Cloning of Endoglucanase I Gene from Trichoderma longi-brachiatum and Its Expression in Pichia pastoris / 微生物学通报

ABSTRACT

A cellulase high-yield strain was identified and named as Trichoderma longibrachiatum SSL by ITS sequence identification. The endoglucanase1 gene (eg1) encoding endo-l,4-?-D-glucanase I was ampli-fied by RT-PCR method, which including 1386 bp and encoding 461 amino acid. Sequence analysis showed that This gene has a more 90% homology with the T. longibrachiatum eg1 gene. The eg1 gene encoding the mature peptide was inserted into the Pichia pastoris expression vector pPIC9K, which resulted in construc-tion of the recombinant expression plasmid, pPIC9k-eg1. The pPIC9k-eg1 was then introduced into the host Pichia pastoris GS115. After the induction of methanol, extracellular recombinant endoglucanase I from the supernatant of the recombinant Pichia pastoris strain reached 73 U/mL. A clear strengthening of the protein bands, whose molecular weight is about 58 kD, appeared in the SDS-PAGE.