,5 S,5 S,14 S,112 ...Only the derivation tree with the optimal attribute is conserved.

Language theory – p. 6/62

slide-15
SLIDE 15

Optimization constraint

Definition Optimization constraint C(x, λx, y, λy) x and y ∈ VT ∪ VN, λx and λx ∈ A, return the pair (z, λz) such that λz is optimal.

Language theory – p. 7/62

slide-16
SLIDE 16

Example (2) : RNA secondary structure

G G G A U A U A C G

G A A G G G U U A C H,0 H,0 H,0 L,1 L,2 B,2 L,3

Language theory – p. 8/62

slide-17
SLIDE 17

Example (2) : RNA secondary structure

G G G A U A U A C G

G A A G G G U U A C H,0 H,0 H,0 L,1 L,2 B,2 L,3

secondary structure = derivation tree folding energy = attributes secondary structure with the minimum free energy (Zuker) = derivation tree with the optimal attribute

Language theory – p. 8/62

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SLIDE 18

S-attribute grammars

How to find the optimal derivation tree ?

principle : dynamic programming algorithm : Cocke-Kazamy-Younger, Earley, GCP ... implementation : mtsag2c (F . Lefebvre, 1997)

Language theory – p. 9/62

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SLIDE 19

Multi-tape S-attribute grammar

Definition Multi-tape alphabet Σ =

  • i=1···m

(Σ(i) ∪ {ε}) Definition Multi-tape Context-free grammar G = {VT, VN, P, S} where VT is an m-tape alphabet. Definition Multi-tape S-attribute grammar G = {VT, VN, P, S, A, λA, FP} where VT is an m-tape alphabet.

Language theory – p. 10/62

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SLIDE 20

Example : RNA sequence alignment

                                    

S → SS | mat | del | ins | mut mat →

a

a

  • | u

u

  • | g

g

  • | c

c

  • del

a

  • | −

u

  • | −

g

  • | −

c

  • ins

a

  • | u

  • | g

  • | c

  • mut

a

u

  • | a

g

  • | a

c

  • | u

a

  • | u

g

  • | u

c

  • | g

a

  • | g

u

  • | g

c

  • | c

a

  • | c

u

  • | c

g

  • Language theory – p. 11/62
slide-21
SLIDE 21

Example : RNA sequence alignment

                                    

S → SS | mat | del | ins | mut mat →

a

a

  • | u

u

  • | g

g

  • | c

c

  • del

a

  • | −

u

  • | −

g

  • | −

c

  • ins

a

  • | u

  • | g

  • | c

  • mut

a

u

  • | a

g

  • | a

c

  • | u

a

  • | u

g

  • | u

c

  • | g

a

  • | g

u

  • | g

c

  • | c

a

  • | c

u

  • | c

g

  • A = Z

λ(•) = 0 FP =

                

fS→SS(xy) = x + y fS→del|ins|mut(x) = x fmat→•(x) = fdel→•(x) = 1 fins→•(x) = 1 fmut→•(x) = 1

Language theory – p. 11/62

slide-22
SLIDE 22

Example : RNA sequence alignment

S,5 S,0

mat,0

a

a

  • S,5

S,0

mat,0

c

c

  • S,5

S,1

del,1

c

  • S,4

S,0

mat,0

u

u

  • S,4

S,1

mut,1

  • u

g

  • S,3

S,0

mat,0

  • g

g

  • S,3

S,1

ins,1

  • c

  • S,2

S,0

mat,0

a

a

  • S,2

S,0

mat,0

u

u

  • S,2

S,1

del,1

g

  • S,1

S,1

mut,1

a

u

  • S,0

mat,0

c

c

  • Language theory – p. 12/62
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SLIDE 23

Notions of biology

Notions of Biology

Definition of a protein Structure of proteins Transmembrane channels

Notions of biology – p. 13/62

slide-24
SLIDE 24

Definition of a protein

Amino acid chemical formula :

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− R NH+

3

H

Notions of biology – p. 14/62

slide-25
SLIDE 25

Definition of a protein

The 20 amino acids :

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− H NH+

3

H

✂ ✄ ☎✆ ✝ ✞
✂ ✟
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− CH3 NH+

3

H

✡ ✁ ☛ ✆ ☎ ✆ ✝ ✞ ✡ ✁ ☛ ✟ ✡ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH CH3 CH3

☞ ☛ ✁ ☎ ✆ ✝ ✞ ☞ ☛ ✁ ✟ ☞ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH CH3 CH3

✌ ✝✍ ✄ ☎ ✆ ✝ ✞ ✌ ✝✍ ✟ ✌ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

C CH3 H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2 CH3

✎ ✏✑ ✁ ✝ ✍ ✄ ☎ ✆ ✝ ✞ ✎ ✁ ✝ ✟ ✌ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2 OH

✒ ✝✓ ☎ ✆ ✝ ✞ ✒ ✝ ✓ ✟ ✒ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

C OH CH3 H

✔ ✕ ✓ ✝ ✑ ✆ ☎ ✆ ✝ ✞ ✔ ✕ ✓ ✟ ✔ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ✖ ✕ ✝ ✆ ✂ ✁ ☛ ✁ ☛ ✆ ☎✆ ✝ ✞ ✖ ✕ ✝ ✟ ✗ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OH

. . . . . . . . . . . . . . . . . . . . . . . . . . . . ✔ ✂ ✓ ✑ ✏ ☎ ✆ ✝ ✞ ✔ ✂ ✓ ✟ ✘ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

C

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH NH

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ✔ ✓ ✂ ✙ ✚ ✑ ✙ ✕ ☛ ✆ ✝ ✞ ✔ ✓ ✙ ✟ ✛ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2 NH+

3

✌ ✂ ✏ ☎✆ ✝ ✞ ✌ ✂ ✏ ✟ ✜ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

C NH2 NH2

✡ ✓ ✢ ☎ ✆ ☎ ✆ ✝ ✞ ✡ ✓ ✢ ✟ ✣ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH N CH C NH

✤ ☎ ✏ ✚ ☎✥ ☎ ✆ ✝ ✞ ✤ ☎ ✏ ✟ ✤ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2 COO−

