Identification of a new motif in family B DNA polymerases by mutational analyses of the bacteriophage t4 DNA polymerase.

ABSTRACT: Structure-based protein sequence alignments of family B DNA polymerases revealed a conserved motif that is formed from interacting residues between loops from the N-terminal and palm domains and between the N-terminal loop and a conserved proline residue. The importance of the motif for function of the bacteriophage T4 DNA polymerase was revealed by suppressor analysis. T4 DNA polymerases that form weak replicating complexes cannot replicate DNA when the dGTP pool is reduced. The conditional lethality provides the means to identify amino acid substitutions that restore replication activity under low-dGTP conditions either by correcting the defect produced by the first amino acid substitution or by generally increasing the stability of polymerase complexes; the second type are global suppre

SUBMITTER: Li V 

PROVIDER: S-EPMC3153374 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature