Department of Biochemistry and Molecular Biology, University of Belgrade - Faculty of Biology, Belgrade, Serbia.
Ras Al Khaimah Municipality Department, Director Environment Laboratories, Dubai, United Arab Emirates.
PLoS One. 2021 Nov 3;16(11):e0259465. doi: 10.1371/journal.pone.0259465. eCollection 2021.
Curtobacterium sp. GD1 was isolated from leaves of conventionally grown soybean in Brazil. It was noteworthy that among all bacteria previously isolated from the same origin, only Curtobacterium sp. GD1 showed a strong chitinase activity. The enzyme was secreted and its production was induced by the presence of colloidal chitin in the medium. The chitinase was partially purified and characterized: molecular weight was approximately 37 kDa and specific activity 90.8 U/mg. Furthermore, Curtobacterium sp. GD1 genome was sequenced and analyzed. Our isolate formed a phylogenetic cluster with four other Curtobacterium spp. strains, with ANIb/ANIm ≥ 98%, representing a new, still non described Curtobacterium species. The circular genome visualization and comparison of genome sequences of strains forming new cluster indicated that most regions within their genomes were highly conserved. The gene associated with chitinase production was identified and the distribution pattern of glycosyl hydrolases genes was assessed. Also, genes associated with catabolism of structural carbohydrates such as oligosaccharides, mixed polysaccharides, plant and animal polysaccharides, as well as genes or gene clusters associated with resistance to antibiotics, toxic compounds and auxin biosynthesis subsystem products were identified. The abundance of putative glycosyl hydrolases in the genome of Curtobacterium sp. GD1 suggests that it has the tools for the hydrolysis of different polysaccharides. Therefore, Curtobacterium sp. GD1 isolated from soybean might be a bioremediator, biocontrol agent, an elicitor of the plant defense responses or simply degrader.
短稳杆菌 GD1 从巴西常规种植的大豆叶片中分离得到。值得注意的是，在所有从同一来源分离的细菌中，只有短稳杆菌 GD1 表现出强烈的几丁质酶活性。该酶是分泌性的，其产生受到培养基中胶体几丁质的诱导。该几丁质酶被部分纯化并进行了表征：分子量约为 37 kDa，比活 90.8 U/mg。此外，还对短稳杆菌 GD1 基因组进行了测序和分析。我们的分离株与其他 4 株短稳杆菌菌株形成了一个系统发育聚类，ANIb/ANI m≥98%，代表了一个新的、尚未描述的短稳杆菌种。新聚类菌株的环状基因组可视化和基因组序列比较表明，它们基因组中的大多数区域高度保守。鉴定了与几丁质酶产生相关的基因，并评估了糖苷水解酶基因的分布模式。此外，还鉴定了与结构性碳水化合物（如寡糖、混合多糖、植物和动物多糖）代谢相关的基因，以及与抗生素、有毒化合物和生长素生物合成亚系产物抗性相关的基因或基因簇。短稳杆菌 GD1 基因组中假定的糖苷水解酶的丰度表明，它具有水解不同多糖的工具。因此，从大豆中分离得到的短稳杆菌 GD1 可能是一种生物修复剂、生物防治剂、植物防御反应的诱导剂或简单的降解剂。