✡ ✏ ✙ ☛ ✓ ✚ ☛ ✚ ✝ ✞ ✡ ✏ ✙ ✟ ✦ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2 COO−

✍ ✚ ☛✧ ☛ ✚ ✝ ✞
✍ ✟ ★ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2 O NH2

✡ ✏ ✙ ☛ ✓ ☛ ✢ ☎ ✆ ✝ ✞ ✡ ✏ ✆ ✟ ✩ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2 O NH2

✍ ✚ ☛✧ ☛✧ ☎ ✆ ✝ ✞
✆ ✟ ✪ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2 SH

✫ ✂ ✏ ✚✬ ☎ ✆ ✝ ✞ ✫ ✂ ✏ ✟ ✫ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

S CH3

✭ ✬ ✚ ✕ ☎ ✑ ✆ ☎✆ ✝ ✞ ✭ ✝ ✚ ✟ ✭ ✠ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

NH+

2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CH2 CH2 CH2 COO−

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . . ✖ ✓ ✑ ✁ ☎ ✆ ✝ ✞ ✖ ✓ ✑ ✟ ✖ ✠

Notions of biology – p. 14/62

slide-26
SLIDE 26

Definition of a protein

The peptid bond :

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− R1 NH+

3

H

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− R2 NH+

3

H

Notions of biology – p. 14/62

slide-27
SLIDE 27

Definition of a protein

The peptid bond :

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα R1 NH+

3

H CONH

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cα COO− R2 H

· · · + H2O

Notions of biology – p. 14/62

slide-28
SLIDE 28

Structure of proteins

Kynase C

Notions of biology – p. 15/62

slide-29
SLIDE 29

α-helix

α-helix

3.6 amino acids per turn, hydrogen bond between residus n and n + 4.

Notions of biology – p. 16/62

slide-30
SLIDE 30

β-sheet

β-sheet

composed of β-strands 2 amino acids per turn, hydrogen bond between residues of paired β-strands.

Notions of biology – p. 17/62

slide-31
SLIDE 31

Transmembrane channels

Bacteriorhodopsin Porin

Notions of biology – p. 18/62

slide-32
SLIDE 32

Transmembrane channels

Bacteriorhodopsin Porin

Notions of biology – p. 18/62

slide-33
SLIDE 33

Transmembrane channel

Why ?

Notions of biology – p. 19/62

slide-34
SLIDE 34

Transmembrane channel

Why ? Simple topologies (only parallel or anti-parallel pairings), strong contraints from the environment, Some parameters are (much) more important than the others (hydrophobicity)

Notions of biology – p. 19/62

slide-35
SLIDE 35

Transmembrane channel

Why ? Simple topologies (only parallel or anti-parallel pairings), strong contraints from the environment, Some parameters are (much) more important than the others (hydrophobicity) Interest ?

Notions of biology – p. 19/62

slide-36
SLIDE 36

Transmembrane channel

Why ? Simple topologies (only parallel or anti-parallel pairings), strong contraints from the environment, Some parameters are (much) more important than the others (hydrophobicity) Interest ? nearly 40% of the proteome, functional importance (allows communication between inner and outer milieu of cell), difficult to be observe experimentaly.

Notions of biology – p. 19/62

slide-37
SLIDE 37

Approximate physical model for transmembrane channels

Approximate physical model for α-transmembrane channels

Modeling the overall structure of α-channel, modeling anti-parallel pairing of α-helices, modeling the local structure of α-helices, pseudo folding energy of α-channels.

Approximate physical model – p. 20/62

slide-38
SLIDE 38

Modeling the overall structure of α-channel

Approximate physical model – p. 21/62

slide-39
SLIDE 39

Modeling the overall structure of α-channel

Approximate physical model – p. 21/62

slide-40
SLIDE 40

Modeling the overall structure of α-channel

Approximate physical model – p. 21/62

slide-41
SLIDE 41

Modeling the overall structure of α-channel

Approximate physical model – p. 21/62

slide-42
SLIDE 42

Modeling the overall structure of α-channel

Approximate physical model – p. 22/62

slide-43
SLIDE 43

Modeling the overall structure of α-channel

Approximate physical model – p. 22/62

slide-44
SLIDE 44

Modeling the overall structure of α-channel

Description of α-channels with only simple anti-parallel pairings.

Approximate physical model – p. 22/62

slide-45
SLIDE 45

Modeling the overall structure of α-channel

An α-channel is a concatenation of simple anti-parallel pairings.

Approximate physical model – p. 22/62

slide-46
SLIDE 46

Modeling anti-parallel pairing of α-helices

Let’s go back to a linear description :

Approximate physical model – p. 23/62

slide-47
SLIDE 47

Modeling anti-parallel pairing of α-helices

Let’s go back to a linear description :

Approximate physical model – p. 23/62

slide-48
SLIDE 48

modeling anti-parallel pairing of α-helices

Approximate physical model – p. 24/62

slide-49
SLIDE 49

modeling anti-parallel pairing of α-helices

Approximate physical model – p. 24/62

slide-50
SLIDE 50

modeling anti-parallel pairing of α-helices

I O I O I O I O O I O I O I O I

Approximate physical model – p. 24/62

slide-51
SLIDE 51

Modeling the local structure of α-helices

O I

✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁

A helix is a stacking of helix turns, A helix turn is a sequence of resi- dues corresponding to a complete turn around the helix axis, A helical face is a subsequence of consecutive amino acids of a helix turn,

face I is involved in pairing, face O is opposed to pairing.

Approximate physical model – p. 25/62

slide-52
SLIDE 52

Modeling the local structure of α-helices

O I

✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁

I O I O I I O O I I O O

Approximate physical model – p. 25/62

slide-53
SLIDE 53

Modeling the local structure of α-helices

O I

✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁

A helix is an alternate sequence of residues belonging to a I or O face, A helix turn is composed by 3 or 4 consecutive amino acids, A helical face has 1 or 2 amino acids, On average, 3.6 residus per turn.

