The prokaryotic pleomorphic coccobacillus Yersinia pestis is part of the Yersinia genus which is part of the Enterobacteriacaie family (Cleri, et al., 1) and of the Enterobacteriales order, and of the Gammaproteobacteria class , and the phylum Proteobacteria, and the kingdom Bacteria. The Enterobactericaea family is also called enteric bacteria (Bauman, 631). Enteric bacteria are usually found in the intestinal microbiota of animals and humans (Bauman, 631). Some members of this family have obvious peritrichous flagella or capsules or only a loose silty layer (Bauman, 631). All members of the enteric bacterial family are Gram-negative, oxidase negative, and metabolize nitrate to nitrate (Bauman, 632). Yersinia species are Gram-negative, anaerobic, non-spore-forming bacilli or coccobacilli (Rollins, Rollins, & Ryan, 3). The genus Yersinia includes species that include Y. enterocolitica, Y. pseudotuberculosis, and Y. pestis (Bauman, 640). All three species are able to attach to human cells after the type III secretion system injects virulent proteins that trigger apoptosis into macrophages and neutrophils (Bauman, 640). Y. enterocolitica and Y. pseudotuberculosis are enteric pathogens that require consumption of food or water contaminated with animal fecal waste (Bauman, 640). Y pestis must use a flea as an infectious vector to transmit virulent proteins to humans (Bauman, 640). Unlike other Yersinia subspecies, Y. pestis is capsulated with a cell envelope at 33 degrees Celsius (Rollins, Rollins, & Ryan, 4). DNA studies of Y. pestis and Y. pseudotuberculosis have shown 90% similarity and 99.7 similarity in their ribosomal ribonucleic acid (RNA) 16s (Rollins, Rollins, & Ryan, 4). Y. pestis...... middle of the paper ...... odel and discovered another method for the transmission of Y. pestis were authentic in the research stating that biofilms were crucial for the maintenance of Y. pestis. Perhaps if biofilms were not necessary then it would be clearer why flea species that do not develop biofilm blocks are able to act as vectors of Y. pestis. The article was very informative about how fleas are able to contract Y. pestis and transmit it to humans. Reading the article I realized the importance of biofilms and that without the blockages that occur due to biofilms Y. pestis would not be able to survive. The article focused primarily on the transmission of the bacteria and did not include many basic details about the disease. I had to rely on my research to discover information about the bacterium itself and how and why it is so fatal to humans.