Aerobic (+) bacteria

• 3 genera which are a non-spore-forming, nonbranching and catalase-positive bacilli:

  • Corynebacterium spp.
  • Rothia spp.
  • Listeria spp.
• Corynebacterium spp.


  A slightly curved, gram-positive rods with nonparallel sides and slightly wider ends, producing the described “club shaped” or “coryneform”
• Kleb Loeffler’s bacillus


  It is also known as Corynebacterium
• Club shaped rods


  The meaning of "coryne"
• Diphtheroid


  It is also known as Corynebacterium which means “diphtheria-like”
• Two divisions under the Corynebacterium species:

  • Nonlipophilic species
  • Lipophilic species
• Lipophilic


  What do we call a specie that is fastidious that grow slowly on standard culture media and must be incubated for 48 hours?
• Lipids

  It is included in the culture media for the lipophilic organism to grow and enhanced
• Diphtheria toxin


  A Heat-labile and major virulence factor produced by the strains of Corynebacterium diphtheriae
• Diphtheria toxin


  This toxin is produced by strains of Corynebacterium diphtheriae infected with a lysogenic β-phage, which carries the gene TOX.
• Fragment A


  A type of fragment of C. diptheriae that is responsible for cytotoxicity
• Fragment B

  A type of fragment of C. diptheriae that is responsible for binding onto the receptors of human cells and mediates entry of fragment A into

  the cytoplasm
• C. diptheriae have a protein of 62,000 daltons (Da)
• Two different forms of clinical infections in humans caused by Corynebacterium diphtheriae:

  • Respiratory diphtheria
  • Cutaneous diphtheria
• Respiratory diphtheria


  A type of clinical infection which is a sudden onset with exudative pharyngitis, sore throat, low-grade fever, and malaise; a thick pseudomembrane develops over the pharynx; in critically ill patients, cardiac and neurologic complications are most significant
• Mode of transmission for Respiratory diptheria disease:

  • Aerosol
  • nasopharyngeal route
  • nasal or oral discharges
• Exotoxin


  This can lead to the production of pseudomembrane in respiratory diphtheria
• Bull’s neck appearance 


  An appearance characterized by the patient which develops in the oropharynx which have respiratory diptheria
• Cutaneous diphtheria


  A papule that can develop on the skin, which progresses to a nonhealing ulcer and can develop systemic signs
• In terms of laboratory diagnosis, Corynebacterium is a highly pleomorphic gram-positive bacillus that is seen in microscope
• Corynebacteriym is a club-shaped swellings and beaded forms are common. It is often stain irregularly, especially when stained with methylene blue
• Corynebacterium is characterized as palisades (cells lie in parallel rows) or as individual cells lying at sharp angles to another in “V” and “L” formations
• Babés-Ernst Granules


  It is called the metachromatic areas of the cell of Corynebacterium
• Facultative anaerobe


  Aerotolerance of Corynebacterium
• 37° C


  The optimal growth temperature for Corynebacterium
• 15°C to 40°C

  A range of temperature which Corynebacterium occurs to multiply
• TRUE


  TRUE OR FALSE:

  Corynebacterium can grown on nutrient agar
• Loeffler serum or Pai agars


  Corynebacterium can grow in this agar that contains blood or serum
• very small


  The size of the zone of β-hemolysis of Corynebacterium
• Cystine-tellurite blood agar


  What does the acronym CTBA means? (this is a type of selective and differential medium)
• Potassium tellurite


  It is found in the CTBA which inhibits many non-coryneform bacteria
• Black or Brownish


  The color that the colonies of Corynebacterium produces in CTBA
• Corynebacterium


  In terms of their indentification, this genera is a catalase positive and a nonmotile bacteria
• 3 Corynebacterium which forms brown halo due to cysteinase activity:

  • Corynebacterium diphtheriae
  • Corynebacterium ulcerans
  • Corynebacterium pseudotuberculosis
• Corynebacterium diphtheriae


  A Corynebacterium specie that lacks urease production, producing acid, but not gas and reduces nitrate to nitrite
• glucose and maltose


  Carbohydrates which can ferment by Corynebacterium diphtheriae
• ELEK test


  It is known as In Vitro test for Corynebacterium to test for toxigenity (using immunodiffusion)
• Positive


  A reaction if there is presence of lines of precipitation in ELEK test
• Diphtheria antitoxin


  It is added with the filter paper strip in ELEK test that is placed in the center
• The diphtheria is treated by prompt administration of antitoxin