Staphylococcus spp.

review well!!

Gram positive cocci

*Staphylococcus spp. Micrococcus spp. Streptococcus spp*

Family name for Staphylococcus spp.

Staphylococcaceae

It is Catalase (+), Coagulase (+) but some are CONS, and Gram (+) cocci in singly, in pairs, and in GRAPE-LIKE clusters.

*Staphylococcus spp.*

breakdown of hydrogen peroxide (H202) to water (H20) and Oxygen (O2)

Catalase (+)

It is the color for medium sized- pinhead colonies and opaque for *Staphylococcus*

Yellow Pigment

Give the 3 gram positive cocci that covered with *Staphylococc*i and known for its acronym ‘**R.A.A**’

Rothia mucilaginosa, Aerococcus, & Alloiococcus otitis (recovered with external ear fluid)

except: *M. kris*tinae & *M. varians*

Catalase (+) for Staphylococci & Micrococci except: *S. sciuri, Macrococcus caseolyticus, S. lentus, & S. vitulus* because they are Catalase (-)

What is the greek term that means “bunches of grapes”

Staphle

medium sized (4 to 8mm) and appear cream-colored, white or rarely light gold, and “**BUTTERY-LOOKING**”

*Staphylococcus spp.*

**Infection:** Nosocomial infections- common cause of healthcare-acquired UTI

*Staphylococcus epidermidis*

**Infections:** Wound, Septicemia, UTIs, & native valve infections

*Staphylococcus haemolyticus*

**Infection:** Catheter- related bacteremia and endocarditis

*Staphylococcus lugdunensis*

**Infections:** UTI (in adolescent girls & young women), & second common cause of UTI after *E. coli*

*Staphylococcus saprophyticus*

**Infection**: Rarely implicated in infections

*Micrococcus spp. Kocuria spp. & Kytococcus spp.*

**Part of the Virulence factors for Staphylococcus aureus:**

* Resistance to hydrolysis by the gastric and intestinal enzymes
* Groups A-E & G-J
* Heat stable exotoxins (100 C for 30 minutes)

Enterotoxins

**Virulence factor for Staphylococcus aureus:** __**ENTEROTOXINS**__

* What letters is for __Staphylococcal food poisoning__?

A-E

**Virulence factor for Staphylococcus aureus:** __**ENTEROTOXINS**__

* What are the groups for __TSS (toxic shock syndrome)__?

Group B, C, G, & I

**Virulence factor for Staphylococcus aureus:** __**ENTEROTOXINS**__

* What group is for __Staphylococcal pseudomembranous enterocolitis__?

Group B

**Part of the Virulence factors for Staphylococcus aureus:**

* systemic effects incl. fever and hypotension
* TSS
* previously known as **enterotoxin F** (pyrogenic exotoxin)

Toxic Shock Syndrome Toxin-1

**Part of the Virulence factors for Staphylococcus aureus:**

* cause epidermal layer of the skin to peeling
* Epidermolytic toxin A & B
* **Bullous impetigo**

Exfoliative Toxin

It is part of the Exfoliative Toxin and other term for Staphylococcal SSS

Ritter disease

Part of the Virulence factors for Staphylococcus aureus:

* extracellular proteins that affect red blood cells and leukocytes
* **Lysins** & **leukocidins**

Cytolytic Toxin/ Cytoxin

**Cytolytic toxin/ Cytoxin**

* it disrupts the smooth muscle in blood vessels and is __toxic to erythrocytes, leukocytes, hepatocytes, and platelets__- severe tissue damage

α-hemolysin

Cytolytic toxin/ Cytoxin

* also known as ‘**Sphingomyelinase C**’ or ‘**Hot-cold lysin**’
* acts on sphingomyelin in the plasma membrane of RCBs
* act in **CAMP test**
* enhanced hemolytic activity on incubation at 37 C and subsequent exposure to cold at 4 C

β-hemolysin

**Cytolytic Toxin** (*S. aureus, S. epidermidis, & S. haemolyticus*)

* __less toxic__ than a-hemolysin or B-hemolysin
* Some CONS

ƍ-hemolysin (delta)

**Cytolytic Toxin** (*S. aureus, S. epidermidis, & S. haemolyticus*)

* __functions with (PVL)__ Panton-Valentine leukocidin

y-hemolysin (gamma)

