@article{mbs:/content/journal/micro/10.1099/00221287-128-8-1863, author = "Pandey, Narendra K. and Switzer, Robert L.", title = "Mutant Strains of Salmonella typhimurium with Defective Phosphoribosylpyrophosphate Synthetase Activity", journal= "Microbiology", year = "1982", volume = "128", number = "8", pages = "1863-1871", doi = "https://doi.org/10.1099/00221287-128-8-1863", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-128-8-1863", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = "mutant of Salmonella typhimurium with undetectable phosphoribosylpyrophosphate (PRPP) synthetase activity in vitro and abnormally low PRPP pools in vivo was identified by screening temperature-sensitive isolates by an autoradiographic procedure. The lack of PRPP synthetase activity in vitro and temperature-sensitive growth were shown to result from separate, but closely linked mutations mapping at 47 units on the Salmonella chromosome. Mutant cell extracts prepared by a variety of methods did not show any detectable PRPP synthetase activity, but material that was immunochemically cross-reactive with PRPP synthetase was detected by complement fixation analysis. A second mutant, isolated by localized mutagenesis, contained about half the PRPP synthetase and cross-reacting material of the parental strain.", }