Molecular cloning of the gene for microbial transglutaminase from Streptoverticillium and its expression in Streptomyces lividans.

The microbial transglutaminase (TGase)-producing strains S-8112 [Agric. Biol. Chem., 53, 2613-2617 (1989)] was identified as a variant of Streptoverticillium mobaraense. We amplified a partial gene fragment by polymerase chain reaction (PCR) using oligonucleotides synthesized from the amino acid sequence of TGase, and cloned the gene for TGase using the PCR amplified fragment as a probe. The gene encoded a precursor of TGase consisting of 406 amino acid residues, which comprised the prepro region of 75 amino acid residues and the mature region of 331 amino acid residues. We expressed the TGase gene in Streptomyces lividans under a tyrosinase promoter, and found an active and mature recombinant enzyme, indicating the processing of the gene product.