STAPHYLOCOCCI-AND-OTHER-CATALASE-POSITIVE-GRAM-POSITIVE-COCCI

Catalase

Catalase

An enzyme that breaks down hydrogen peroxide into water and oxygen.

Resident flora

Microorganisms that normally live on the skin and mucous membranes.

Infections

The invasion and multiplication of microorganisms in the body, causing harm.

Planococcus

A genus of bacteria that are free-living saprophytes.

Stomatococcus

A genus of bacteria that are normal flora of primates and other mammals.

Lysostaphin

An enzyme that cleaves the peptidoglycan of Staphylococcus bacteria.

Modified Oxidase Test

A test used to determine the presence of the enzyme cytochrome oxidase in bacteria.

Oxidase Reagent

A reagent used to detect the presence of cytochrome oxidase.

Bacitracin

An antibiotic that inhibits the growth of certain bacteria, used in the bacitracin susceptibility test.

Hugh & Leifson's medium

A medium used for the OF test.

Staphylococcus aureus

A species of Staphylococcus bacteria that is clinically significant and a cause of nosocomial infections.

Staphyloxanthin

A pigment produced by some strains of Staphylococcus aureus, giving colonies a golden yellow color.

Coagulase Test

A test used to differentiate Staphylococcus aureus from other Staphylococcus species based on their ability to produce the enzyme coagulase.

Clumping Factor

A component of Staphylococcus aureus that reacts with fibrinogen, leading to the formation of clumps.

Tube Coagulase Test

Definition:A biochemical test used to confirm the presence of Staphylococcus aureus by detecting the production of coagulase enzyme. A positive result indicates the presence of the bacteria.

Protein A

Definition:A virulence factor produced by Staphylococcus aureus that binds to the antibody molecule, interfering with phagocytosis and complement fixation.

Hyaluronidase

Definition:An enzyme produced by Staphylococcus aureus that hydrolyzes hyaluronic acid present in connective tissues, allowing the spread of infection.

Panton-Valentine Leukocidin (PVL)

Definition:A cytolytic toxin produced by some strains of Staphylococcus aureus. It is lethal to polymorphonuclear leukocytes (PMNs) and contributes to the invasiveness of the bacteria.

Pyogenic

Definition:Referring to an infection characterized by the formation of pus. Staphylococcus aureus infections are often pyogenic in nature.

Scalded Skin Syndrome (SSS)

Definition:A skin infection caused by Staphylococcus aureus producing exfoliative toxins A and B. It results in the separation of the dermis and is also known as Ritter Lyell disease.

Staphylococcus epidermidis

Definition:A species of coagulase-negative Staphylococcus that is commonly found on the skin and mucous membranes. It is often associated with infections in immunosuppressed patients and is a frequent cause of bacterial endocarditis following the insertion of artificial heart valves.

Columbia Colistin-nalidixic acid agar (CNA)

A selective medium used to isolate Gram-positive bacteria, including Staphylococcus species.

MRSA

Methicillin-resistant Staphylococcus aureus, a strain of Staphylococcus aureus that is resistant to multiple antibiotics.

Viridans

Streptococci that grow at 45°C and include species such as S. salivarius and S. mutans.

Alpha hemolytic

Partial hemolysis of red blood cells (RBCs) accompanied by a greenish discoloration. Examples include S. pneumoniae and S. viridans.

Beta hemolytic

Complete hemolysis of RBCs indicated by a clear colorless zone of hemolysis surrounding the colonies. Examples include S. pyogenes and S. agalactiae.

Group A Streptococcus (S

Streptococcus species that belong to Lancefield Group A and are associated with a wide range of diseases.

Streptolysin O (SLO)

A membrane-damaging toxin produced by hemolytic streptococci.

Streptokinase

An enzyme produced by Group A Streptococcus that dissolves blood clots.

Salt Tolerance Test

Differentiates Group D Streptococci from Enterococcus

Streptococcus pneumoniae

Polysaccharide capsule - A major virulence factor with many serologic variations.

Streptococcus pneumoniae

Disease Association - Most common cause of bacterial pneumonia and the second most common cause of bacterial meningitis. Also associated with otitis media, purulent sinusitis, and peritonitis.

Bile Solubility Test - Used to confirm equivocal results in the Optochin test

Algorithm for Identification - A flowchart for identifying S

Pelvic inflammatory disease (PID)

a complication of gonorrhoea in women that can lead to infertility, ectopic pregnancy, and perihepatitis

Perihepatitis (Fitz-Hugh-Curtis syndrome)

inflammation of the membrane lining the stomach (peritoneum) and the tissues surrounding the liver (perihepatitis)

Gono-Pak

a commercial transport system for specimens containing Neisseria gonorrhoeae

CTA Medium

cystine trypticase agar medium used for carbohydrate utilization test

Matrix-Assisted Laser Desorption/Ionization – Time-of-Flight Mass Spectrometry (MALDI-TOF MS)

a technology used to identify microorganisms based on their unique protein signatures

Crowded living conditions

Living in close quarters with a large number of people, increasing the risk of transmission of infectious diseases.

BAP

Blood agar plate, a type of culture medium used to grow bacteria.