Isolation and the 5'-end nucleotide sequence of Bacillus licheniformis alpha-amylase gene

Abstract

We have isolated and determined the 5′-end nucleotide sequence of the α-amylase gene from Bacillus licheniformis ATCC 14580. The α-amylase produced by this strain is thermostable and of liquefying type. The gene was originally cloned in a bacteriophage λ 1059 vector. A subclone containing a 5.3 × 10³-base insert in pBR 322 was further characterized. The nucleotide sequence coding for the 5′ end of the structural gene together with the sequence coding for the upstream control regions was determined. The deduced N-terminal amino acid sequence was identical with the previously published amino acid seequence of B. licheniformisα-amylase. There was also very strong homology to the N-terminal sequence of Bacillus amyloliquefaciensα-amylase. The M_r of the thermostable α-amylase, as determined in vitro in a cell-free transcription/translation system of Escherichia coli, was about 55000.