Approximate physical model – p. 25/62

slide-54
SLIDE 54

Pseudo folding energy

MEMBRANE MEMBRANE 2 1 2 3 EXTERIEUR

Approximate physical model – p. 26/62

slide-55
SLIDE 55

Pseudo folding energy

MEMBRANE MEMBRANE 2 1 2 3 EXTERIEUR

  • 1. Econtact residu interaction

energy, Econtact =

n

  • i=0

f(Ik

i , Ik+1 i

), où f(Ik

i , Ik+1 i

) =

  • ωj∈Ik

i

·

  • ωj′∈Ik+1

i

λj · λj′

  • #Ik

i · #Ik+1 i

Approximate physical model – p. 26/62

slide-56
SLIDE 56

Pseudo folding energy

MEMBRANE MEMBRANE 2 1 2 3 EXTERIEUR

  • 1. Econtact residu interaction

energy,

  • 2. Ememb membrane interaction

energy, Ememb =

  • ωi∈Ok

i

Kmemb · λi

Approximate physical model – p. 26/62

slide-57
SLIDE 57

Pseudo folding energy

MEMBRANE MEMBRANE 2 1 2 3 EXTERIEUR

  • 1. Econtact residu interaction

energy,

  • 2. Ememb membrane interaction

energy,

  • 3. Eturn turn energy.

Eturn = T (n − m) +

n

  • i=m

Kcyt/per · λi

Approximate physical model – p. 26/62

slide-58
SLIDE 58

Modeling the overall structure of α-channel

Approximate physical model – p. 27/62

slide-59
SLIDE 59

Modeling the overall structure of α-channel

Approximate physical model – p. 28/62

slide-60
SLIDE 60

Modeling the overall structure of α-channel

Approximate physical model – p. 28/62

slide-61
SLIDE 61

Modeling the overall structure of α-channel

A β-channel is a concatenation of anti-parallel pairings of β-strands.

Approximate physical model – p. 28/62

slide-62
SLIDE 62

Grammatical modeling

Grammatical modeling of Transmembrane channels

Local structure of the secondary structures : rational grammar Secondary structure pairing : context-free grammar Overall structure of a TM channel : multi-tape context-free grammar pseudo folding energy : attributes

Grammatical modeling – p. 29/62

slide-63
SLIDE 63

MTCFG des canaux α

Grammatical modeling of TM α-channels

Regular grammar for α-helix, Context-free grammar for α-helix pairings, Multi-tape context-free grammar for α-channel, Muti-tape S-attribute grammar for α-channel,

Grammatical modeling – p. 30/62

slide-64
SLIDE 64

Regular grammar for α-helix

A helix is an alternate se- quence of residues belon- ging to a I or O face, A helix turn is composed by 3 or 4 consecutive amino acids, A helical face has 1 or 2 amino acids, On average, 3.6 residus per turn. Phelice =

                  

Shelice → I0 | I1 | O0 | O1 I0 → • I1 | • O0 I1 → • O0 | • O1 O0 → • O1 O1 → • I0

Grammatical modeling – p. 31/62

slide-65
SLIDE 65

Regular grammar for α-helix

A helix is an alternate se- quence of residues belon- ging to a I or O face, A helix turn is composed by 3 or 4 consecutive amino acids, A helical face has 1 or 2 amino acids, On average, 3.6 residus per turn. I0 I1 O0 O1

Grammatical modeling – p. 31/62

slide-66
SLIDE 66

CFG for α-helix anti-parallel pairings

I O I O I O I O O I O I O I O I

Grammatical modeling – p. 32/62

slide-67
SLIDE 67

CFG for α-helix anti-parallel pairings

I O I O I O I O O I O I O I O I

Pap =

                  

ap

→ F α

O | F α I

F α

I

→ I F α

O I | Cα cyt | Cα per

F α

O

→ O F α

I O | Cα cyt | Cα per

cyt

→ i Cα

cyt | i

per

per | o

Grammatical modeling – p. 32/62

slide-68
SLIDE 68

CFG for α-helix anti-parallel pairings

Pap =

                  

ap

→ F α

O | F α I

F α

I

→ I F α

O I | Cα cyt | Cα per

F α

O

→ O F α

I O | Cα cyt | Cα per

cyt

→ i Cα

cyt | i

per

per | o

Grammatical modeling – p. 32/62

slide-69
SLIDE 69

CFG for α-helix anti-parallel pairings

Pap =

                  

ap

→ F α

O | F α I

F α

I

→ I F α

O I | Cα cyt | Cα per

F α

O

→ O F α

I O | Cα cyt | Cα per

cyt

→ i Cα

cyt | i

per

per | o

Phelice =

              

Shelice → I0 | I1 | O0 | O1 I0 → • I1 | • O0 I1 → • O0 | • O1 O0 → • O1 O1 → • I0

Grammatical modeling – p. 32/62

slide-70
SLIDE 70

CFG for α-helix anti-parallel pairings

P α

ap =

                                                          

Sap → F 1,1

I

| F 1,1

O

1 F 1,1

I

  • • F 1,1

O

  • • | • F 2,1

O

  • • | • • F 1,2

O

  • | • F 1,1

O

  • | Cα

cyt

2 F 2,1

I

  • • F 1,1

O

  • • | • • F 1,2

O

  • | Cα

cyt

3 F 1,2

I

  • • F 1,1

O

  • • | • F 2,1

O

  • • | Cα

cyt

4 F 2,2

I

  • • F 2,2

O

  • • | Cα

cyt

5 F 1,1

O

  • • F 1,1

I

  • • | • F 2,1

I

  • • | • • F 1,2

I

  • | • F 2,2

I

  • | Cα

cyt

6 F 2,1

O

  • • F 1,1

I

  • • | • • F 1,2

I

  • | Cα

cyt

7 F 1,2

O

  • • F 1,1

I

  • • | • F 2,1

I

  • • | Cα

cyt

8 F 2,2

O

  • • F 1,1

I

  • • | Cα

cyt

9 Cα

cyt

cyt | •

10

Grammatical modeling – p. 33/62

slide-71
SLIDE 71

MTCFG for α-channels

A TM-channel is represented by a 2-tape word : ))))))iii))))))oo))))))ii))))))ooo)))))) ((((((iii((((((oo((((((ii((((((ooo((((((

