The Degradation of Starch by Strains of Group A Streptococci having Related Antigens

Abstract

S7JMMAR.Y:Strains of Group A streptococci produced an extracellular carbohydrase which degraded starch. The enzyme in crude undialysed culture filtrates bore a general resemblance to pancreatic diastase. Amylolytic activity was decreased in environmental conditions which also affected streptococcal proteinase, namely in cultures grown at 2 8 O , in filtered broth, or after aerial mouse passage. Amylase production was associated with hyalmnidase production in strains having the type-specific M antigen 4, or the non-specific T antigen 4, whereas pmkinase-positive strains of the same p u p of closely related specific Types 4, %, 26, 28, 29, 46 were ususlly amylase-negative; but the association between production of any two of the three enzymes was not complete. Hyaluronidase-positive Type 22 strains did not produce amylase, and with two exceptions, a Type 2 strain and a strain serologically unidentified, other representative serological types were amylase-negative, though some strains degraded starch in growing cultures.The use of starch in fermentation studies of streptococci was suggested by Andrewes who compared endemic Australian strains with Griffith types, and found that stasch was fermented by strains serologically classified as Types 1, 2, 4, 9, 10 and 28. Maxted (personal communication), using starch plates, found that ability to split starch, though commonly shown by Type 4 strains, was infrequent in other endemic British strains examined at the Streptococcal Reference Laboratory. While studying strains isolated during a survey of hyaluronidase production Crowley (1944) observed that ability to split starch was displayed by Type 4 strains (T antigen, non-specific) with the greatest hyaluronidase activity. Both polysaccharidase activities were absent, however, in Type 4 strains which were strongly proteinase positive. In this connexion Dr S. D. Elliott (personal communication) observed that proteinase added to cultures suppressed hyaluronidase activity, and suggested that intermittent proteinase production might explain variable behaviour by hyaluronidasepositive strains. The experiments described in this paper were made to establish the incidence of amylolytic activity in relation to the antigenic components, to investigate the coincidence of different polysaccharidases elaborated by the same strains and to study the effect of proteinase on the carbohydrase activity of the strains, with reference to the occasional anomalous behaviour of streptococcal hyaluronidase which has been reported. MATERIAL AND METHODSSource of the strains. Hyaluronidase-producing strains were isolated during 1941-8 in a survey of hyaluronidase activity in endemic group A streptococci and subsequently preserved in the dried state. The Types were identified by slide

The Action of Streptococcal Amylase in relation to the Synthesis of an Amylosaccharide by Amylolytic Strains of Streptococcus pyogenes

“…The resemblance of streptococcal amylase to a-amylase was previously noted (Crowley, 1950(Crowley, , 1954. This paper describes a quantitative study of (1) a method of producing potent amylolytic cultures, (2) the amylase action, and (3) the production of a starchy cell substance by the same strains of group A streptococci.…”

Production of a bacteriocine-like substance by group-A streptococci of M-type 4 and T-pattern 4

“…Group-A streptococci of this serotype have previously been observed to have distinctive properties which tend to set them apart from other streptococci. They are said to be frequently associated with the development of acute glomerulonephritis (Stollerman, 1975) and scarlet fever (Lutticken et al, 1977) and also to produce large amounts of hyaluronidase (Gerlach & Kohler, 1972), amylase (Crowley, 1950) and intracellular starch (Crowley, 1959). Recently, Kohler and Prokop (1978) were able to demonstrate a relationship between the haptoglobin genotype of human serum and its capacity to agglutinate group-A streptococci carrying the T4/24 antigen.…”

Polysaccharidases of Group A Streptococci

“…Proteinase activity by strains of the T antigen groups 4, 24, 26,28,29 and 46 was associated with absence of polysaccharidase production (Crowley, 1950).…”

“…The inactivation of amylase by salicylates raises several problems. Heparin inactivates both hyaluronidase (McClean, 1942) and amylase (Crowley, 1950). Calcium ions activate amylase and the anticoagulant effect of heparin has been attributed (among other factors) to the binding of calcium.…”