**Staphylococcal leucocidin**

* Exhibit polymorphonuclear leukocyte toxicity

Panton-Valentine leukocidin

**Part of the Virulence factors for Staphylococcus aureus:**

* Coagulase, protease, hyaluronidase, & lipase

Enzymes

**Part of the Virulence factor** __**ENZYME**__**:**

* permits the bacteria to __spread to connective tissues__
* __hydrolyzes hyaluronic acid present in the intracellular ground substance__ that makes up connective tissues, permitting the spread of bacteria during infection

Hyaluronidase

**Part of the Virulence factor** __**ENZYME**__**:**

* positive tube coagulase test
* clot/clump formation
* *S. intermedius, S. pseudointermedius, S. hycius, S. lutrae, S. agnetis, and some S. schleiferi*

Staphylocoagulase

**Part of the Virulence factor** __**ENZYME**__**:**

* **degrades lipids on the skin** making it more susceptible to bacterial entry into epidermal layers
* by both coagulase (+) and CoNS
* __act on lipids__ present on the surface of the skin

Lipase

Part of the Virulence factors for Staphylococcus aureus:

* found in the cell wall
* **bind the Fc portion of immunoglobulin G (IgG) and complement**
* __block phagocytosis__ and __inhibit action of IgG__

protein A

Part of the Virulence factors for Staphylococcus aureus:

* provides __rigidity of cell wall__
* activates complement, **IL-1** (Interleukin1-endogenous pyrogen-induces fever), **chemotactic to PMNs** (polymorphonuclear leukocytes)

Peptidoglycan

Part of the Virulence factors for Staphylococcus aureus:

* cell wall metabolism
* mediate __**binding to fibronectin**__

Teichoic acid

Is *Staphylococcus aureus* a halophilic (salt loving)?

Yes

The color of Mannitol fermenter and Non-mannitol fermenter

Mannitol is YELLOW colonies while the Non-Mannitol is PINK colonies

Macroscopic examination of *Staphylococcus aureus*:

* **round, smooth, white, creamy colonies on BAP**

S. aureus

Macroscopic examination of *Staphylococcus aureus*:

* **small-medium-sized, non-hemolytic (gamma), gray-to-white colonies**

S. epidermidis

Microscopic examination- gram staining

* Gram (+) cocci in singly, in pairs and in grape-like clusters

Staphylococcus aureus

pics

* identification of methicillin-resistant staphylococcus aureus

CHROMagar

name it

HiChrome agar

**What Biochemical Test of** ***Staphylococcus aureus*** **is this?**

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__**Principle:**__ catalase mediates the breakdown of hydrogen peroxide (30% H202) into oxygen and water (produces bubbles)

Catalase

**Result for Catalase (biochemical test):**


1. (+) bubble formation (?)
2. (-) no or few bubble formation (?)

1. *Staphylococcus spp.* & *Micrococcus spp.*
2. *Streptococcus*

**What Biochemical Test of** ***Staphylococcus aureus*** **is this?**

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__**Principle:**__ oxidase enzyme reacts with the oxidase reagent and cytochrome C to form the colored compound, indophenol after 2 mins

Microdase test/ Modified oxidase test

**Result for Microdase test (biochemical test):**


1. (+) development of blue to purple-blue color (?)
2. (-) no color change (?)

1. *Micrococcus spp.*
2. *Staphylococcus spp.*

**What Biochemical Test of** ***Staphylococcus aureus*** **is this?**

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__**Principle**__: determine the effect of a small amount of bacitracin ==**(0.04 U)**== on an organism

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* ==Vernier caliper or ruler== to measure it
* Incubate for 18-24 hours

Bacitracin test

**Result for Bacitracin test (biochemical test):**


1. (+) presence of zone of inhibition around the disk (?)
2. (-) no zone of inhibition (?)

1. greater than (>) 10mm susceptible
2. less than (

**What Biochemical Test of** ***Staphylococcus aureus*** **is this?**

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__**Principle**__: determine whether an organism uses carbohydrate substrates to produce acid by products using OF glucose medium

Oxidation-Fermentation (O/F) reactions

**Result for Oxidation-Fermentation (O/F) reactions (biochemical test):**


1. (+) yellow medium (?)
2. (-) green medium (?)