Grammatical modeling – p. 34/62

slide-72
SLIDE 72

MTCFG for α-channels

A TM-channel is represented by a 2-tape word : ))))))------iii))))))------oo))))))------ii))))))------

  • -----((((((iii------((((((oo------((((((ii------((((((

Grammatical modeling – p. 34/62

slide-73
SLIDE 73

MTCFG for α-channels

Pcanal =

                                                  

Sα →

t)

t(

  • | T α

seq,cyt | T α seq,per

1 T α

seq,cyt

→ T α

cyt T α seq,per | T α cyt

2 T α

seq,per

→ T α

per T α seq,cyt | T α per

3 T α

cyt

t(

  • T α

cyt

t)

  • | Cα

cyt

4 T α

per

t(

  • T α

per

t)

  • | Cα

per

5 Cα

cyt

i

i

cyt | i i

  • 6

per

per | o

  • 7

Grammatical modeling – p. 35/62

slide-74
SLIDE 74

MTCFG for α-channels

t(

t(

t(

t(

t(

T α

seq,cyt

T α

cyt

t(

  • T α

cyt

t(

  • T α

cyt

t(

  • T α

cyt

t(

  • T α

cyt

t(

cyt

i

i

cyt

i

i

t)

t)

t)

t)

t)

  • T α

seq,per

T α

per

t(

  • T α

per

t(

  • T α

per

t(

  • T α

per

t(

  • T α

per

t(

per

per

per

  • t)

t)

t)

t)

t)

  • T α

seq,cyt

T α

cyt

t(

  • T α

cyt

t(

  • T α

cyt

t(

  • T α

cyt

t(

  • T α

cyt

t(

cyt

i

i

cyt

i

i

t)

t)

t)

t)

t)

t)

t)

t)

t)

t)

  • Grammatical modeling – p. 36/62
slide-75
SLIDE 75

MTCFG for α-channels

How to integrate the pairing rules ?

))))iii))))oo))))ii))))oo)))) ((((iii((((oo((((ii((((oo((((

Grammatical modeling – p. 37/62

slide-76
SLIDE 76

MTCFG for α-channels

How to integrate the pairing rules ?

MPPMMPMMPPMMiiiPPMPPMMPMMPPooMMPPMMPMMPMMiiPPMPPMMPMMPPooMMPMMPMMPPMM PMMPPMMPPMMPiiiMPPMMPMMPPMMooPMMPPMPPMMPPiiMPPMMPPMMPPMooMPPMMPPMPPMM

Grammatical modeling – p. 37/62

slide-77
SLIDE 77

MTCFG for α-channels

P α

ap =

                                                          

Sap → F 1,1

I

| F 1,1

O

1 F 1,1

I

  • • F 1,1

O

  • • | • F 2,1

O

  • • | • • F 1,2

O

  • | • F 1,1

O

  • | Cα

2 F 2,1

I

  • • F 1,1

O

  • • | • • F 1,2

O

  • | Cα

3 F 1,2

I

  • • F 1,1

O

  • • | • F 2,1

O

  • • | Cα

4 F 2,2

I

  • • F 2,2

O

  • • | Cα

5 F 1,1

O

  • • F 1,1

I

  • • | • F 2,1

I

  • • | • • F 1,2

I

  • | • F 2,2

I

  • | Cα

6 F 2,1

O

  • • F 1,1

I

  • • | • • F 1,2

I

  • | Cα

7 F 1,2

O

  • • F 1,1

I

  • • | • F 2,1

I

  • • | Cα

8 F 2,2

O

  • • F 1,1

I

  • • | Cα

9 Cα →

  • Cα | •

10

Grammatical modeling – p. 38/62

slide-78
SLIDE 78

MTCFG for α-channels

P α =

                                                  

Sα →

  • ε
  • ε
  • | Canal

1 Canal → F 1,1

I

Canal | F 1,1

O

Canal | F 1,1

I

| F 1,1

O

2 F 1,1

I

  • ε
  • ε
  • F 1,1

O

  • ε
  • ε
  • |

ε

  • F 2,1

O

  • ε
  • ε
  • |

ε

  • ε
  • F 1,2

O

  • ε
  • |

ε

  • F 2,2

O

  • ε
  • | Cα

3 F 2,1

I

  • ε
  • ε
  • F 1,1

O

  • ε
  • ε
  • |

ε

  • ε
  • F 1,2

O

  • ε
  • | Cα

4 F 1,2

I

  • ε
  • ε
  • F 1,1

O

  • ε
  • ε
  • |

ε

  • F 2,1

O

  • ε
  • ε
  • | Cα

5 F 2,2

I

  • ε
  • ε
  • F 1,1

O

  • ε
  • ε
  • | Cα

6 F 1,1

O

  • ε
  • ε
  • F 1,1

I

  • ε
  • ε
  • |

ε

  • F 2,1

I

  • ε
  • ε
  • |

ε

  • ε
  • F 1,2

I

  • ε
  • |

ε

  • F 2,2

I

  • ε
  • | Cα

7 F 2,1

O

  • ε
  • ε
  • F 1,1

I

  • ε
  • ε
  • |

ε

  • ε
  • F 1,2

I

  • ε
  • | Cα

8 F 1,2

O

  • ε
  • ε
  • F 1,1

I

  • ε
  • ε
  • |

ε

  • F 2,1

I

  • ε
  • ε
  • | Cα

9 F 2,2

O

  • ε
  • ε
  • F 1,1

I

  • ε
  • ε
  • | Cα

10 Cα →

  • =1
  • Cα |
  • =1
  • 11

Grammatical modeling – p. 38/62

slide-79
SLIDE 79

MTSAG for α-channels

Multi-tape S-attribute grammar for α-channels

To each production rule, associate a functions which allows a recursive computation of the energy.

