fcsA29 Mutation is an Allele of polA Gene of Escherichia coli

Abstract

  The cold-sensitive fcsA29 mutation of Escherichia coli was found to be a new type of cold-sensitive allele of the polA gene encoding DNA polymerase I, caused by an Asp(116)→Asn change in the 5′→3′ exonuclease domain. The fcsA29 mutant showed typical polA mutant phenotypes such as UV sensitivity and unacceptability of recA mutation. Cold-sensitive growth of the mutant was suppressed by introduction of a sulA mutation, indicating that cell filamentation was due to the SOS response.