Molecular cloning and characterization of phosphoacetylglucosamine mutase from Bombyx mori

The present study conducted at Centre for Bioinformatics, Pondicherry University for a period of six months during the year 2016 explored the molecular and structural features of phosphoacetylglucosamine mutase from Bombyx mori, a crucial enzyme of chitin metabolic pathway. A 1647 bp long full-length cDNA was amplified, cloned and gene-expression profile was studied which inferred the crucial role of BmPAGM during larval molting. The ORF encoded a 548 amino acid long polypeptide with theoretical molecular mass of 59.859 kDa, pI of 5.65 and sequence similarity of >80% to other lepidopteran PAGMs. Sequence alignment and phylogenetic analysis of various PAGMs added an insight on their evolutionary relationship. The 3D structure of BmPAGM was predicted and refined by molecular dynamics simulations to study various structural features. The structure composed of four domains with a centrally located active site and magnesium ion coordinated to three aspartic acids of the metal binding loop. This study will be useful to scientific community working on chitin metabolizing enzymes.