Chitin metabolism enhancement by β- <i>N</i> -acetyl-D-glucosaminyl-(1,4)-D-glucosamine in <i>Vibrio</i> is associated with chitin disaccharide transporter

Abstract In Vibrio parahaemolyticus RIMD2210633, chitin metabolism is enhanced by β-N-acetyl-D-glucosaminyl-(1,4)-D-glucosamin (GlcNAc-GlcN), which is produced from N,N’-diacetylchitobiose using chitin oligosaccharide deacetylase. However, GlcNAc-GlcN metabolism is not well understood. Vibrio bacteria have two types of disaccharide transport systems: the ABC transporter and the phosphotransferase system (PTS). The ABC transporter system is involved in the transcription of proteins related to metabolism. In this study, we clarified the mechanism by which GlcNAc-GlcN is transported into the cell and activates chitin metabolism. Using two types of Vibrio spp., in the presence or absence of chitin oligosaccharide deacetylase and PTS, we investigated the transcription of chitinases and transporters using real-time quantitative PCR. Furthermore, the utilization of disaccharides was investigated using bacterial proliferation. Our results suggested that GlcNAc-GlcN may act as a transcriptional signal via ABC transporter proteins but is translocated via PTS. These findings are expected to the study of the ecology of GlcNAc-GlcN-utilizing bacteria, about which little information is available.