Cloning and sequencing of lactase gene from Aspergillus candidus / 生物工程学报

ABSTRACT

Genomic DNA and cDNA sequences of lactase from Aspergillus candidus were cloned. Sequences analysis revealed that the genomic DNA was 3458 bp containing eight introns, cDNA was 3015 bp and encoding a polypeptide of 1005 amino acid residues. Signal peptide was 19 amino acid residues, eleven potential N-glycosylation sites were assumed. Comparing the gene cDNA and amino acid sequences with other lactase sequences from various sources, it showed a very low homology with most of other sequences. Although the gene had a higher homology to Aspergillus oryzae lactase sequence, characterization of both enzymes exhibited obvious difference. The gene from Aspergillus candidus was a promising new gene for food industry.