A novel mutation spatially remote from the G-domain in IF2 affects the cold stress adaptation of Escherichia coli.
In this paper, we describe a new mutation, gicD1, that gives a cold-sensitive phenotype in bacterial cell growth. Complementation analysis showed gicD1 to be allelic to infB. We identify gicD1 to be a valine to isoleucine substitution in initiation factor-2 (IF2) of a residue that seems to be well conserved in eubacterial IF2 proteins. This mutation lies in a region distant from the G-domain to which all earlier reported cold-sensitive mutations cluster. We describe a novel phenotype of the mutant that is suppression of rpsL31-mediated streptomycin resistance in cold. We provide evidence that mutant IF2 specifically interacts with rpsL31 in cold, leading to a bacteriostatic effect on host cells.
Rath
Devashish
D
Molecular Biology Division, Bhabha Atomic Research Center, Trombay, Mumbai 400 085, India. devrath@barc.gov.in
Mangoli
Suhas H
SH
Mahajan
Suresh K
SK
Jawali
Narendra
N
D019943:Amino Acid Substitution / Q000235:genetics; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003080:Cold Temperature; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D029968:Escherichia coli Proteins; D005816:Genetic Complementation Test; D020125:Mutation, Missense; D039881:Prokaryotic Initiation Factor-2 / Q000235:genetics / Q000502:physiology*; D025941:Protein Interaction Mapping; D012269:Ribosomal Proteins / Q000235:genetics; D013307:Streptomycin / Q000494:pharmacology; D013312:Stress, Physiological; D013489:Suppression, Genetic
D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; D039881:Prokaryotic Initiation Factor-2; D012269:Ribosomal Proteins; C506766:RpsL protein, E coli; D013307:Streptomycin