Lian Xu-Dong, Guan Yong, Jiang Yue, Kwak Dong-Heui, Lee Mi-Kyung, Li Zhun
Biological Resource Center, Korean Collection for Type Cultures (KCTC), Korea Research Institute of Bioscience and Biotechnology, Jeongeup, 56212, Republic of Korea.
Department of bio-convergence science, Jeonbuk National University, jeonju, 54896, Republic of Korea.
Sci Rep. 2025 Jan 28;15(1):3494. doi: 10.1038/s41598-025-87876-x.
Polysaccharides are recognized for their extensive biological functions, holding significant promise for applications in both medicine and food industries. However, their utilization is frequently constrained by challenges such as high molecular weights and indistinct sugar chain structures. Recently, two novel bacterial strains, N6 and J3, were isolated from the Nakdong River in Korea. These strains, which belong to the phylum Bacteroidota, are Gram-stain-negative, non-motile, aerobic, rod-shaped bacteria and have shown polysaccharide-degrading capabilities. Through comprehensive analyses, including 16S rRNA gene sequencing, whole-genome sequencing, and detailed morphological, physiological, and chemotaxonomic characterizations, these strains have been identified as new species within the genus Flavobacterium. KEGG pathway analysis further confirmed their robust capabilities for carbohydrate utilization. Additional investigations using the dbCAN and dbCAN-PUL databases identified the presence of carbohydrate-hydrolyzing enzymes (CAZymes) and polysaccharide utilization loci (PULs) within these strains, suggesting their potential to degrade various polysaccharides. Subsequent in vitro growth experiments demonstrated that strains N6 and J3 can degrade chitin, β-glucan, κ-carrageenan, and cellulose. Given their diverse polysaccharide degradation abilities, these strains are formally proposed to be named Flavobacterium polysaccharolyticum sp. nov. and Flavobacterium aureirubrum sp. nov. The type strains are designated as N6 (= KCTC 102173 = GDMCC 1.4609) and J3 (= KCTC 102172 = GDMCC 1.4608), respectively.
多糖因其广泛的生物学功能而受到认可，在医学和食品工业应用中具有巨大潜力。然而，它们的利用常常受到诸如高分子量和糖链结构不清晰等挑战的限制。最近，从韩国洛东江分离出了两株新型细菌菌株N6和J3。这些菌株属于拟杆菌门，是革兰氏阴性、无运动性、需氧的杆状细菌，并已显示出多糖降解能力。通过包括16S rRNA基因测序、全基因组测序以及详细的形态学、生理学和化学分类学特征分析在内的综合分析，这些菌株已被鉴定为黄杆菌属内的新物种。KEGG通路分析进一步证实了它们强大的碳水化合物利用能力。使用dbCAN和dbCAN-PUL数据库进行的进一步研究确定这些菌株中存在碳水化合物水解酶（CAZymes）和多糖利用位点（PULs），表明它们具有降解各种多糖的潜力。随后的体外生长实验表明，菌株N6和J3可以降解几丁质、β-葡聚糖、κ-卡拉胶和纤维素。鉴于它们多样的多糖降解能力，正式提议将这些菌株命名为解多糖黄杆菌新种（Flavobacterium polysaccharolyticum sp. nov.）和金黄黄杆菌新种（Flavobacterium aureirubrum sp. nov.）。模式菌株分别指定为N6（=KCTC 102173 = GDMCC 1.4609）和J3（=KCTC 102172 = GDMCC 1.4608）。
