Identification and Bioinformatics Analysis of Cysteine Synthase from the Filamentous Fungus, Monascus purpureus

Abstract

A gene encoding a putative cysteine synthase was obtained by screening Monascus purpureus cDNA library. Bioinformatics analysis showed that this protein has Rhodanese Homology Domain in C-terminal, and Pyridoxal-phosphate dependent enzyme domain in N-terminal, and CBS-like structure. The deduced cysteine synthase protein of M. purpureus contained 517 amino acid, with molecular mass of 57,044Da. Sequence alignment analysis revealed that M. purpureus deduced cysteine synthase was closely related to cysteine synthase from Aspergillus, Ajellomyces and Paracoccidioides, and highly homologous to aforementioned and other known cysteine synthase. The structural model of the deduced cysteine synthase closely match the template with 100% confidence and 20-30% identity. The consistency of the comparison results of the primary structure, secondary structure and tertiary structure suggests that the dedued protein may well be cysteine synthase.