Grammatical modeling – p. 39/62

slide-80
SLIDE 80

MTSAG for α-channels

F α

ap =

                                                                        

fenergy

F 1,1 I → ε

  • ε
  • F 1,1

O

  • ε
  • ε

(uvxyz)

= x.energy + (u.hp+v.hp)·(y.hp+z.hp)

2

fenergy

F 1,1 I → ε

  • F 2,1

O

  • ε
  • ε

(uxyz)

= x.energy + (u.hp)·(y hp+z.hp)

√ 2

fenergy

F 1,1 I → ε

  • ε
  • F 1,2

O

  • ε

(uvxy)

= x.energy + (u.hp+v.hp)·(y.hp)

√ 2

fenergy

F 1,1 I → ε

  • F 2,2

O

  • ε

(uxy)

= x.energy + u hp · y.hp fenergy

F 1,1 I →Cα (x)

= x.energy fenergy

F 2,1 I → ε

  • ε
  • F 1,1

O

  • ε
  • ε

(uvxyz)

= x.energy + (u.hp+v.hp)·(y.hp+z. hp)

2

fenergy

F 2,1 I → ε

  • ε
  • F 1,2

O

  • ε

(uvxy)

= x.energy + (u.hp+v.hp)·(y.hp)

√ 2

fenergy

F 2,1 I →Cα (x)

= x.energy fenergy

F 1,2 I → ε

  • ε
  • F 1,1

O

  • ε
  • ε

(uvxyz)

= x.energy + (u.hp+v.hp)·(y.hp+z. hp)

2

fenergy

F 1,2 I → ε

  • F 2,1

O

  • ε
  • ε

(uxyz)

= x.energy + (u.hp)·(y hp+z.hp)

√ 2

fenergy

F 1,2 I →Cα (x)

= x.energy fenergy

F 2,2 I → ε

  • ε
  • F 1,1

O

  • ε
  • ε

(uvxyz)

= x.energy + (u.hp+v.hp)·(y.hp+z. hp)

2

fenergy

F 2,2 I →Cα (x)

= x.energy fenergy

F 1,1 O → ε

  • ε
  • F 1,1

I

  • ε
  • ε

(uvxyz)

= x.energy fenergy

F 1,1 O → ε

  • F 2,1

I

  • ε
  • ε

(uxyz)

= x.energy fenergy

F 1,1 O → ε

  • ε
  • F 1,2

I

  • ε

(uvxy)

= x.energy fenergy

F 1,1 O → ε

  • F 2,2

I

  • ε

(uxy)

= x.energy fenergy

F 1,1 O →Cα (x)

= x.energy fenergy

F 2,1 O → ε

  • ε
  • F 1,1

I

  • ε
  • ε

(uvxyz)

= x.energy fenergy

F 2,1 O → ε

  • ε
  • F 1,2

I

  • ε

(uvxy)

= x.energy fenergy

F 2,1 O →Cα (x)

= x.energy fenergy

F 1,2 O → ε

  • ε
  • F 1,1

I

  • ε
  • ε

(uvxyz)

= x.energy fenergy

F 1,2 O → ε

  • F 2,1

I

  • ε
  • ε

(uxyz)

= x.energy fenergy

F 1,2 O →Cα (x)

= x.energy fenergy

F 2,2 O → ε

  • ε
  • F 1,1

I

  • ε
  • ε

(uvxyz)

= x.energy fenergy

F 2,2 O →Cα (x)

= x.energy fenergy

Cα→

  • =1

(xy) = x.hp · Kmilieu + y.energy fenergy

Cα→

  • =1

(x)

= x.hp · Kmilieu

Grammatical modeling – p. 39/62

slide-81
SLIDE 81

MTSAG for α-channels

An example !

Grammatical modeling – p. 40/62

slide-82
SLIDE 82

MTSAG for α-channels

Periplasme Cytoplasme

A V A L P E D L Q I D L L I L A D M R H L G V G C

Grammatical modeling – p. 41/62

slide-83
SLIDE 83

MTSAG for α-channels

Sα, 115.64

A

ε

  • 0.22

Sα, 115.64

V

ε

  • 4.67

Sα, 115.64

L

ε

  • 5.66

Sα, 115.64

L

ε

  • 5.66

Sα, 115.64

I

ε

  • 4.67

Sα, 115.64

G

ε

  • 0.00

Sα, 115.64

A

ε

  • 0.22

Canalcyt, 77.54 F 1,1

O,cyt, 41.77

ε

A

  • 0.22

ε

V

  • 4.67

F 1,1

I,cyt, 41.77

ε

L

  • 5.66

ε

L

  • 5.66

F 1,2

O,cyt, 9.19

ε

I

  • 4.77

F 2,1

I,cyt, 9.19

ε

G

  • 0.00

ε

A

  • 0.22

F 1,1

O,cyt, 9.78

cyt, 9.78

D

D

  • −3.08

cyt, 3.62

E

E

  • −1.81

P

ε

  • −2.23

D

ε

  • −3.08

L

ε

  • 5.66

H

ε

  • 0.46

C

ε

  • 4.07

L

ε

  • 5.66

R

ε

  • 1.42

Canalper, 35.31 F 1,1

O,per, 35.31

ε

P

  • −2.23

ε

D

  • −3.08

F 1,1

I,per, 35.31

ε

L

  • 5.66

F 2,1

O,per, 23.99

ε

H

  • 0.46

ε

C

  • 4.07

F 1,1

I,per, 23.99

ε

L

  • 5.66

ε

R

  • 1.42

F 1,2

O,per, 2.81

per, 2.81

G

G

  • 0.00

per, 2.81

Q

Q

  • −2.81

M

ε

  • 4.23

I

ε

  • 4.77

V

ε

  • 4.67

L

ε

  • 5.66

G

ε

  • 0.00

A

ε

  • 0.00

L

ε

  • 5.66

ε

M

  • 4.23

ε

I

  • 4.77

ε

V

  • 4.67

ε

L

  • 5.66

ε

G

  • 0.00

ε

A

  • 0.22

ε

L

  • 5.66

Grammatical modeling – p. 41/62

slide-84
SLIDE 84

MTSAG for β-channels

✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✁ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✂ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ✄ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ☎ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✆ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✝ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✞ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✟ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✠ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ✡ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☛ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ☞ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✌ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✍ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✎ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✏ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✑ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✒ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓

