1 / 6

Overview of Key Enteric and Gram-Negative Bacteria: Pathogens, Virulence, and Implications

This article provides insights into significant enteric and Gram-negative bacteria, focusing on Klebsiella pneumoniae, Serratia marcescens, Proteus mirabilis, Campylobacter jejuni, and Helicobacter pylori. We discuss their pathogenic roles in nosocomial pneumonia and urinary tract infections, highlighting their virulence factors such as urease production, hydrophobic surfaces, and swarming mobility. These organisms pose serious health risks, particularly to immunocompromised individuals. Understanding their characteristics and behaviors is essential for effective treatment and infection control.

kalli
Télécharger la présentation

Overview of Key Enteric and Gram-Negative Bacteria: Pathogens, Virulence, and Implications

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Misc. Enterics and Gram- bacteria

  2. Klebsiella K. pneumoniaeis most common pathogen Pneumonia (nosocomial) or UTI (makes urease) Often associated with patient intubation Uses type 1 and type 3 (MRK) fimbriae Environmental organism Associated with plant roots, fixes nitrogen

  3. Serratia • S. marcescensis most common human pathogen • Opportunistic pathogen • Death knell of nosocomial pneumonia • Produces proteases that degrade host tissue • Hydrophobic cell surface adheres to medical plastics • Causes corneal ulcers in contact wearers • Often produces pink/orange pigment called prodigin • Type 1 and type 3 fimbriae probably evolved from common Serratiafimbriae

  4. Proteus • P. mirabilis is most common pathogen • Primarily urinary tract infections • Proteus swarms-highly mobile • If you inoculate small point on agar plate proteus will swim out to form a large ring • Very strong urease producer-renal calculi

  5. Campylobacter Gram - bacterium grows at 42°C in High CO2, low oxygen C. jejuniis most common human pathogen-gastroenteritis, bloody diarrhea can last for 1 week Causes tissue damage in jejunum Virulence factors include LPS, adhesins and flagella catalase and oxidase Can spread, but is self-limiting C. fetus expresses S protein that prevents complement activity and phagocytosis Disseminates to blood and other systems readily Immunocompromised patients are most affected

  6. Helicobacter Gram - spiral -motile by spiral motility-humans are reservoir H. pylori is the most significant-causes gastric ulcers Acquired throughout life-more frequent in adults than children Urease is very important-allows localized pH change Penetrates mucosal cells into epithelium Tissue damage is caused by LPS, urease products, and a cytotoxin that damages epithelium Highly successful treatment with antibiotics

More Related