Characterization of a suppressor mutation complementing an acid-sensitive mutation in Streptococcus mutans.

Maciej Lis; Howard K Kuramitsu

doi:10.1016/s0378-1097(03)00818-8

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Characterization of a suppressor mutation complementing an acid-sensitive mutation in Streptococcus mutans.

Maciej Lis·Howard K Kuramitsu

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Abstract

We isolated a spontaneous suppressor mutant complementing the acid-sensitive phenotype of Streptococcus mutans strain Tn-1, a mutant previously generated in this laboratory, defective in the activity of the dgk-encoded putative undecaprenol kinase. A relatively simple genetic method was developed to identify the suppressor mutation, based on selection for transformants containing two closely linked markers: a selectable allele of the unknown suppressor gene and an antibiotic resistance gene introduced on a suicide plasmid at random sites into the chromosome via homologous recombination. While we have not actually identified the original suppressor mutation, another mutated gene restoring acid resistance has been isolated, which suggests a possible mechanism of suppression.

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Acids Diacylglycerol Kinase Mutation Phenotype Phosphorylation Phosphotransferases (Alcohol Group Acceptor)Plasmids Streptococcus mutans Suppression, Genetic Journal Article Research Support, U.S. Gov't, P.H.S.

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Maciej Lis, Howard K Kuramitsu. 2003-12-12. Characterization of a suppressor mutation complementing an acid-sensitive mutation in Streptococcus mutans.. https://doi.org/10.1016/s0378-1097(03)00818-8

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