小柯机器人

英国东英吉利大学Thomas A. Clarke和David J. Richardson团队合作取得一项新突破。他们解析了生物绝缘跨膜分子线的晶体结构。相关论文于2020年4月13日发表于《细胞》杂志上。

他们报告了跨膜蛋白复合物MtrAB的原子结构，该结构是已知在系统发生和代谢多样的微生物的内部和外部环境之间传递电子的蛋白质家族的代表。该结构显示为具有10个血红素细胞色素MtrA的天然绝缘生物分子丝，其通过嵌入由MtrB形成的26股β桶中与膜脂质环境绝缘。MtrAB与细胞外10-血红素细胞色素MtrC形成紧密连接，后者在大面积表面上呈现血红素，可与细胞外氧化还原伴侣（包括过渡金属和电极）进行电子交流。

据悉，人们认识到越来越多的细菌可以通过其细胞膜传导电子，但是支持该过程的机制的分子细节仍然未知。

附：英文原文

Title: The Crystal Structure of a Biological Insulated Transmembrane Molecular Wire

Author: Marcus J. Edwards, Gaye F. White, Julea N. Butt, David J. Richardson, Thomas A. Clarke

Issue&Volume: 2020-04-13

Abstract: A growing number of bacteria are recognized to conduct electrons across their cell envelope, and yet molecular details of the mechanisms supporting this process remain unknown. Here, we report the atomic structure of an outer membrane spanning protein complex, MtrAB, that is representative of a protein family known to transport electrons between the interior and exterior environments of phylogenetically and metabolically diverse microorganisms. The structure is revealed as a naturally insulated biomolecular wire possessing a 10-heme cytochrome, MtrA, insulated from the membrane lipidic environment by embedding within a 26 strand β-barrel formed by MtrB. MtrAB forms an intimate connection with an extracellular 10-heme cytochrome, MtrC, which presents its hemes across a large surface area for electrical contact with extracellular redox partners, including transition metals and electrodes.

DOI: 10.1016/j.cell.2020.03.032

Source: https://www.cell.com/cell/fulltext/S0092-8674(20)30325-1