Cytoplasme Periplasme

V C L V I L H L K Q A I F M W C W L V L G D E P A

Grammatical modeling – p. 42/62

slide-85
SLIDE 85

MTSAG for β-channels

Sβ, 71.92 Sβ

O, 71.92

C

ε

  • 4.07

I , 70.75

A

ε

  • 0.22

O, 70.23

V

ε

  • 4.67

I , 66.34

L

ε

  • 5.66

T β

seq,cyt, 61.63

T β

cyt, 24.50

F O

cyt, 24.50

ε

C

  • 4.07

F I

cyt, 20.40

ε

A

  • 0.22

F O

cyt, 20.34

ε

V

  • 4.67

F I

cyt, 15.74

ε

L

  • 5.66

F O

cyt, 11.71

F I+

cyt, 10.54

cyt, 10.54

K

K

  • −3.04

cyt, 4.46

P

P

  • −2.23

V

ε

  • 4.67

I

ε

  • 4.77

L

ε

  • 5.66

H

ε

  • 0.46

L

ε

  • 5.66

T β

seq,per, 37.13

T β

per, 16.01

F O

per, 16.01

ε

V

  • 4.67

F I

per, 12.54

ε

I

  • 4.77

F O

per, 9.10

ε

L

  • 5.66

F I

per, 7.53

ε

H

  • 0.46

F O

per, 6.99

ε

L

  • 5.66

F I

per, 2.59

per, 2.59

Q

Q

  • −2.81

per, −0.22

A

A

  • 0.22

F

ε

  • 4.44

M

ε

  • 4.23

W

ε

  • 1.04

I

ε

  • 4.77

C

ε

  • 4.07

T β

seq,cyt, 21.12

T β

cyt, 21.12

F O

cyt, 21.12

ε

F

  • 4.44

F I

cyt, 19.86

ε

M

  • 4.23

F O

cyt, 16.25

ε

W

  • 1.04

F I

cyt, 14.93

ε

I

  • 4.77

F O

cyt, 10.9

ε

C

  • 4.07

F I−

cyt, 9.78

per, 9.78

E

E

  • −1.81

per, 6.16

D

D

  • −3.08

per, 0.00

G

G

  • 0.00

L

ε

  • 5.66

V

ε

  • 4.67

L

ε

  • 5.66

W

ε

  • 1.04

ε

L

  • 5.66

ε

V

  • 4.67

ε

L

  • 5.66

ε

W

  • 1.04

Grammatical modeling – p. 42/62

slide-86
SLIDE 86

MTSAG for TM channels

What has not been said :

TM-channel closure, TM α-helix selection, turn selection (between secondary structures), constraints on the overlapping of the motifs.

Grammatical modeling – p. 43/62

slide-87
SLIDE 87

Performance evaluation

Performance evaluation

How to realize a structure prediction ? How to evaluate a prediction ? Results.

Performance evaluation – p. 44/62

slide-88
SLIDE 88

How to realize a structure prediction ?

syntax analysis (GCP algorithm), implementation using mtsag2c (F . Lefebvre), software tmmtsag... and now ASTRiD (web interface).

Performance evaluation – p. 45/62

slide-89
SLIDE 89

How to realize a structure prediction ?

Example of an α-channel : Bacteriorhodopsin

QAQITGRPEWIWLALGTALMGLGTLYFLVKGMGVSDPDAKKFYAITTLVPAIAFTMYLSMLLGYGLTMVPFGGEQNPIYWARYADWLFTTPLLLLDLALL .......TTHHHHHHHHHHHTTHHHHHHHHSS..S.HHHHHHHHHHHHTHHHHHHHHHHHHTT.....SSS.SSS....STTHHHHTTTHHHHTTTTSTT ............MMMMMMMMMMMMMMMMMMMMMMiiiiiiiPPMPPMPPMMPPMMPPMMPPMMPPMMPPooooooooPPMPPMPPMPPMMPPMPPMPPMP ............PMMPMMPMMPMMPMMPMMPMMPiiiiiiiPMMPMMPPMMPPMMPPMMPPMMPPMMPPooooooooPPMMPPMMPPMMPPMMPMMPMMP VDADQGTILALVGADGIMIGTGLVGALTKVYSYRFVWWAISTAAMLYILYVLFFGFTSKAESMRPEVASTFKVLRNVTVVLWSAYPVVWLIGSEGAGIVP TT..HHHHHHHHHHHHHHHHHHHHHHS..SSS.HHHHHHHHHHHHHHHHHHHTTTTTTT..TT.SHHHHTTHHHHHHHHHHHHHHHHHHTTTTSSSSSS. PiiiiiiPPMPPMPPMPPMPPMPPMMPoooPPMMPPMMPPMMPPMMPPMMPPMMPPiiiiiiPPMMPMMPPMPPMMPMMPPMMPPMPPMPPooooooPPM PiiiiiiPPMPPMPPMPPMPPMPPMMPoooPMMPPMPPMPPMPPMPPMPPMPPMMPiiiiiiPPMMPPMMPMMPMMPMMPPMMPPMPPMPPooooooMMM LNIETLLFMVLDVSAKVGFGLILLRSRAIFGEAEAPEPSAGDGAAATS SHHHHHHHHHHHHHHTHHHHTTTT........................ PPMPPMPPMPPMPPMMPMMPPMPP........................ MMMMMMMMMMMMMMMMMMMMMMMM........................ pseudo folding energy : 1583.92

Performance evaluation – p. 46/62

slide-90
SLIDE 90

How to realize a structure prediction ?

PPMPPMPPMPPMPPMPPMMPoooPMMPPMPPMPPMPPMPPMPPMPPMMPiiiiiiPPMMPPMMPMMPMMPMMPPMMPPMPPMPP PPMPPMPPMPPMPPMPPMMPoooPPMMPPMMPPMMPPMMPPMMPPMMPPiiiiiiPPMMPMMPPMPPMMPMMPPMMPPMPPMPP helice k−1 helice k helice k+1

tape 1 tape 2

Performance evaluation – p. 46/62

slide-91
SLIDE 91

How to realize a structure prediction ?

