They are also known as Group A Streptococcus (GAS) or Group A (beta-hemolytic) Streptococcus (GABHS). Habitat of Streptococcus pyogenes They are found in the throat and skin of humans. They are commensals of the upper respiratory tract. The Carrier rate of S. … Read more
Habitat of Streptococcus pyogenes They are found in throat and skin of human. They are commensals of upper respiratory tract. Carrier rate of S. pyogenes in the respiratory tract is only few in adults, over 10% in children attending kindergarten. Opportunistic … Read more
1. Specimens Throat swab Pus Cerebrospinal fluid Blood Serum for antibody determinant 2. Smear Gram staining Purple color cocci in chain arrangement Not to be confused with Viridans Streptococci from throat swab sample since both have same appreance 3. Culture … Read more
Virulence factors of Streptococcus pyogenes A. Antigenic structure M protein: rod like coiled structure with two major structural classes; Class I and Class II ;major virulence factor;resist phagocytosis and intracellular killing by polymorphonuclear leukocytes in the absence of antibodies. B. … Read more
Biochemical Test of Streptococcus pyogenes Characteristics Properties (Streptococcus pyogenes) CAMP Negative (-ve) Capsule Capsulated Catalase Negative (-ve) Gram Staining Positive (+ve) Hemolysis Beta Motility Non-Motile OF (Oxidative-Fermentative) Fac. Anaerobes PYR Positive (+ve) Shape Cocci Spore Non-Sporing Urease Negative (-ve) VP … Read more
What is Bacitracin Susceptibility Test? Bacitracin susceptibility test is one of the antimicrobial disk tests for the identification of group A Streptococci from other β-hemolytic Streptococci. Antimicrobial susceptibility tests are mostly performed for the differentiation of different species of a … Read more
Biochemical reactions are very important in the identification of bacterial isolates and in the identification of different bacterial species. These tests depend on the presence of certain enzymes, such as catalase, oxidase, urease, gelatinase, etc., produced by the bacteria. Different … Read more