Clonal relationships among naturally occurring nicotinamide-requiring Salmonella typhimurium

• Published in: Genetical Research Vol. 46; no. 3; pp. 241 - 250
• Main Authors: Barker, Ruth M., Yousuf, A. A.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.12.1985
• Subjects: Bacteriology; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Genetics; Microbiology; Niacinamide - metabolism; Salmonella Phages - genetics; Salmonella typhimurium; Salmonella typhimurium - genetics; Species Specificity; Transduction, Genetic; Resistance; Bacteria; Nicotinamide; Transduction; Mutation; Escherichieae; Salmonella typhimurium; Enterobacteriaceae; Genetic transfer
• ISSN: 0016-6723; 1469-5073
• DOI: 10.1017/S0016672300022746

Salmonella typhimurium strains of biotype 25x have been shown in transductional cross experiments to be clonal in the Nad character. The ancestral bacterium, probably of biotype 25a, mutated to a requirement for nicotinamide and subsequently diversified in phage type and secondary biotype characters. Such a sequence of events indicates interconversion among phage types 6, 16, 46, 49, 73, 76 and 135. Strains in biotypes 1x, 9ix, 17x, 17dx, 19dx and 25hix yielded Nad+ recombinants in interbiotype crosses, suggesting that each originated as an independent mutant line.