BIOSYNTHESIS AND PURIFICATION OF V AND W ANTIGEN IN PASTEURELLA PESTIS
ARMY BIOLOGICAL LABS FREDERICK MD
Pagination or Media Count:
The separation and purification of V and W antigens is described. The methods that gave the best results were 1 The precipitation of both antigens from the supernatant fluid of a 36C-grown culture of strain M23 by use of ammonium sultate. 2 Chromatography on DEAE-cellulose. V antigen was eluted with 0.1 M NaCl and W antigen with 0.5 M NaCl. Recycling on DEAE-cellulose resulted in a sample containing approximately 20 units of V antigenmg of protein 100-fold purification and no W antigen, and a sample containing 600 units of W antigenmg of protein 1000-fold purificationand no V antigen. V antigen is a protein with a molecular weight of 90,000 and W antigen is a lipoprotein with a molecular weight of 145,000. Both antigens were stable at 60C, but not at 80C, for 30 min. W antigen, but not V, was lost upon extensive dialysis against distilled water, or pervaporation. Both antigens were reduced in titer by prolonged storage at 5C or by lyophilization, but not by storage at -20C. Based on the use of rabbit antisera containing only V antibody or only W antibody, the conclusion was drawn that V antibody, but not W antibody, can protect mice against plague.