A mutation, bsu, that suppresses temperature-sensitive dnaB function in Escherichia coli K12.

A mutation of Escherichia coli K12 that suppresses certain temperature-sensitive dnaB mutations was identified. The suppressor, named bsu maps very near the dnaG mutations. The bsu mutation in dnaB bacteria appears to be dominant over the wild-type allele, and suppresses specifically the temperature-sensitive dnaB mutations which are revertible phenotypically when salt is present. The observed specificity in suppression suggests that the product of bsu alone cannot substitute for the defective dnaB gene products. These findings suggest strongly that gene products of bsu and dnaB interact with each other in the process of DNA replication in E. coli.