DEMONSTRATION OF A RECEPTOR FOR MOUSE AND HUMAN SERUM ALBUMIN IN STREPTOCOCCUS PYOGENES

Abstract

Demonstration of a receptor for mouse and human serum albumin. Acta path. microbiol. immunol. scand. Sect. B, 91: 373-382, 1983. A new type of surface receptor for serum albumin was detected in strains of Streptococcus pyogenes (group A). This receptor. called type e. was different from albumin receptors in other streptococcal species. Only mouse and human serum albumin was bound to the receptor. The albumin-binding capacity was high: 2 x lo8 bacterial organisms bound I I pg of mouse albumin. The receptor was stable even when treated at 100 OC for 5 min. Binding of albumin was not mediated by lipoteichoic acid (LTA) because of lack of correlation to surface LTA, restricted albumin reactivity. and positive binding in presence of 2% Tween 20. Presence of albumin receptor type e correlated to presence of M-protein as measured by growth in the bactericidal test. All 51 M-protein positive group A streptococcal strains tested could bind mouse albumin whereas only 3 out of 8 M-protein negative strains showed positive binding (P<O.OOI). The sensitivity to trypsin digestion suggests that the albumin receptor is of protein nature or mediated by a protein.

Binding of Aggregated Human Serum Albumin to M12 And Some Other Types of Group A Streptococci

“…The binding of HSA to streptococci was increased three-to four-fold by aggregation, as shown by gel filtration of glutaraldehyde-treated HSA. However, the inhibition by untreated HSA showed that the binding of a*HSA was mediated by sites identical with those binding untreated albumin, recently described by Widebdck et al (23). These authors found group A streptococci to interact with murine serum albumin, and to a lesser degree with HSA.…”

Determination of the mimic epitope of the M-like protein adhesin in swine Streptococcus equi subsp. zooepidemicus

“…Similar to other streptococcal species, S . zooepidemicus binds to a number of host proteins, including immunoglobulin G [ 11 ], serum albumin [ 12 ], fibronectin, collagen [ 13 ], and α-macro-globulin [ 14 ] through cell surface components. These host-parasite recognition components may function as virulence factors by acting as adhesions or antiopsonins.…”