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128 SEcTioN ii Microbiology ` microbiology—basic bacteriology Microbiology ` microbiology—basic bacteriology

Catalase-positive Catalase degrades H 2 O 2 into H 2 O and bubbles of O 2 A before it can be converted to microbicidal
organisms products by the enzyme myeloperoxidase. People with chronic granulomatous disease (NADPH
oxidase deficiency) have recurrent infections with certain catalase ⊕ organisms.
A
Examples: Nocardia, Staphylococci, Serratia, Candida, Listeria, E coli, Burkholderia cepacia,
Pseudomonas, Aspergillus, Helicobacter pylori, Bordetella pertussis.

Pigment-producing Actinomyces israelii—yellow “sulfur” granules, Israel has yellow sand
bacteria which are composed of filaments of bacteria

S aureus—yellow pigment Aureus (Latin) = gold
P aeruginosa—blue-green pigment (pyocyanin Aerugula is green
and pyoverdin)
Serratia marcescens—red pigment Think red Sriracha hot sauce

In vivo biofilm- S epidermidis Catheter and prosthetic device infections
producing bacteria Viridans streptococci (S mutans, S sanguinis) Dental plaques, infective endocarditis
P aeruginosa Respiratory tree colonization in patients with
cystic fibrosis, ventilator-associated pneumonia
Contact lens–associated keratitis
Nontypeable (unencapsulated) H influenzae Otitis media

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