Recombination in H1, the Gene Determining the Flagellar Antigen-i of Salmonella typhimurium; Mapping of H1 and fla Mutations

• Published in: Journal of general microbiology Vol. 58; no. 2; pp. 267 - 275
• Main Authors: JOYS, T. M, STOCKER, B. A. D
• Format: Journal Article
• Language: English
• Published: England Soc General Microbiol 01-10-1969
• Subjects: Antigens; Genes; Mutation; Recombination, Genetic; Salmonella Phages; Salmonella typhimurium; Transduction, Genetic
• ISSN: 0022-1287
• DOI: 10.1099/00221287-58-2-267

Guinness-Lister Research Unit, Lister Institute of Preventive Medicine, Chelsea Bridge Road, London, S. W. 1
ABSTRACT
SUMMARY: Five fla mutations of Salmonella typhimurium LT2 have been mapped by transduction. They were isolated from five motile ( fla + ) strains each with a different form of antigen- i , caused by mutation of H1 , the structural gene for phase-1 flagellin. H1 was cotransduced (frequency 0.1 to 0.5) with each of the fla mutations. Three-point crosses using a serological selection technique indicate the following order: fla -50- fla -58- fla -55- H1. The position of fla -52 was not discovered. If the fla complementation groups correspond to the fla genes their order is flaB-flaD-flaA-H1.
Of the five H1 mutations four (M5, M20, M11, M12) appear to be very closely linked. The fifth (M6) is outside this cluster. Transductants with functionally and antigenically normal antigen- i were obtained, at a very low frequency, in crosses between i -curly and fla strains: they are attributed to crossing over within H1 between the ‘curly’ mutation and the mutations causing alteration in serological character. Some earlier conclusions (Joys & Stocker, 1963) as to gene order, especially within H1 , now seem unjustified.
Present address: Department of Medical Microbiology, Stanford University School of Medicine, Stanford, California 94305, U.S.A.
* Present address: Department of Microbiology, University of Oregon Medical School, Portland, Oregon 97201, U.S.A.