bacterial secretion and the role of diffusive and subdiffusive first passage processes细菌分泌和扩散的作用,subdiffusive首次通过流程.pdf

Bacterial Secretion and the Role of Diffusive and Subdiffusive First Passage Processes 1 1 1,2,3 Frank Marten , Krasimira Tsaneva-Atanasova , Luca Giuggioli * 1 Department of Engineering Mathematics, University of Bristol, Bristol, United Kingdom, 2 School of Biological Sciences, University of Bristol, Bristol, United Kingdom, 3 Bristol Centre for Complexity Sciences, University of Bristol, Bristol, United Kingdom Abstract By funneling protein effectors through needle complexes located on the cellular membrane, bacteria are able to infect host cells during type III secretion events. The spatio-temporal mechanisms through which these events occur are however not fully understood, due in part to the inherent challenges in tracking single molecules moving within an intracellular medium. As a result, theoretical predictions of secretion times are still lacking. Here we provide a model that quantifies, depending on the transport characteristics within bacterial cytoplasm, the amount of time for a protein effector to reach either of the available needle complexes. Using parameters from Shigella flexneri we are able to test the role that translocators might have to activate the needle complexes and offer semi-quantitative explanations of recent experimental observations. Citation: Marten F, Tsaneva-Atanasova K, Giuggioli L (2012) Bacterial Secretion and the Role of Diffusive and Subdiffusive First Passage Processes. PLoS ONE 7(8): e41421. doi:10.1371/journal.pone.0041421 ˇ Editor: Matjaz Perc, University of Maribor, Slovenia Received February 27, 2012; Accepted June 21, 2012; Published August 6, 2012 Copyright: 2012 Marten et al. This is an open-access article distributed under the terms of the Creative Commons A