Abstract
Protein A extracellularly produced by UV2 (a mutant of Staphylococcal aureus Cowan I) in some cultivation conditions was analyzed with two dimensional electrophoresis and immunoblotting. Three major proteins (MW 47Kd, pI 5.2; MW 50Kd, pI 5.1; MW 51Kd, pI 5.0) were indicated on the electropherogram of the fluid of conventional cultivation at 37°C, and these proteins were identified with protein A. The same protein A was observed in the cultivation fluid using cellophane bag at 25°C, but the fluid was characterized by the presence of low molecular weight protein A in the range of MW 18Kd-49Kd and pI 4.2-5.8 and many non-protein A protein. On the other hand, in the fluid of the cellophane bag cultivation at 37°C, there only observed a lot of low molecular weight protein A ranging between MW 35Kd-13Kd and pI 4.5-6.5 and considerable amount of non-protein A proteins that were never found in the conventional cultivation fluid.
