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Chocolate agar with factors V (NAD⁺) and X (hematin)

H. Influenzae

Thayer-Martin (or VPN) media - Vanco inhibits gram(+) organisms, Polymyxins inhibits gram (-) organisms, and Nystatin inhibits fungal organisms.

Neisseria Gonorrhoeae

Bordet-Gengou (potato) agar

Bordetella Pertussis

Cystine-Tellurite Plage, Loffler's media

C. Diphtheriae

Lowenstein-Jensen agar

M. Tuberculosis

Eaton's Agar

Mycoplasma Pneumoniae

MacConkey's agar (fermentation produces acid, turning plate pink.

Lactose-fermenting enterics

Eosin-methylene blue agar, blue-black colonies with metallic sheen

E. Coli

Charcoal Yeast extract agar

Legionella

Sabouraud's agar

Fungi

Giemsa stain

Borrelia, Plasmodium, Trypanosomes, Chlamydia

PAS - stains glycogen, mucopolysaccharrides

Topheryma Whippleii

Ziehl-Neelsen

Acid-fast organisms (mycolic acids)

India Ink(negative stain)/Mucicarmine(pink)

Cryptococcus neoformans

Silver stain

Fungi (e.g. pneumocytis), Legionella

KOH preparation

dermatophytes

Catalase test

Differentiates Staphylococcus from Streptococcus

Coagulase test

Differentiates S. Aureus from S. epidermidis/saprophyticus

Novobiocin sensitivity

Differentiates S. epidermidis (sensitive) from S. saprophyticus (resistant)

Gamma hemolytic

No hemolysis - Enterococcus (E. feacalis), Peptostreptococcus, S. Bovis

6.5% NaCl test

Differentiates E. Feacalis (positive) from S. Bovis (negative)

Optichin sensitivity

Differentiates S. Pneumoniae (sensitive) from Viridans Streptococci (resistant)

Alpha hemolytic

Partial hemolysis/green - S. Pneumoniae, Viridans Strep, and some Group D Strep

Growth on Bile-esculin agar (extremely salt resistant)

Group D streptococci

Beta Hemolytic

Complete hemolysis - Group A S. pyogenes and Group B S. agalactiea. Also S. Aureus and Listeria Monocytogenes.

Bacitracin sensitivity

Differentiates S. Pyogenes (sensitive) from S. Agalactiae (resistant)

CAMP test (produces CAMP factor)

Group B streptococcus (agalactiae)

Maltose Fermentation test

Differentiate Neisseria species - N. Meningitidis (fermenter), N. Gonorrhoeae (non-fermenter)

Lactose fermentation test

Differentiates gram (-) rods from each other.

Fast Lactose fermenters

Klebsiella, E. Coli, Enterobacter

Slow Lactose fermenters

Citrobacter, Serratia

Oxidase test

Differentiates Lactose Non-fermenters from each other.

Oxidase(+), Lactose non-fermenters

Pseudomonas

Oxidase(-), Lactose non-fermenters

Shigella, Salmonella, Proteus

Obligate aerobes

Nocardia
Pseudomonas aeruginosa
Mycobacterium tuberculosis
Bacillus

Obligate anaerobes; Aminoglycosides ineffective, susceptible to oxidative damage.

Clostridium
Bacteroides
Actinomyces

Obligate intracellular bugs; can't make own ATP

Ricketsia
Chlamydia

Facultative Intracellular bugs

Salmonella
Neisseria
Brucella
Mycobacterium
Listeria
Francisella
Legionella

Encapsulated bacteria (+ Quellung); antiphagocytic virulence factor --> require opsonization for clearance.

Klebsiella
Salmonella
S. pneumoniae
H. Influenzae B
Neisseria meningitidis

Urease + bugs

Proteus
Ureaplasma Urealyticum
H. Pylori
Klebsiella

Yellow pigment production

S. Aureus

Blue-green pigment

Pseudomonas aeruginosa

Red pigment

Serratia marcescans

IgA protease production; used to colonize respiratory mucosa

S. pneumoniae
H. influenzae B
N. meningitidis

M protein; prevent phagocytosis

Group A streptococcus

Protein A; binds Fc region of Ig, preventing opsonization and phagocytosis

S. Aureus

cAMP inducers; activate host adenylate cyclase, or are themselves adenylate cyclase.

