Factors Influencing the in vitro Production of Staphylococcal Coagulase

Abstract

SUMMARY: The amount of coagulase formed in vitro by coagulase-positive staphylococci depends on: the age of the bacterial cells, coagulase being produced only during the latter part of the lag-phase of growth; the period of incubation of the bacterial cells under ideal conditions, the optimum period depending upon the age of the cells when incubation starts; the initial concentration of bacteria. It also depends on the presence in the medium of a fermentable sugar and a factor found in brain-heart infusion and partially replaceable by peptone; the salt concentration in the medium; the initial pH value of the medium; the temperature of incubation: and upon substances present in rabbit serum and, to a lesser extent, horse serum, human serum and egg yolk, egg white and commercial nucleic acid not showing this effect. The activity of rabbit serum is destroyed by treatment with pepsin. Provided that the requisite conditions are met, cell-free coagulase which clots rabbit plasma within a few minutes, can be prepared in less than one hour.Since the demonstration that coagulase is an important factor in determining the pathogenicity of staphylococci, many papers on this substance have appeared (e.g. Christie

A Study of the Antigenic Specificity of Staphylococcal Coagulase in Relation to Bacteriophage Group

“…With the supernatant fluids, further elaboration of coagulase by remaining bacteria was prevented by adding sodium thiomersalate to give a final concentration of 1/10,000 (Davies, 1951 and strain Newman, phage type 7/47/53/54/73/75/77 (group 111). Later one strain each of phage types 3A and 42E were also used.…”

“…Barber and P . Wildy depends upon the fact that coagulase is released by nearly all strains of Staphylococcus aureus in the presence of albumin (Davies, 1951 ;Duthie, 1954). For large-scale preparations, strains were inoculated into a number of 8 oz.…”

Significance of Staphylocoagulase in Food Microbiology: A Review

“…Serum albumin h a s been responsible for enhancing staphylocoagulase elaboration by 10-fold or more (Davis 1951;Altenbern 1966). Increased coagulase production was also reported with culture shaking (Fahlberg a n d Martson 1960; Haughton a n d Duthie 1959; Stutzenberger and S a n Clemente 1968; Tager 1948).…”

Staphylocoagulase *

“…Although the cellular precursor of coagulase is unknown and the biosynthetic pathways leading to its formation not established, studies have been continued to define the factors and mechanisms involved in its elaboration by the staphylococci. In an earlier report, Davies reached the conclusion that coagulase is elaborated during the latter part of the log phase of growth, and noted that when a pepsin-sensitive factor present in rabbit and other sera, and in egg yolk, was added a t that time, an explosive release of coagulase may result (Davies, 1951). Duthie made the interesting observation that Davies' findings were reproducible with some staphylococcal strains, but not with others (Duthie, 19546).…”