Example of a β-channel : Porin

MAPKDNTWYTGAKLGWSQYHDTGLINNNGPTHENKLGAGAFGGYQVNPYVGFEMGYDWLGRMPYKGSVENGAYKAQGVQLTAKLGYPITDDLDIYTRLGG ....TT.EEEEEEEEEES.S.....SS.......EEEEEEEEEEE.BTTEEEEEEEEEEEE.....SS....EEEEEEEEEEEEEEESSSSEEEEEEEEE ...............EEEEEEEEEEooooooooooCBCBCBCBCiiiiiiBCBCBCBCBCBCooooooooooooooBCBCBCBCBiiiiiiiiBCBCBCB ...............CBCBCBCBCBooooooooooBCBCBCBCBiiiiiiBCBCBCBCBCBCooooooooooooooBCBCBCBCBiiiiiiiiCBCBCBC MVWRADTYSNVYGKNHDTGVSPVFAGGVEYAITPEIATRLEYQWTNNIGDAHTIGTRPDNGMLSLGVSYRFG EEEEEEE..SSS..EEEEEEEEEEEEEEEEESSSSEEEEEEEEEE......SS........EEEEEEEEEE. CBCBCooooooooooooooCBCBCBCBCiiiCBCBCBCBCBCoooooooooooooooooooBCBCBCBCBC. BCBCBooooooooooooooCBCBCBCBCiiiCBCBCBCBCBCoooooooooooooooooooEEEEEEEEEE. pseudo folding energy : 402.15

Performance evaluation – p. 46/62

slide-92
SLIDE 92

How to evaluate a prediction ?

  • bserved : ......HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHH........

predition : ..HHHHHHHHHHHHHHH.........HHHHHHHHHHH.............HHHHHHHHHHHHHHH...

Definition A secondary structure is said to be predicted, if it intersects one and only one observed secondary structure. Definition A structure is correctly predicted if all its secondary structures are predicted, almost predicted if the non-predicted secondary structures do not intersect any observed secondary structures, and non-predicted otherwise.

Performance evaluation – p. 47/62

slide-93
SLIDE 93

How to evaluate a prediction ?

........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH.........HHHHHHHHHHHHH...............HHHHHHHHHHHHHHH........

Performance evaluation – p. 48/62

slide-94
SLIDE 94

How to evaluate a prediction ?

C

  • r

r e c t

........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH.........HHHHHHHHHHHHH...............HHHHHHHHHHHHHHH........

Performance evaluation – p. 48/62

slide-95
SLIDE 95

How to evaluate a prediction ?

C

  • r

r e c t

........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH.........HHHHHHHHHHHHH...............HHHHHHHHHHHHHHH........ ........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH..............HHHHHHHHHHHHHHHHHH............................

Performance evaluation – p. 48/62

slide-96
SLIDE 96

How to evaluate a prediction ?

C

  • r

r e c t A l m

  • s

t

........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH.........HHHHHHHHHHHHH...............HHHHHHHHHHHHHHH........ ........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH..............HHHHHHHHHHHHHHHHHH............................

Performance evaluation – p. 48/62

slide-97
SLIDE 97

How to evaluate a prediction ?

C

  • r

r e c t A l m

  • s

t

........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH.........HHHHHHHHHHHHH...............HHHHHHHHHHHHHHH........ ........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH..............HHHHHHHHHHHHHHHHHH............................ ........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH.................HHHHHHHHHHHHHHHHHHHHHH....HHHHHHHHHHHHHHH..

Performance evaluation – p. 48/62

slide-98
SLIDE 98

How to evaluate a prediction ?

C

  • r

r e c t A l m

  • s

t N

  • ........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH.............

..HHHHHHHHHHHHHHHHH.........HHHHHHHHHHHHH...............HHHHHHHHHHHHHHH........ ........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH..............HHHHHHHHHHHHHHHHHH............................ ........HHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHHH...HHHHHHHHHHHHHHHHH............. ..HHHHHHHHHHHHHHHHH.................HHHHHHHHHHHHHHHHHHHHHH....HHHHHHHHHHHHHHH..

Performance evaluation – p. 48/62

slide-99
SLIDE 99

How to evaluate a prediction ?

Estimator for the secondary structure element prediction

Qok = 100 · number of correctly predicted structures number of proteins Q%obs

stm

= 100 · number of TM segments correctly predited number of TM segment observed Q%pred

stm

= 100 · number of TM segments correctly predited number of TM segment predicted

Performance evaluation – p. 49/62

slide-100
SLIDE 100

How to evaluate a prediction ?

Estimator for the secondary structure assignment prediction

Q2 = 100 · number of correctly predicted residus number of residus Q%obs

2T

= 100 · number of correctly predicted residus in TM segment number of residus observed in TM segments Q%pred

2T

= 100 · number of correctly predicted residus in TM segment number of residus predicted in TM segments Q%obs

2N

= 100 · number of correctly predicted residus in non-TM segment number of residus observed in non-TM segments Q%pred

2N

= 100 · number of correctly predicted residus in non-TM segment number of residus predicted in non-TM segments

Performance evaluation – p. 50/62

slide-101
SLIDE 101

Results

Procedure

28 α-TM proteins known at high resolution level, 82 α-TM proteins known at low resolution level, 14 β-TM proteins known at high resolution level, 567 globular proteins, computation of sub-optimals structures, comparison with 8 other software.