1. acid production- Glucose, xylose, mannitol, lactose, sucrose, and maltose
2. no acid production- *Micrococcus spp.* except M. kristinae & M. varians

Oxidation-Fermentation (O/F) reactions

* observe the fermentative utilization of carbohydrate in both __**open & close tubes**__
* __**single acid**__ (homolactic acid fermenters)
* __**mixed acids**__ (lactic acid, propionic acid & succinic acid)

Fermentation

Oxidation-Fermentation (O/F) reactions

* only result in acid production on an __**open tube only**__
* requires oxygen (aerobic respiration)
* inorganic molecule (anaerobic respiration)

Oxidation

**What Biochemical Test of** ***Staphylococcus aureus*** **is this?**

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__**Principle**__: used to differentiate Staphylococcus aureus from CoNS by detecting enzyme coagulase

Coagulase test

**Result for Coagulase test (biochemical test):**


1. (+) fibrin clot (?)
2. (-) no fibrin clot (?)

1. *Staphylococcus aureus*
2. CoNS

What form of coagulase enzyme is this?

* Known as Slide Coagulase Test
* bound to the bacterial cell wall and reacts directly with fibrinogen in plasma
* Fibrin clot (clumping of cells)- (+) S. aureus, S. lugdunensis, & S. schleiferi

Reagent- Rabbit’s plasma/Human/Pig plasma (EDTA)

Bound coagulase/clumping factor

What form of coagulase enzyme is this?

* Known as Tube Coagulase Test
* extracellular protein enzyme (free coagulase) + CRF (coagulase-reacting factor)
* Fibrin clot- possibility of autolysis due to fibrinolysin

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0\.5 ml Rabbit’s plasma + emulsify the organism

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Free coagulase/Staphylocoagulase

**What Biochemical Test of** ***Staphylococcus aureus*** **is this?**

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__**Principle**__: differentiate S. aureus from other CoNS by the presence of the enzyme L-pyrroglutamylaminopeptidase

* bright red precipitate

Pyrrolidonyl Arylamidase (PYR) Test

**Result for Pyrrolidonyl Arylamidase (PYR) test (biochemical test):**


1. (+) Bright red color (?)
2. (-) No color change or an orange color

1. S. lugdunensis, S. intermedius, S. schleiferi
2. S. aureus

**What Biochemical Test of** ***Staphylococcus aureus*** **is this?**

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__**Principle**__: determine the ability of some organisms to produce neutral end products from glucose fermentation (check if organism are able to produce acetyl-methylcarbinol or acetoin from glucose)

Vogue-Proskauer (VP) Test

**Result for Vogue-Proskauer (VP) test (biochemical test):**


1. (+) Red color (?)
2. (-) Yellow color (?)

1. S. aureus
2. S. intermedius (human infection associated with animal bites), S. lugdunensis, S. haemolyticus, & S. schleiferi

**What Biochemical Test of** ***Staphylococcus aureus*** **is this?**

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__**Principle**__: determine the ability of an organism to hydrolyze DNA based in the production of deoxyribonuclease

* medium is pale green because of the DNA-methyl green complex

DNA hydrolysis

Result for DNA hydrolysis (biochemical test):


1. (+) Clear (?)
2. (-) Green (?)

1. S. aureus
2. none

**What Biochemical Test of** ***Staphylococcus aureus*** **is this?**

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Principle: determine the effect of a ==**5-ug novobiocin disk**== on an organism

Novobiocin Susceptibility Test

Result for Novobiocin Susceptibility Test (biochemical test):


1. (+) presence of zone of inhibition around the disk (?)
2. (-) no zone inhibition (?)

1. Greater (>) than 16mm-
* CoNS, S. epidermidis, S. capitis, S. haemolyticus, S. hominis subsp. hominis, S. lugdunensis, Saccharolyticus, & S. warneri
2. Less (

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* Penicillin-resistant (**β-lactam)** strains of S. aureus
* TOC: **Vancomycin**

MRSA (methicillin-resistant Staphylococcus aureus)

* Resistance to **clindamycin** (Treat for pimples)
* modified double disk diffusion test (D-zone test)

Macrolide Resistance