The Locus PgaABCD of Acinetobacter junii Putatively Responsible for Poly-β-(1, 6)-N-Acetylglucosamine Biosynthesis Might Be Related to Biofilm Formation: A Computational Analysis

Poly-β-(1,6)-N-acetylglucosamine (PNAG), the chief mediator of intercellular adhesion in many bacteria, plays an important role in biofilm formation. The pgaABCD locus was recognized from the whole genome sequence of A. junii SH205. The enzyme glycosyltransferase, PgaC, catalyzes the production of PNAG with N-acetyl-D-glucosamine monomer. In this study, the possibility of PNAG biosynthesis in A. junii SH205 with its own PgaC was explored with the aid of bioinformatics. Multiple alignments of PgaC sequences of different bacteria were used to identify conserved amino acid residues that might be critical for the functioning of the protein. Three-dimensional model of A. junii SH205 PgaC was generated for spatial visualization of amino acid residues. The analyses have shown that the protein PgaC has five conserved amino acids, Asp140, Asp233, Gln269, Arg272 and Trp273, critical for the activity of enzyme. Interaction of UDP-N-acetylglucosamine within the conserved pocket of glycosyltransferase was explored from molecular docking studies.