Cloning and complete sequence of the DNA polymerase-encoding gene (BstpolI) and characterisation of the Klenow-like fragment from Bacillus stearothermophilus.

A fragment of the DNA polymerase I-encoding gene (polI) from Bacillus stearothermophilus (Bst) was obtained by PCR. This was used as a probe to obtain a full-length gene from a Bst genomic DNA (gDNA) plasmid library. Comparison of the sequence to B. caldotenax (Bca) showed about 93% homology at the amino acid (aa) level. A Klenow-like (BstpolIk) clone was developed and the recombinant protein displayed DNA polymerase activity similar to the wild-type BstPolI enzyme.