title: Mutation preventing capsular polysaccharide synthesis in Escherichia coli K-12 and its effect on bacteriophage resistance.
abstract: A mutant strain of Escherichia coli K-12 was found in which spontaneous mutation to phage T7 resistance occurred at a very low frequency. T7 resistance in the parental strain from which this mutant was derived resulted from a mutation to excess capsular polysaccharide synthesis. The mutation preventing T7 resistance, non-9, inhibited capsule formation when transduced into capsulated strains. The non-9 mutation was cotransducible with his, the gene order in this region being non-9 his Su-1.
mesh_terms: D000327:Adsorption; D002874:Chromosome Mapping; D003090:Coliphages; D003429:Cross Reactions; D003470:Culture Media; D004926:Escherichia coli / Q000032:analysis / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects; D005827:Genetics, Microbial; D006146:Guanidines; D009153:Mutagens; D009154:Mutation; D009603:Nitroso Compounds; D009711:Nucleotides / Q000378:metabolism; D010429:Pentoses / Q000032:analysis; D011135:Polysaccharides, Bacterial / Q000032:analysis / Q000096:biosynthesis*; D011995:Recombination, Genetic; D014161:Transduction, Genetic; D014466:Ultraviolet Rays
chemical_list: D003470:Culture Media; D006146:Guanidines; D009153:Mutagens; D009603:Nitroso Compounds; D009711:Nucleotides; D010429:Pentoses; D011135:Polysaccharides, Bacterial