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MICRO & IMMUNO 

INDEX

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Aerobes vs. Anaerobes

Cocci

  • Bacillus

  • Clostridium

  • Corynebacterium

  • Listeria

  • Mycobacterium (acid-fast)

 

OTHERS​​​

  • Arcanobacterium

  • Bifidobacterium

  • Erysipelothrix

  • Eubacterium

  • Gardnerella

  • Lactobacillus

  • Propionibacterium

  • Staphyloccocus 

  • Streptococcus 

  • Enterococcus 

  • Peptococcus

  • Peptostreptococcus

  • Bartonella

  • Bordetella

  • Brucella

  • Campylobacter

  • Eikenella

  • Franciscella

  • Haemophilus

  • Helicobacter 

  • Moraxella

  • Neisseria

  • Veillonella 

  • ENTEROBACTERIACAE (Gut bugs)

    • Campylobacter

    • Citrobacter

    • Edwardsiella

    • Enterobacter

    • Escherichia coli

    • Hafnia

    • Klebsiella

    • Morganella

    • Proteus

    • Providencia

    • Salmonella

    • Serratia

    • Shigella

    • Yersinia

  • OTHERS

    • FERMENTATIVE

      • Aeromonas

      • Pasteurella

      • Plesiomonas

      • Vibrio

    • NON-FERMENTATIVE

      • Acinetobacter

      • Alcaligenes

      • Burkholderia

      • Flavobacterium

      • Pseudomonas

      • Stenotrophomonas

    • ANAEROBIC

      • Bacteroides

      • Fusobacterium

      • Porphyromonas

      • Prevotella

    • SILVER STAIN REQD.

      • Legionella​​

Coccobacilli

Rods/Bacilli

Tips for memorizing/learning the gram stain reactions:

 

Unfortunately, this requires a lot of memorization, but there are some basic tips to think about as you go along (adapted from Dr. Neal R. Chamberlain).

 

1. Memorize all of the cocci organisms. 

Most human pathogens are rods, so if you memorize which bugs are cocci, the rule of elimination leaves rods.​​

 

2. Memorize the gram-positive rods.

The list of gram pos rods is MUCCHHHH shorter than the list of gram neg rod

 

 

3. Know which bacteria are "unstainable" with routine gram stain. 

Some bugs require special stains or may be too small to be seen under regular light microscope. These include the organisms that do not have a cell wall, are obligate intracellular organisms and spirochetes. 

 

 

Classification of Bacteria:

Morphology + Gram Stain

GRAM POS

GRAM NEG

  • Anaplasma

  • Chlamydia

  • Chlamydophila

  • Coxiella

  • Ehrlichia

  • Orientia

  • Rickettsia

Spirochetes

  • Borrelia

  • Leptospira

  • Spirillum

  • Treponema ​

  • Mycoplasma

  • Ureaplasma

No Cell Wall

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Bacteria Morphology

SHAPE

Branching filaments

  • Actinomyces (anaerobic)

  • Nocardia (partially acid fast)

Obligate Intracellular

 

Continue to the next page to see how the bacterial organisms

are divided according to their oxygen requirements.

Unstainable Organisms

No Cell Wall

Other

  • Legionella (weakly gram neg rod- requires silver stain)

  • Mycobacterium tuberculosis

Miscellaneous

  • Borrelia

  • Leptospira

  • Spirillum

  • Treponema

    • ​Can't be seen with light microscope

  • Mycoplasma

  • Ureaplasma

Spirochetes

  • Anaplasma

  • Chlamydia

  • Chlamydophila

  • Coxiella

  • Ehrlichia

  • Orientia

  • Rickettsia

Obligate Intracellular

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