Department of Biotechnology, Bioengineering and Biochemistry of the National Research Mordovia State University, Saransk, Russia.
N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia.
PLoS One. 2021 Jul 6;16(7):e0253482. doi: 10.1371/journal.pone.0253482. eCollection 2021.
Paenibacillus spp. exopolysaccharides (EPSs) have become a growing interest recently as a source of biomaterials. In this study, we characterized Paenibacillus polymyxa 2020 strain, which produces a large quantity of EPS (up to 68 g/L),and was isolated from wasp honeycombs. Here we report its complete genome sequence and full methylome analysis detected by Pacific Biosciences SMRT sequencing. Moreover, bioinformatic analysis identified a putative levan synthetic operon. SacC and sacB genes have been cloned and their products identified as glycoside hydrolase and levansucrase respectively. The Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectra demonstrated that the EPS is a linear β-(2→6)-linked fructan (levan). The structure and properties of levan polymer produced from sucrose and molasses were analyzed by FT-IR, NMR, scanning electron microscopy (SEM), high performance size exclusion chromatography (HPSEC), thermogravimetric analysis (TGA), cytotoxicity tests and showed low toxicity and high biocompatibility. Thus, P. polymyxa 2020 could be an exceptional cost-effective source for the industrial production of levan-type EPSs and to obtain functional biomaterials based on it for a broad range of applications, including bioengineering.
蜂房被孢霉 2020 菌株产生大量胞外多糖（EPS），可达 68g/L，该菌株从胡蜂巢中分离得到，我们对其全基因组序列和通过 Pacific Biosciences SMRT 测序检测到的甲基组进行了全面分析。此外，生物信息学分析鉴定了一个推定的蔗糖果聚糖合成操纵子。克隆了 sacC 和 sacB 基因，并鉴定其产物分别为糖苷水解酶和蔗糖果聚糖酶。傅里叶变换红外（FT-IR）和核磁共振（NMR）谱表明，EPS 是一种线性β-（2→6）-连接的果糖（蔗果聚糖）。通过傅里叶变换红外（FT-IR）、核磁共振（NMR）、扫描电子显微镜（SEM）、高效体积排阻色谱（HPSEC）、热重分析（TGA）、细胞毒性试验对由蔗糖和糖蜜生产的蔗果聚糖聚合物的结构和性能进行了分析，结果表明该聚合物具有低毒性和高生物相容性。因此，P. polymyxa 2020 可以作为一种具有成本效益的 EPS 工业生产的特殊来源，并获得基于该 EPS 的功能性生物材料，广泛应用于包括生物工程在内的多个领域。
