Zonnula occludens toxin: increases small intestinal permeability
Neuraminidase: modifies cell surface to increase GM1 – better binding
How does Vibrio cholerae acquire virulence?
Bacteriophage CTX binds to toxin-co-regulated pilus (tcp) and enters bacterium to become integrated into bacterial genome
These are the following genes transferred by the bacteriophage
ctxA and ctxB: cholera toxin subunits
ace: accessory cholera enterotoxin gene
zot: Zonnula occludens toxin gene
These are coordinated by ToxR regulator
How does cholera toxin work? What toxin is it similar to?
It is similar to the LT of E. Coli
Five B subunits bind GM1
A subunit enters cell and activates adenylyl cyclase
ATP -> cAMP resulting in hypersecretion of electrolytes
What virulence factor is associated with Vibrio parahaemolyticus?
Thermostable direct hemolysin (Kanagawa hemolysin) what it does is increase intracellular calcium which induces chloride secretion in epithelial cells, it also produces beta hemolysis on human blood agar
What virulence factors are associated with Vibrio vulnificus?
Antiphagocytic polysaccharide capsule
What are the sources of infection and disease caused by vibrio cholerae, parahaemolyticus, and vulnificus?
What treatment is there for Vibrio Cholera, parahaemolyticus, and vulnificus?
Vibrio cholera: first fluids, then doxycycline or tetracycline for adults, furazolidone for pregnant women, and trimethoprim-sulfamethoxazole for children *O139 is resistant to furazolidone and sulfa-trimethoprim*
Vibrio parahaemolyticus: fluids; antibiotics in extreme cases
Vibrio vulnificus: minocycline plus fluoroquinolone or cefotaxime
Describe the diarrhea associated with Campylobacter
Greenish watery, foul smelling
May be followed by bloody diarrhea
Severe abdominal pain and fever are associated
What organism infection is associated with Guillain-Barre syndrome?
Specifically serotype O:19
How do you grow campylobacter?
Have to use Campylobacter selective agar
Very little air/oxygen
How do you treat Campylobacter infections?
Septicemia or severe GI: Erythromycin or azithromycin, also can use tetracyclines or fluoroquinolones