β-N-Acetylglucosaminidase MthNAG from Myceliophthora thermophila C1, a thermostable enzyme for production of N-acetylglucosamine from chitin.

Thermostable enzymes are a promising alternative for chemical catalysts currently used for the production of N-acetylglucosamine (GlcNAc) from chitin. In this study, a novel thermostable β-N-acetylglucosaminidase MthNAG was cloned and purified from the thermophilic fungus Myceliophthora thermophila C1. MthNAG is a protein with a molecular weight of 71 kDa as determined with MALDI-TOF-MS.

Water-soluble chitosan derivatives and pH-responsive hydrogels by selective C-6 oxidation mediated by TEMPO-laccase redox system.

Chitosan is a polysaccharide with recognized antioxidant, antimicrobial and wound healing activities. However, this polymer is soluble only in dilute acidic solutions, which restricts much of its applications. A usual strategy for improving the functionality of polysaccharides is the selective oxidation mediated by 2,2,6,6-tetra-methyl-1-piperidinidyloxy (TEMPO) using laccase as a co-oxidant.

Chitinase Chi1 from Myceliophthora thermophila C1, a Thermostable Enzyme for Chitin and Chitosan Depolymerization.

A thermostable Chitinase Chi1 from Myceliophthora thermophila C1 was homologously produced and characterized. Chitinase Chi1 shows high thermostability at 40 °C (>140 h 90% activity), 50 °C (>168 h 90% activity), and 55 °C (half-life 48 h). Chitinase Chi1 has broad substrate specificity and converts chitin, chitosan, modified chitosan, and chitin oligosaccharides.