staphylococci

• What family does *Staphylococcus* belong to?

  Micrococcaceae
• Who first observed staphylococci in pus specimens in 1878?

  Robert Koch
• What does the term “staphylococcus” mean in Greek?

  Bunch of grapes and berry
• Which scientist named the bacteria as *Staphylococcus*?

  Sir Alexander Ogston
• What is the characteristic color of colonies produced by *S. aureus*?

  Golden-yellow
• Which *Staphylococcus* species is pathogenic?

  *S. aureus*
• What test is used to differentiate coagulase-positive and coagulase-negative *Staphylococcus*?

  Coagulase test
• What is the natural habitat of *S. aureus*?

  Nostril and skin
• What is the optimal temperature for the growth of *S. aureus*?

  37°C
• On which agar does *S. aureus* produce yellow colonies due to mannitol fermentation?

  Mannitol salt agar (MSA)
• What type of hemolysis is exhibited by *S. aureus* on blood agar?

  Beta-hemolysis
• Which biochemical test is positive for *S. aureus* but negative for *Staphylococcus epidermidis*?

  Coagulase test
• What enzyme reduces nitrate to nitrite in *S. aureus*?

  Nitrate reductase
• What is the main virulence factor of *S. aureus* causing exfoliative diseases?

  Epidermal toxin
• Name a superficial skin infection caused by *S. aureus* common in children.

  Impetigo
• What is the deep-seated infection originating from folliculitis called?

  Furuncle/boil
• What is the term for an aggregation of infected furuncles?

  Carbuncle
• What condition is characterized by inflammation of the bone caused by *S. aureus*?

  Osteomyelitis
• What disease is also called Staphylococcal Scalded Skin Syndrome?

  Exfoliative disease
• Which strain of *S. aureus* is resistant to methicillin?

  MRSA
• Which diagnostic test determines the ability of *S. aureus* to ferment mannitol?

  Mannitol fermentation test
• What biochemical property of *S. aureus* allows it to hydrolyze gelatin?

  Gelatinase activity
• What kind of infection is commonly caused by *Staphylococcus saprophyticus* in women?

  Urinary tract infection (UTI)
• Name a clinical syndrome caused by toxins released by *S. aureus*.

  Toxic shock syndrome
• What type of leukocyte count is increased in infections caused by *S. aureus*?

  Neutrophils (>80%)
• What laboratory medium is selective for recovering *S. aureus* during food poisoning investigations?

  Mannitol salt agar
• What test result indicates a positive DNA-ase activity in *S. aureus*?

  DNA-ase test positive
• Which coagulase-negative *Staphylococcus* species commonly causes infections of native heart valves?

  *Staphylococcus epidermidis*
• What are the colony characteristics of *S. aureus* on MacConkey agar?

  Pink-colored colonies due to lactose fermentation
• What enzyme produced by *S. aureus* enables resistance to beta-lactam antibiotics?

  Beta-lactamase