organism list

• Which organism is a Gram-positive diplococcus?

  Streptococcus pneumoniae
• What are the Gram-negative diplococci mentioned in the material?

  Neisseria spp., Moraxella catarrhalis
• What are the types of Gram-positive bacilli and their characteristics?

  • Small: Listeria monocytogenes, Corynebacterium diphtheriae
  • Medium: Lactobacillus, anaerobic bacilli
  • Large: Clostridium, Bacillus anthracis
  • Diphtheroid: Corynebacterium spp., Propionibacterium spp., Rothia spp.
  • Pleomorphic: Gardnerella vaginalis
  • Beaded: Mycobacterium spp., antibiotic-affected lactobacilli
  • Filamentous: Anaerobic morphotypes, antibiotic-affected cells
  • Filamentous branched: Actinomycetes spp., Nocardia spp., Nocardiopsis spp., Streptomyces spp., Rothia spp.
  • Beaded branched: Bifidobacterium spp., brevibacteria
• What are the Gram-negative coccobacilli mentioned?

  Bordetella spp., Haemophilus spp.
• What are the types of Gram-negative bacilli and their characteristics?

  • Small: Haemophilus ducreyi, Legionella spp.
  • Bipolar: Klebsiella pneumoniae, Pasteurella spp., Bacteroides spp.
  • Medium: Enterics, Pseudomonas
  • Large: Devitalized clostridia or bacilli
  • Curved: Vibrio spp., Campylobacter spp.
  • Spiral: Campylobacter spp., Helicobacter spp., Gastrobacillus spp., Borrelia spp., Leptospira spp., Treponema spp., Spirillum minor
  • Fusiform: Fusobacterium nucleatum
  • Filaments: Fusobacterium necrophorum
• How are small Gram-positive bacilli like Listeria monocytogenes arranged?

  They are arranged in various shapes including club-shaped.
• What is a characteristic arrangement of Haemophilus ducreyi?

  Arranged in school of fish appearance
• How do the arrangements of Gram-positive cocci differ from Gram-negative bacilli?

  Gram-positive cocci can form clusters, while Gram-negative bacilli can be curved or spiral.
• Which Gram-positive organism is known for its encapsulated form?

  Streptococcus pneumoniae
• What is the appearance of Campylobacter spp.?

  S or C shaped resembling seagull wings
• Which organism is described as having a tightly twisted spiral shape?

  Treponema spp.
• What does the term "pleomorphic" refer to in the context of Gardnerella vaginalis?

  It means the organism can have various shapes.
• How do the arrangements of Actinomycetes spp. differ from those of Bifidobacterium spp.?

  Actinomycetes spp. are filamentous, while Bifidobacterium spp. are bifid or V-shaped.
• What is the significance of identifying encapsulated organisms like Streptococcus pneumoniae in clinical bacteriology?

  They are often associated with virulence and disease.