Vibrio cholerae - activates Gs
Pertussis toxin - disables Gi
E. Coli (ETEC) - heat labile toxin
Bacillus anthracis - bacterial adenylate cyclase

Superantigens

Bind directly to MHC II and TCRs simultaneously, activating large #'s of T cells to stimulate release of IFN-γ and IL-2 --> septic shock.

S. aureus toxins

TSST-1 = toxic shock syndrome

Enterotoxin A = food poisoning (preformed), in meat, mayo, and creamy pastry dishes; nausea and vomitting 3-6 hours after eating, little to no diarrhea.

Exfoliatin = staphylococcal scalded skin syndrome

S. pyogenes toxin

Erythrogenic toxin = toxic shock-like syndrome; assoc. with scarlett fever.

ADP ribosylating A-B toxins

Interfere with host cell function by entering host cell and altering protein fxn from within.

Corynebacterium diphtheriae toxin

Inactivates EF-2; causes pharyngitis and pseudomembrane in throat.

Pseudomonas aeruginosa toxin (ecthyma gangrenosum)

Inhibits EF-2; similar to diphtheria toxin.

Vibrio cholerae toxin

ADP ribosylation of G protein stimulates adenylyl cyclase; increases pumping of Cl⁻ into gut and decreases Na⁺ absorption. H₂O moves into gut lumen causing voluminous rice-water (secretory) diarrhea.

ETEC toxin

Heat-labile toxin stimulates Adenylate cyclase. Heat-stable toxin stimulates Guanylate cyclase. both cause watery/secretory diarrhea.

Bordatella pertussis toxin

Gram (-) aerobic bacillus, causes whooping cough (coughing, choking spells, and gasping for air);

Toxin inactivates inhibitory subunit of the G protein complex, activating adenylate cyclase, increasing cAMP in the cells of the respiratory system >> EDEMA. Toxin also causes LYMPHOCYTOSIS by blocking chemokine receptors, blocks the function of immune effector cells and increases HISTAMINE SENSITIVITY. Toxin also alters hormonal pathways regulated by cAMP, increasing insulin secretion, causing HYPOGLYCEMIA.

Tx: erythromycin

Bacillus Cereus Toxin

Heat-stable toxin causing vomiting. From rice in the buffet line. Onset in less than 6 hours.

Clostridium perfringens toxin

α toxin causing gas gangrene; get double zone of hemolysis on blood agar.

C. tetani toxin

Blocks release of inhibitory GABA and glycine; causes spastic paralysis.

C. botulinum toxin

Blocks the release of ACh; causes anticholinergic symptoms, CNS flaccid paralysis, especially cranial nerves; spores found in canned food, honey (floppy baby).

Differentiate from all other anticholinergic drugs (e.g. atropine)by the presence of muscle weakness or paralysis.

Bacillus anthracis toxin

Edema factor is an adenylate cyclase, increases cAMP.

Shigella/EHEC toxin

Shiga toxin/verotoxin; cleaves host rRNA (inactivate 60S); enhances cytokine release, causes Hemolytic-uremic syndrome.

S. pyogenes toxin

Streptolysin O is a hemolysin; antigen for ASO antibody is used for rheumatic fever diagnosis.

Endotoxin

Lipopolysaccharide found in outer membrane of all gram (-) bacteria (and listeria monocytogenes); Lipid A is toxic component.
Activates macrophages, alternative complement pathway, and Hageman factor to produce septic shock and DIC. Secretion of IL-1, IL-6, and TNFα

Bacterial toxins encoded on lysogenic phage

ShigA-like toxin
Botulinum toxin
Cholera toxin
Diphtheria toxin
Erythrogenic toxin (S. pyogenes)
O-antigen salmonella

Transformation

Ability to take up DNA from environment; S. pneumoniae, H. influenzae, Neisseria.

Conjugation

Transfer of plasmid encoded virulence factors from one bacteria to another via pilus formation.

Transduction

Transfer of bacteria DNA through incorporation of DNA into bacteriophage.

Site-specific Transduction: specific sequence, error of temperate virus life-cycle.
Generalized Transduction: random bacterial DNA, error of lytic virus life-cycle.

Transposition

segments of DNA that can jump from one section of DNA to another, or from chromosome into phage DNA and viceversa.

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