Medical Microbiology

Microscopic slides and media

Head of Microbiology Department and Laboratory Medical Immunology : Janina Grzegorczyk MD, PhD, professor

Implementators:

Małgorzata Brauncajs MD

Zbigniew Krzemiński MD, PhD, professor

Class 1. General microbiology – Morphology of bacterial cell, staining procedures for bacteria, culture media for bacteria, cultivation and isolation

techniques for bacteria, preparation of pure cultures.

Enriched media

Loeffler medium (slant for the detection of corynebacteria)

Loewenstein-Jensen medium (slant for the detection of mycobacteria)

Chromogenous bacterial strains

The pigment does not diffuse into the culture medium (Micrococcus sp., Staphylococcus sp.)

The pigment diffuses into the culture medium (Pseudomonas sp.)

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Class 1. General microbiology – Morphology of bacterial cell, staining procedures for bacteria, culture media for bacteria, cultivation and isolation

techniques for bacteria, preparation of pure cultures.

Class 1. General microbiology – Morphology of bacterial cell, staining procedures for bacteria, culture media for bacteria, cultivation and isolation

techniques for bacteria, preparation of pure cultures.

Microscopic slides – negative stain

Negatively stained Bacillus sp. – cylindrical shape

Negatively stained cocci – spherical shape

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Class 1. General microbiology – Morphology of bacterial cell, staining procedures for bacteria, culture media for bacteria, cultivation and isolation

techniques for bacteria, preparation of pure cultures.

Microscopic slide – capsule

Positive-negative stain

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Class 1. General microbiology – Morphology of bacterial cell, staining procedures for bacteria, culture media for bacteria, cultivation and isolation

techniques for bacteria, preparation of pure cultures.

Microscopic slides – endospores

A stained preparation of Bacillus subtilis showing endospores as uncoloured and the vegetative cell as violet – (Gram endospore stain)

A stained preparation of Bacillus subtilis showing endospores as green and the vegetative cell as red –(Schaeffer-Fulton endospore stain)

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Class 1. General microbiology – Morphology of bacterial cell, staining procedures for bacteria, culture media for bacteria, cultivation and isolation

techniques for bacteria, preparation of pure cultures.

Microscopic slides – flagella

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Class 3. General microbiology – Identification and classification of bacteria according to their biochemical and antigenic properties, determination of

bacterial resistance to the drugs.

Identification of bacteria based on its biochemical properties – API test

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Class 3. General microbiology – Identification and classification of bacteria according to their biochemical and antigenic properties, determination of

bacterial resistance to the drugs.

Two types of hemolysis

α-hemolysis (incomplete/green hue) β-hemolysis (complete)

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Class 3. General microbiology – Identification and classification of bacteria according to their biochemical and antigenic properties, determination of

bacterial resistance to the drugs.

Disc diffusion test

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Class 3. General microbiology – Identification and classification of bacteria according to their biochemical and antigenic properties, determination of

bacterial resistance to the drugs.

Etest, Epsilometer test (MIC – minimal inhibitory concentration); MIC = 0,125

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Class 3. General microbiology – Identification and classification of bacteria according to their biochemical and antigenic properties, determination of

bacterial resistance to the drugs.

MRSA – Methicillin-resistant Staphylococcus aureus

Determination of S. aureus sensitivity to methicillin with cefoxitin disc

Determination of S. aureus sensitivity – review method

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Identification of staphylococci in selective-differential medium – mannitol salt agar (Chapman’s medium). Mannitol-positive staphylococci (S.aureus) – a change in the pigmentation of the medium from pink to yellow can be seen; mannitol-negative staphylococci (S.epidermidis) – no change in the pigmentation

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Class 5. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; Gram-positive facultative cocci (genus Staphylococcus,

Streptococcus and Enterococcus).

Class 5. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; Gram-positive facultative cocci (genus Staphylococcus,

Streptococcus and Enterococcus).

Rapid distinction between micrococci and staphylococci with furazolidone disc: micrococci on the left side (resistant), staphylococci on the right side (susceptible)

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Class 5. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; Gram-positive facultative cocci (genus Staphylococcus,

Streptococcus and Enterococcus).

Staphylococcus aureus – Gram stain (Gram-positive cocci forming structures similar to wine grapes)

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Class 5. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; Gram-positive facultative cocci (genus Staphylococcus,

Streptococcus and Enterococcus).

The bacitracin (SP disc) test for identifying Streptococcus pyogenes

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The optochin (OP disc) test for identifying Streptococcus pneumoniae

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Class 5. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; Gram-positive facultative cocci (genus Staphylococcus,

Streptococcus and Enterococcus).

Class 5. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; Gram-positive facultative cocci (genus Staphylococcus,

Streptococcus and Enterococcus).

Streptococcus pyogenes – Gram stain (Gram-positive cocci forming long chains)

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Class 5. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; Gram-positive facultative cocci (genus Staphylococcus,

Streptococcus and Enterococcus).

Streptococcus pneumoniae in tissue – Gram stain (Gram-positive cocci forming diplococci with capsule)

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Class 5. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; Gram-positive facultative cocci (genus Staphylococcus,

Streptococcus and Enterococcus).

Enterococcus faecalis – Coccosel-agar medium.

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Class 5. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; Gram-positive facultative cocci (genus Staphylococcus,

Streptococcus and Enterococcus).

Enterococcus faecalis – Gram stain (Gram-positive cocci forming pairs or short chains)

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

Neisseria gonorrhoeae – Gram-stained urethral discharge

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

Treponema pallidum – Giemsa stain (spiral shape)

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

C.diphtheriae – Neisser stain (violet storage cells) C.diphtheriae – Gram stain (Gram-positive, highly pleomorphic organisms with no particular arrangement)

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

C.pseudodiphteriticum – Neisser stain (without storage cells)

C.pseudodiphteriticum – Gram stain (Gram-positive rods, frequently show club-shaped swellings and palisade arrangement)

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

Actinomyces israelii – Gram stain (Gram-positive bacteria that form long, branching filaments resembling the fungi)

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

Growth of the species belonging to Mycobacterium in the Loewenstein-Jensen medium: (test tube nr 1 – Nocardia spp. – agar slant; test tubes nr 2 and 3 –

mycobacteria in the L-J medium)

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

Bogen‘s test

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

Biochemical tests for mycobacteria (test tube nr 1 – niacin test, nr 2 – Nocardia spp. – slant, test tube nr 3 – Bogen’s test)

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

Niacin test

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

Mycobacterium tuberculosis – Ziehl-Neelsen stain: (acid-fast , red-stained mycobacteria)

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Class 6. Oral microbiology – Bacteria causing inflammations and abscesses within the oral cavity; acid-fast bacteria (genus Mycobacterium), Gram-

positive non-sporulating bacilli (genus Corynebacterium, Actinomyces), Gram-negative aerobic cocci (genus Neisseria) and spirochetes (genus Treponema).

The antimicrobial susceptibility of Mycobacterium tuberculosis H37Rv

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Class 8. Oral microbiology – Bacteriology of dental caries and periodontal diseases.

Anaerobic Gram-negative bacteria – Gram stain.

Bacteroides sp. (Gram-negative bacteria,short, pleomorphic rods)

Fusobacterium sp. ( Gram-negative bacteria, thin, long, usually sharp-ended rods)

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Anaerobic Gram-positive bacteria – Gram stain

Propionibacterium sp. (Gram-positive bacteria, cylindrical, pleomorphic cells)

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Class 8. Oral microbiology – Bacteriology of dental caries and periodontal diseases.