title: Application of serum opacity factor in subtyping of group A streptococci & identification of new M-types.
abstract: Out of 742 isolates of group A streptococci (GAS), 34.0 per cent were positive for production of serum opacity factor (SOF). The T and M typability of these GAS strains was 93.3 and 10.8 per cent respectively. Clustering of the strains under the T patterns 5/12/27, 8/25/Imp. 19 and 3/13/B3264 and low M typability indicated the utility of SOF testing as an additional marker in epidemiological characterisation of GAS. SOF was further found to be useful in identification of new M type and simplified M typing by saving time, labour and sera.
authors.affiliation: Department of Microbiology, Lady Hardinge Medical College, New Delhi.
authors.forename: K
authors.initials: K
authors.lastname: Prakash
authors.forename: S
authors.initials: S
authors.lastname: Dutta
mesh_terms: D000942:Antigens, Bacterial / Q000032:analysis*; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000032:analysis*; D002352:Carrier Proteins; D006801:Humans; D010447:Peptide Hydrolases / Q000032:analysis*; D013297:Streptococcus pyogenes / Q000145:classification*
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; C021908:opacity factor; C014689:streptococcal M protein; D010447:Peptide Hydrolases