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.
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