Isolation, sequencing and overexpression of the gene encoding theθsubunit of DNA polymerase III holoenzyme

Abstract
The gene encoding the θ subunit of DNA polymerase III hoioenzyme, designated holE, was isolated using a strategy in which peptide sequence was used to derive a DNA hybridization probe. Sequencing of the gene, which maps to 41.43 centisomes of the chromosome, revealed a 76-codon open reading frame predicted to produce a protein of 8,846 Da. When piaced in a tac promoter expression vector, the open reading frame directed expression of a protein, that comigrated with authentic θ subunit from purified hoioenzyme, to 6% of total soluble protein.