Biphasic Modulation of Mouse Macrophage Cell Growth by the Salmonella choleraesuis Cytotoxin P56

• Main Authors: Kuo-Chieh Ho, Dai-Chang Kuo, Gan-Nan Chang
• Format: Article
• Language: English
• Published: National Taiwan University 2003-12-01
• Series: Taiwania
• Subjects: Salmonella choleraesuis; Secretory cytotoxin; Cytotoxic effect; Mitogenic effect
• Online Access: http://tai2.ntu.edu.tw/taiwania/abstract.php?type=abstract&id=18

P56, a cytotoxin with a molecular weight of 56 kDa and an isoelectric point of 6.2 was isolated and purified from the cell-free supernatant of Salmonella choleraesuis CH12440 culture. P56 was a secretory protein. It could be detected as early as 3 hr in the supernatant of bacterial culture, and the presence of calcium in the medium would increase the secretion by a factor of 3.2. P56 had dose-dependent effects on mouse macrophage cell line P388-D1 and mouse peritoneal macrophages: It caused death of both kinds of cells at high concentrations. In contrast, it had a mitogenic effect on the cells at lower doses. Western blot analysis showed that the antibody raised against P56 reacted to P56 and proteins of S. choleraesuis lysate. However, there was no cross-reaction between P56 and the antibody raised against the dead cells.