Table 1.
Secreted virulence factors involved in survival in the bloodstream | |||
---|---|---|---|
Name | Gene | Proposed functiona | Virulence defect associated with loss of geneb |
Adenosine synthase | adsA | Synthesis of immune suppressors Ado, dAdo | Decreased survival in blood |
Nuclease | nuc | Degradation of NETs | Decreased survival in blood |
Clumping factor A | clfA | Agglutination | Increased phagocytic uptake |
Coagulases |
coa vwb |
Agglutination | Increased phagocytic uptake |
Protein A (SpA) | spa | Binding of the Fcγ domain of Igs | Increased opsonization and phagocytosis of bacteria |
Leukocidins |
hlgAB hlgCB lukAB |
Lysis of leukocytes | Unknown Unknown Decreased survival in blood |
Fibronectin-binding repeat protein A, B |
fnBPA fnBPB |
Recognition of fibronectin-FnBR complexes by α5β1 integrin; fibrinogen binding | Unknown |
Staphylococcal complement inhibitor (SCIN), SCIN-B, SCIN-C |
scin scinB scinC |
Blockage of C3 convertases | Unknown |
Extracellular complement–binding protein | ecb | Blockage of C3 convertases | Unknown |
Aureolysin | aur | Degradation of antimicrobial peptides | Unknown |
Secreted virulence factors required to breach the bloodstream | |||
α-Hemolysin | hla | Disruption of epithelial or endothelial surfaces | Reduced bacterial loads in organs |
Serine Aspartic Repeat protein C, D |
sdrC sdrD |
Members of the MSCRAMM, ligands unknown | Reduced bacterial loads in organs |
Secreted factors required for bacterial replication and persistence in abscesses | |||
Iron surface determinant A, B, C |
isdA isdB isdC |
Heme iron scavenging | Reduced bacterial loads |
Coagulases |
coa vwb |
Coagulation, agglutination | Reduced bacterial loads and numbers of abscesses |
Protein A (SpA) | spa | B cell superantigen activity that prevents humoral immune response | Reduced bacterial loads and numbers of abscesses in organs |
Lipoprotein diacyl-glyceride transferase | lgt | Lipidation of lipoproteins | Hypervirulence, abscesses devoid of immune cells due to loss of TLR2 ligands |
Extracellular adherence protein | eap | Blockade of neutrophil adherence to endothelia | Reduced bacterial loads in organs |
Extracellular fibrinogen–binding protein | efb | Blockade of C3 convertase; fibrinogen binding | Reduced bacterial loads in organs |
Phenol soluble modulins α3 | psmα3 | Generation of inflammatory signals for the recruitment of immune cells | Increased bacterial loads in organs |
Staphylococcal superantigen-like 5, 10 |
ssl5 ssl10 |
Impediment of neutrophil chemotaxis | Unknown |
Chemotaxis inhibitory protein | chips | Impediment of neutrophil chemotaxis | Unknown |
Formyl peptide receptor-like inhibitory proteins |
flipr flipr-like |
Impediment of neutrophil chemotaxis | Unknown |
The proposed function is derived from in vitro biochemical experimentation.
Virulence defect was tested as survival of bacteria in whole blood or enumeration of bacterial loads in animal organ tissues following infection.