write at least 3 virulence factors for staph strep A strep B

write at least 3 virulence factors for staph, strep A, strep B, strep D, pneumococcus, Nisseria Meningo, nisseria gonorrhoeae, haemophilus

Staphylococcus expresses many potential virulence factors. They are :

(1) surface proteins that induces colonization of host tissues

(2) invasins that helps in bacterial spread in tissues (leukocidin, kinases, hyaluronidase);

(3) surface factors that resist phagocytic engulfment (capsule, Protein A);

(4) biochemical properties that increase their chance of survival in phagocytes (carotenoids, catalase production);

(5) immunological disguises like Protein A, coagulase;

(6) membrane-damaging toxins that lyse eucaryotic cell membranes (hemolysins,leukotoxin, leukocidin;

(7) exotoxins that destroy host tissues or provoke symptoms of disease (SEA-G, TSST, ET);

(8) inherent and acquired resistance to antimicrobial agents

Streptococcus pyogenes (Group A streptococcus) expresses the following virulence factors :

(1) M protein, fibronectin-binding protein (Protein F) and lipoteichoic acid that help in adherence

(2) hyaluronic acid capsule which acts as an immunological disguise and inhibits phagocytosis;

(3) invasins such as streptokinase, streptodornase (DNase B), hyaluronidase, and streptolysins;

(4) exotoxins, such as pyrogenic (erythrogenic) toxin which forms the rash of scarlet fever and systemic toxic shock syndrome.

Streptococcus agalactiae ( Group B streptococcus ) expresses the following virulence factors :

(1) capsular polysaccharides, which confer serotype specificity to GBS

(2) C proteins and other related surface proteins

(3) Pilins function as adhesins, promote CNS entry, and enhance biofilm formation

(4) a pore-forming toxin, -hemolysin, that today is considered identical to the GBS pigment

Group D Streptococci have been reclassified and placed in the genus Enterococcus. The virulence factors are :

(i) adherence to host tissues facilitated by aggregation substance, surface carbohydrates, or fibronectin-binding moieties

(ii) invasion and abscess formation,

(iii) factors potentially relevant to modulation of host inflammatory responses,

(iv) potentially toxic secreted products

(v) Extracellular toxins such as cytolysin can induce tissue damage

The pneumococcus virulence factors are :

(1) the choline-binding proteins;

(2) pneumococcal surface proteins A and C (PspA and PspC);

(3) the LPXTG-anchored neuraminidase proteins; hyaluronate lyase (Hyl);

(4) pneumococcal adhesion and virulence A (PavA);

(5) enolase (Eno); pneumolysin; autolysin A (LytA)

The virulence factors of Neisseria meningitidis are :

(1) Capsules whose presence provide resistance against antibody, complement-mediated, or phagocytic destruction by the host immune response

(2) lipooligosaccharides cause variation via frameshift mutations which allows the pathogen to circumvent the host immune response

(3) adhesion factors like type IV pili, Opa and Opc

Virulence Factors of Nisseria gonorrhoeae are :

(1) Capsule which is antiphagocytic

(2) Pili which mediate initial attachment of gonococci to epithelial cells.

(3) Outer Membrane Proteins like Por (protein I), Opa (protein II), Rmp (protein III), Tbp1, Tbp2, Lpb

Haemophilus influenzae expresses the following virulence factors :

(1) outer membrane lipooligosaccharide (LOS) plays a role in inflammation

(2) the capsular polysaccharide which contains ribose, ribitol and phosphate

(3) polyribosyl ribitol phosphate (PRP) capsule is an important virulence factor as it renders type b H. influenzae resistant to phagocytosis