RT Journal Article SR Electronic(1) A1 Kok, Menno A1 Bühlmann, Elisabeth A1 Pechère, Jean-ClaudeYR 2001 T1 Salmonella typhimurium thyA mutants fail to grow intracellularly in vitro and are attenuated in mice JF Microbiology, VO 147 IS 3 SP 727 OP 733 DO https://doi.org/10.1099/00221287-147-3-727 PB Microbiology Society, SN 1465-2080, AB Salmonella typhimurium ATCC14028 readily multiplies in professional phagocytes in vitro and is highly virulent in mice. Mutants lacking thymidylate synthase activity (thyA) were isolated and shown to be strictly dependent on thymidine monophosphate precursors in the growth medium. The thyA mutants were found to be virtually incapable of intracellular growth and survival in vitro, both in macrophage-like cell line P338D1 and in the human epithelial cell line Hep-2, and their virulence was impaired in BALB/c mice. Intraperitoneal immunization of mice with two doses of live S. typhimurium thyA provided protection against a challenge with 103 times the 50% lethal dose of the virulent parent strain., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-147-3-727