Genomic analysis of Tenacibaculum sp. IMCC1 reveals its genetic potential for chitin degradation

Chitin, one of the most abundant marine polysaccharides, plays a pivotal role in global carbon‑nitrogen cycles, and its degradation is mediated by marine chitinolytic microorganisms. The widely distributed genus Tenacibaculum is well known for its fish pathogenicity and its capacity to degrade diverse polysaccharides; however, its potential for chitin degradation remains poorly characterized. Here, we isolated a novel bacterium, Tenacibaculum sp. IMCC1, from the Philippine Sea, sharing 98% 16S rRNA gene similarity with Tenacibaculum mesophilum. Genome sequencing yielded a 3,357,366 bp circular chromosome (G + C content 31.73%) containing 3124 protein-coding genes, 55 tRNAs, and 5 rRNA operons (no plasmids). CAZy annotation identified 126 carbohydrate-active enzymes (CAZymes). Genome analysis further revealed a putative chitin degradation pathway, encompassing extracellular depolymerization of chitin into chitooligosaccharides, their subsequent hydrolysis into N-acetylglucosamine (GlcNAc) and glucosamine (GlcN), transport into the cytoplasm, and downstream metabolism to UDP-GlcNAc, a key precursor for peptidoglycan biosynthesis. Together, these results predict the chitin-degrading potential of Tenacibaculum sp. IMCC1, expanding the functional repertoire of marine chitinolytic bacteria and providing genetic resources for ecological studies and chitin biotechnological valorization.