Coagulase production was investigated for 23 strains of Staphylococcus aureus. The coagulase from seven of these strains was purified and subjected to electrophoresis.
The dialyzable fraction of heart infusion broth was the growth medium. Coagulase was harvested from 5 hr shake cultures incubated at 37 c.
A series of dialysis steps lasting 24 hr at a temperature of 2 C were used to purify the different coagulases. The crude coagulase was first separated from the growth medium by dialysis against deionized water. The coagulase was next precipitated by dialysis against a £H 3.8 acetate buffer which had an ionic strength of 0.1. This was followed by another precipitation in a £H 5.2 acetate buffer with an ionic strength of 0.05. The remaining impurities were precipitated by dialysis against a £H 6.1 phosphate buffer with an ionic strength of 0.1. The three preceding buffers were prepared in deionized water containing 10% ethanol by volume. The final preparation was dialyzed against a EH 8.6 barbital buffer with an ionic strength of 0.075.
The seven purified coagulases were characterized by cellulose acetate electrophoresis. ·ach coagulase was electrophoresed for 110 min at 1.5 ma/cm strip length in a £H 8.6 barbital buffer having an ionic strength of 0.075. One of each set of electropherograms was stained with either Ponceau Sor Nigrosin and a duplicate was placed on fibrinogen agar to determine whether the stained bands represented active coagulase. Active coagulase produced precipitation bands in the agar. A total of 14 bands were demonstrated for the seven coagulases. Most of the purified coagulases were separated into several electrophoretically distinct forms. It was suggested that coagulase is an isoenzyme.
Level of Degree
UNM Biology Department
First Committee Member (Chair)
James S. Booth
Second Committee Member
Third Committee Member
John W. Beakley
Hill, John Elliott. "Variations In The Electrophoretic Mobility Of Purified Staphylocoagulase." (1970). https://digitalrepository.unm.edu/biol_etds/460