iccdB Intelligent Control of Cell Density in Bacteria Xiamen - PowerPoint PPT Presentation

iccdB — — Intelligent Control of Cell Density in Bacteria Xiamen University 2011

Our Team • 9 Undergraduates • 3 Advisors

Inspiration Pu’er Tea Fermentation

iccdB A bacteria population-control device — — Intelligent Control of Cell Density in Bacteria

Mechanism LuxR Producer LuxI Producer CcdB Producer

Mechanism an acyl-[acp] a holo-[acp] + s-adenosyl-L-methionine AHL s-methyl-5'-thioadenosine IPTG AHL LuxR LuxR LuxI CcdB lacZ α -ccdB lacl+pL luxI lacl+pL luxR lux pR

Mechanism IPTG AHL LuxR LuxI CcdB LuxR lacZ α -ccdB lacl+pL luxI lacl+pL luxR lux pR

Mechanism CcdB Gyrase

Mechanism CcdB- Gyrase Complex

Performance • Bacteria population control devices 24h 32h

Performance A series of bacteria population control devices based on RBSes Mutation of promoter lux pR Influence of iccdB on expression of downstream genes

Performance “Can we generate a series of devices that program bacteria population maintain at different cell densities? ”

Performance • Different RBSes Cell Growth Column Graph 20.00 Colony-Forming Units /mL -1 X10 -8 18.00 16.00 14.7 14.00 12.00 CcdB 10.00 6.92 8.00 6.00 4.45 4.00 2.53 1.68 2.00 lacZ α -ccdB lux pR 0.00 RBS 0.07 RBS 0.3 BL21 iccdB0.07 iccdB0.3 iccdB0.6 iccdB1.0 RBS 0.6 RBS 1.0 Devices

Modeling

Performance “What else? ”

Performance • Mutations of lux pR —— Expression efficiency IPTG AHL EGFP gfp luxI luxR lux pR

• Mutations of lux pR —— Expression efficiency ACCTGTAGG gfp lux pR ACCTGTAGG gfp lux pR ACCTGTAGG gfp lux pR

• Mutations of lux pR —— Expression efficiency AC TGTAGG T Promoters Strength Relative to lux pR-3 (BBa_K658006) gfp lux pR - 3 120.00 100.00 100.00 Efficiency /% ACCT TAGG C 80.00 56.54 60.00 40.00 lux pR - 5 gfp 11.89 20.00 6.02 0.00 lux pR-5 lux pR-3 lux pR lux pR-3/5 T C AC T TAGG Devices gfp

Performance • Mutations of lux pR —— iccdB-X Cell Growth Column Graph 3.5 Colony-Forming Units / mL -1 3 2.53 2.5 X10 -8 2 1.51 1.5 CcdB 1 EGFP 0.5 0 iccdB-3 iccdB0.6 Devices lacZ α -ccdB lux pR-3

Performance • Influence of iccdB on downstream genes Fluorescence of Different Devices 1800 1602.4 1600 1400 Fluorescence 1203.1 1200 1000 800 600 400 200 0 GFP iccdB-GFP iccdB0.6 lacl+pL gfp Devices

Future Plan Induced by IPTG ccdB luxI luxR coding

Summary Designed and characterized a series of bacteria population-control devices. Improved the strength of promoter lux pR by site- directed mutagenesis. Characterized the efficiency of promters lux pR and its 3 mutants. Designed and characterized the device iccdB-GFP to test the influence of iccdB on downstream genes.

Scientific Achievement

Human Practice Open lab day for kids Biosafety lecture

Open lab day for kids • 20 kids from Yan Wu primary school • Exhibition about microorganism • Lecture about synthetic biology • Basic experiment

Biosafety lecture Top questions 8% 3% 45% 18% 26% Genetically modified foods Majors Artificial microorganism Arts 8% Economics Bio-leakage from laboratory 25% Lingusitic 25% Threat of Human Genome Project on Chemistry Human rights 27% Management Others 10% Others 5%

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Acknowledgements Steve Jobs

Thank you