Cellular Structures and Pathogenicity
Jennifer L. Wethington
ITT Technical Institute
Unit 2 Assignment 1 “Bacterial illness is a result of complex interactions between bacteria and the host. During evolution, humans developed many ways to protect themselves against bacterial pathogens. On the other hand, bacteria have developed strategies to evade, subvert or circumvent these defenses” (Sousa, 2003) “One of the most important characteristics of bacterial pathogenicity is the various strategies developed by prokaryotic organisms to use host molecules for their own benefit” (Sousa, 2003). “To accomplish this, bacteria have evolved elaborate control mechanisms to turn genes on and off, varying the transcriptional activator or protein repressors of systems that act at the structural level of the genetic material” (Sousa, 2003).
“Without a doubt the most common and best studied of all prokaryotic motility structures is the bacterial flagellum. Composed of over 20 protein species with approximately another 30 proteins required for regulation and assembly, it is one of the most complex of all prokaryotic organelles” (Bardy, Ng, & Jarrell, 2003). “The bacterial flagellum is a rotary structure driven from a motor at the base, with the filament acting as a propeller. The flagellum consists of three major substructures: the filament, the hook and the basal body” (Bardy, Ng, & Jarrell, 2003).
“One of the unusual variations on bacterial flagellation is the presence in certain organisms of both a polar and a lateral flagellation system. In Escherichia coli, Proteus sp., Salmonella typhimurium and Serratia marcescens, it has been demonstrated that the flagella of swimming and swarming cells are the same, although their numbers are different” (Bardy, Ng, & Jarrell, 2003). “Other organisms assemble two different organelles. Best studied in the Vibrionaceae,