Expression of the chitinase gene from Trichoderma aureoviride in Saccharomyces cerevisiae

Chitinase gene ech42 was obtained from Trichoderma aureoviride M and amplified by PCR. The isolated DNA of ech42 was then sequenced. The results showed that the open reading frame of ech42 was 1,447 bp long, encoding 421 amino acids. Three introns were found in the sequence. The cloning vector pMD18-T and an E. coli DH5α host were used to yield clones as E. coli DH5α/ech42. The ech42 gene was integrated into the genomic DNA of pYES2 by insertion into a single site for recombination, yielding the recombinant pYES2/ech42. Chitinase expressed by pYES2/ech42 was induced by galactose (maximal activity 0.50 units ml⁻¹) and was produced in fermentation liquid cultured for 36 h.