5 terms

Microbiology Pathogenic Bacteria Lecture

Notes from Microbiology Lecture on Gram Positive Cocci, Gram Positive Rods, Gram Negative Cocci, Facultative Anaerobic Gram Negative Rods, Pathogenic Gram Negative Aerobic Rods, and other Gram Negatives
Describe the Staphylococcus Genus
Gram Positive Cocci in Clusters, Facultative Anaerobe, Catalase Positive, Lipase Positive, Halophile
What differentiates Staphylococcus from Streptococcus?
Staphylococcus's cocci are in clusters and catalase positive; whereas streptococcus gram positive cocci are in pairs or chains, facultative anaerobe with peroxidase, and catalase negative.
S. epidermidis
Opportunist, ubiquitous on skin, primarily infectious in immune compromised patient (Example: HIV) - Main normal flora of skin
S. aureus
Main pathogen, MANY Virulence Factors
Virulence Factors of S. aureus
1. Coagulase Positive (Hiding in the clot), Kinase, Hyaluronidase (hyaluronic acid - invades deeper), Beta hemolytic - lysis cells; Eats them Up!
2. Protein A - Binds stem of igG preventing opsonizations and complement
3. Slime Layer - Inhibits phagocytes, allows attachment to artificial surfaces (catheters, shunts, heart valves, artificial joints - loves plastic)
4. Beta lactamase - Brakes beta lactam ring of penicillin = resistant to penicillin and other Antibiotics, 90% of strains are resistant