Yersinia pestis B Clark F 2013 Modified by

Yersinia pestis B. Clark F 2013 Modified by DYH • Bacteria responsible for the Black Death, which killed over 1/3 of European population from 1347 -1353 • Gram negative, rod shaped coccobacillus • Unique morphology between cocci and bacilli • Obligate intracellular pathogen • Facultative anaerobe http: //en. wikipedia. org/wiki/Yersinia_pestis • Primary carriers are the Oriental rat flea and infected rodents • Produce antiphagocytic slime layer in its path • Genome size of strain CO 92 is 4. 65 Mbp and strain KIM is 4. 6 Mbp • 4, 198 total ORFs http: //www. rkm. com. au/bacteria/Yersinia-pestis. html

Yersinia pestis B. Clark F 2013 Modified by DYH • Can produce loose capsule in some cases • Lacks O-side chain due to disrupted Oanitgen gene cluster • Called a “rough mutant” • Infection takes three main forms: pneumonic, septicemic, & bubonic plagues • All pathogenic species contain p. CD 1 virulence plasmid • Uses a Type 3 Secretion System to inject bacterial proteins into host immune cells • LPS chains mediate antibody resistance • Expression of yad. BC gene is similar to adhesin function • Adherence and invasion of epithelial cells • Proliferates in lymph nodes where is can avoid destruction by immune system http: //www. ppdictionary. com/bacteria/gnbac/pestis. htm