Performance evaluation – p. 51/62

slide-102
SLIDE 102

Results

α-TM proteins known at high resolution level

topology helices 2-states TM residus non-TM residus Method Qok Q%obs

stm

Q%pred

stm

Q2 Q%obs

2T

Q%pred

2T

Q%obs

2N

Q%pred

2N

tmmtsag-basic 75.00(92.86) 97.18 93.88 78.24 87.56 78.77 64.04 77.16 tmmtsag-opt 92.86(100.00) 99.30 98.60 80.06 89.17 80.07 66.17 80.04 hmmtop2 71.43(100.00) 97.18 96.50 79.50 71.84 92.55 91.18 68.00 memsat 60.00(100.00) 94.00 97.92 77.43 67.63 94.34 93.39 63.91 phd-psihtm 71.43(96.43) 88.73 96.92 76.29 68.76 89.55 87.77 64.83 pred-tmr 53.57(100.00) 88.73 100.00 74.41 59.12 97.52 97.71 61.07 sosui 82.14(100.00) 97.18 99.28 80.70 72.71 93.95 92.87 69.10 tmhmm1 71.43(100.00) 96.48 97.16 79.80 72.76 92.13 90.52 68.56 toppred2 71.43(100.00) 95.07 94.41 75.69 66.31 90.98 89.98 63.67 Performance evaluation – p. 52/62

slide-103
SLIDE 103

Results

α-TM proteins known at low resolution level

topology helices 2-states TM residus non-TM residus Method Qok Q%obs

stm

Q%pred

stm

Q2 Q%obs

2T

Q%pred

2T

Q%obs

2N

Q%pred

2N

tmmtsag-basic 37.80(73.17) 87.11 81.68 69.30 87.06 60.31 55.50 84.67 tmmtsag-opt 60.98(95.12) 95.70 91.42 75.25 90.42 65.79 63.47 89.51 hmmtop2 60.98(86.59) 87.11 93.31 84.39 81.69 82.44 86.48 85.88 memsat 54.88(92.68) 91.02 93.20 85.26 81.40 84.80 88.35 85.60 phd-psihtm 24.36(43.59) 60.04 72.02 83.99 91.08 76.60 78.51 91.93 pred-tmr 50.00(96.34) 88.09 96.57 85.19 75.86 88.63 92.44 83.14 sosui 48.78(90.24) 86.33 94.85 82.36 79.17 80.21 84.83 83.98 tmhmm1 69.51(89.02) 90.23 95.45 85.32 83.02 83.34 87.11 86.85 toppred2 53.66(86.59) 83.59 95.75 83.46 74.48 85.81 90.43 82.02 Performance evaluation – p. 53/62

slide-104
SLIDE 104

Results

β-TM proteins known at high resolution level

topology strands 2-states TM residus non-TM residus Method Qok Q%obs

stm

Q%pred

stm

Q2 Q%obs

2T

Q%pred

2T

Q%obs

2N

Q%pred

2N

total tmmtsag-basic 7.14(78.57) 83.14 66.82 64.87 72.71 69.99 53.07 56.37 tmmtsag-opt 21.43(92.86) 90.70 82.98 66.80 74.03 71.66 55.93 58.85 tmb-hmm 64.29(100.00) 97.09 97.09 84.04 85.75 87.45 81.47 79.15 small proteins tmmtsag-basic 50.00(75.00) 90.62 80.56 70.23 74.30 79.50 62.21 55.10 tmmtsag-opt 50.00(100.00) 93.75 93.75 76.12 78.97 84.08 70.51 62.96 tmb-hmm 75.00(100.00) 96.88 96.88 82.33 83.64 89.05 79.72 71.19 Performance evaluation – p. 54/62

slide-105
SLIDE 105

Results

500 1000 1500 2000 2500 3000 3500 4000 100 200 300 400 500 600 pseudo-energie de repliement longueur des sequences hires-alpha lowres-alpha glob 2.7 × x

Performance evaluation – p. 55/62

slide-106
SLIDE 106

Results

500 1000 1500 2000 2500 3000 3500 4000 100 200 300 400 500 600 pseudo-energie de repliement longueur des sequences hires-beta glob 2.7 × x

Performance evaluation – p. 56/62

slide-107
SLIDE 107

Results

500 1000 1500 2000 2500 3000 3500 4000 100 200 300 400 500 600 pseudo-energie de repliement longueur des sequences hires-alpha lowres-alpha hires-beta glob 2.7 × x

Performance evaluation – p. 57/62

slide-108
SLIDE 108

Results

false positives (%) Method false negatives (%) ∆tm,α

hires

∆tm,α

lowres

∆tm,β

hires

∆tm

α+β

tmmtsag-basic 14.8 8.5 7.1 6.2 hmmtop2 6 1

  • phd-psihtm

2 3 8

  • pred-tmr

4 8 1

  • sosui

1 8 4

  • tmhmm1

1 8 4

  • toppred2

10 8 11

  • tmb-hmm

10

  • Performance evaluation – p. 58/62
slide-109
SLIDE 109

Conclusion

What has been done : tmmtsag is the first software able to : use efficiently and without restrictions, long range interactions, unify α-channel and β-channel in the same model, discriminate the 3 categories α, β and globular. Advantages : simple, versatile and efficient, no learning method used (more able to detect new structures, with lack of experimental data’s).

Conclusion – p. 59/62

slide-110
SLIDE 110

Conclusion

What has to be done : refining the physical approximate model (structure and energy), integrating existing methods, modeling the quaternary structure, extension to globular proteins.

Conclusion – p. 60/62

slide-111
SLIDE 111

Conclusion

What we are doing : model refinement (joint work with T. Simonson), study of single point mutations in human rhodopsin (joint work with P . Clote), reconstructing the tertiary structure from contact predictions, screening of a complete genome, web interface : ASTRiD http ://www.lix.polytechnique.fr/Labo/Jerome.Waldispuhl/astrid/.

Conclusion – p. 61/62

slide-112
SLIDE 112

References

This work :

  • J. Waldispühl and J.-M. Steyaert,

Modeling and Predicting All-α Transmembrane Proteins Including Helix-helix Pairing, to appear in Theoretical Computer Science, special issue on pattern discovery in the post genom, 26 pages, 2005. available online : http ://www.elsevier.com/locate/tcs/ Multi-tape S-attributed grammars : F . Lefebvre, A Grammar-Based Unification of Several Alignment and Folding Algorithms, Proceedings of the Fourth International Conference on Intelligent Systems for Molecular Biology, pp 143-154, 1996. Slides : These slides have been realized with the Youpla L

A

T EXpackage, provided by

  • E. Thome. Download it, at : http ://www.loria.fr/∼thome/

Conclusion – p. 62/62