title: Use of enzymes in typing group A beta-haemolytic streptococci.
abstract: A series of 698 strains of group A beta-haemolytic streptococci (GAS) isolated from children with streptococcal pyoderma was tested for production of serum opacity factor (OF) and nicotinamide adenine dinucleotide glycohydrolase (NADase). OF was produced by 37% of strains and 40% produced NADase. Classification based on various combinations of OF and NADase reactions showed that 58% belonged to enzyme group el and 34% to e2. Correlation with T and M types showed the possible use of this means of classification as an epidemiological marker for GAS. The specificity of such a system in the further classification of various T types of GAS in epidemiological studies, in the light of antigenic variation among M types, is described.
mesh_terms: D015373:Bacterial Typing Techniques / Q000379:methods; D002648:Child; D006801:Humans; D011711:Pyoderma / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000145:classification* / Q000201:enzymology