Presented by: Zhaowei Jiang, Xiao Hui Zheng, Emilie Oakes, Wanyue Cui - - PowerPoint PPT Presentation

Presented by: Zhaowei Jiang, Xiao Hui Zheng, Emilie Oakes, Wanyue Cui

Background: Fluid Mosaic Membrane

The Fluid Mosaic Model of the Structure of Cell Membranes Author(s): S. J. Singer and Garth L. Nicolson Source: Science, New Series, Vol. 175, No. 4023 (Feb. 18, 1972), pp. 720-731

Background: The Bilayer Couple Hypothesis

The two halves of the closed membrane bilayer may respond differently to various perturbations while remaining coupled to one another.

Background: Erythrocyte

https://www.thoughtco.com/red-blood-cells-373487

Background: Tertiary and Quaternary Amines

http://www.ochempal.org/index.php/alphabetical/s-t/tertiary-amine/

Motivation & Goals

• Test bilayer couple hypothesis
• Use this hypothesis to explain the nonspecific noncovalent interaction of a

wide range of drugs on the human erythrocyte

Materials & Methods - Reagents

Hemolysis Protection Experiment

1.https://www.ars.usda.gov/northeast-area/docs/safety-health-and-environmental-training/centrifuge-operation/ 2.https://www.indiamart.com/proddetail/uv-vis-spectrophotometer-15379964597.html

Imaging

1.http://laboratorybiologicalmicroscope.wholesale.autoplansearch.com/c1563490-polarized-light-microscopy 2.https://www.jeol.co.jp/en/products/detail/JSM-7610F.html

Scanning Electron Microscopy

• 1. https://www.pinterest.com/pin/342344009146047159/?lp=true

Substance Critical temperature Critical pressure Water 373.95 °C 217.7 bar Acetone 235 °C 46 bar CO2 31.04°C 72.8 bar

Observation

Observation

Methochlormazine Quaternary amine Crenator Chlormazine Tertiary amine Cup-former

Observation

Conclusion

While these new experimental findings, therefore, provide strong additional support for the bilayer-couple mechanism of drug-erythrocyte interactions, they do not prove that each of the many individual elements in the proposal is correct. It would be desirable, for example, to obtain direct evidence about the proposed distributions of different drugs in the two halves of the erythrocyte bilayer by appropriate binding and exchange experiments with right-side-out and inside-out ghosts.

A bilayer couple model

Superiority

The proposed behavior of molecularly asymmetric membranes as bilayer couples may be significant to many phenomena in cell biology that involve shape changes in a cell

• r organelle, including cell

locomotion and ruffling, microvillus formation, cell-cell and cell-virus fusion, secretion, phagocytosis, and mitochondrial energization.

Scientists could do after this article

The possible generality of the proposed bilayer couple mechanism of drug-membrane interactions to other than erythrocyte membranes cannot be dwelt upon here. Whether, for example, an asymmetrical distribution of anionic phospholipids exists in other membranes is not known.

Discussion

The author put forward that membranes forming a closed surface, whose proteins and polar lipids are asymmetrically distributed in the two halves of the membrane bilayer, can act as bilayer couples. That is, the two halves can respond differently to a perturbation while remaining coupled to

• ne another.

Thank you

Questions?