Overview of the Evasion Mechanisms Used by Bacteria
Michael M. Frank
from: Microbial Subversion of Immunity: Current Topics (Edited by: Peter J. Lachmann and M.B.A. Oldstone). Caister Academic Press, U.K. (2006)
Abstract
This chapter reviews some aspects of molecular mimicry used in evasion strategies of bacteria. For long term survival a bacterium must occupy a niche where it can survive, reproduce and spread. Pathogenic bacteria in invading man must deal with a wide assortment of innate and adaptive host defense responses and have themselves evolved a wide variety of bacterial protective mechanisms. In many cases this involves the use of the host's cellular or biochemical pathways to subvert the host attack. For example, a mammalian host has evolved sophisticated mechanisms to separate self from non-self so that attack on host structures by innate and adaptive immune responses with resultant tissue damage is minimized. Some bacteria have evolved mechanisms to disguise themselves as self, thereby thwarting the host defense process. In similar ways bacteria use host structures for invasion of cells and tissues and intracellular survival. Analysis of these mechanisms has often led to the finding of convergent evolution, the evolution of bacterial elements that have similar function to host elements but unique structure. In some cases there is actual incorporation of host genes by horizontal transfer. There is almost no aspect of the host defense process that some group of organisms has not subverted for pathogenic use read more ...
