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

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

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

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

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