Srivastava Ankita, Verma Digvijay
Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar University, Lucknow, India, 226025.
Environ Sci Pollut Res Int. 2023 Jan;30(1):752-772. doi: 10.1007/s11356-022-22198-3. Epub 2022 Jul 29.
Sediment provides a stagnant habitat to microbes that accumulate organic matter and other industrial pollutants from the upper layer of the water. The sediment of the Ganga River of India is overlooked for exploring the bacterial diversity despite their taxon richness over the water counterpart. To enrich the limited information on the bacterial diversity of the Ganga River sediment, the present study was planned that relies on amplicon-based bacterial diversity of the Ganga River sediment by using bacterial-specific 16S hypervariable region (V-V). The Illumina MiSeq2500 platform generated 1,769,226 raw reads from the metagenomes of various samples obtained from ten sites in five major cities of Uttar Pradesh and Uttarakhand regions traversing the Ganga River. Taxonomy level analysis assigned 58 phyla, 366 order, and 715 genera of bacterial type. The high values of various diversity indices (Chao1, Shannon, and Simpson) in Kanpur sediment indicate the high bacterial richness compared to the Rishikesh sediment. However, several other ecological parameters (Shannon index, Simpson index, enspie _vector, and Faith_pd) were comparatively higher in Rishikesh sediment which is a comparatively less disturbed region by human activities over the other sediments samples studied here. Ganga River sediment dominates with Gram-negative, chemo-heterotrophic, and aerobic bacteria that chiefly belong to Proteobacteria, Acidobacteria, Chloroflexi, and Bacteroidota. The abundance of Nitrospira, Hydrogenophaga, Thauera, Vicinamibacteraceae, and Latescibacterota in the Ganga River sediment could be considered as the ecological indicators that find a significant role in the degradation of xenobiotic compounds. The PICRUSt-based analysis showed that ~ 35% of genes were involved in benzoate and aminobenzoate degradation where a significant portion of genes belong to nitrotoluene degradation (14%). Thus, the study uncovers a new perspective in the lineage of bacterial communities and their functional characterization of the Ganga River sediment.
沉积物为微生物提供了一个停滞的栖息地,这些微生物会积累来自水表层的有机物质和其他工业污染物。尽管印度恒河沉积物中的分类单元丰富度高于水体,但在探索细菌多样性方面却被忽视了。为了丰富关于恒河沉积物细菌多样性的有限信息,本研究计划通过使用细菌特异性16S高变区(V-V),依赖基于扩增子的恒河沉积物细菌多样性研究。Illumina MiSeq2500平台从跨越恒河的北方邦和北阿坎德邦五个主要城市的十个地点采集的各种样本的宏基因组中生成了1,769,226条原始读数。分类水平分析确定了58个门、366个目和715个细菌属。坎普尔沉积物中各种多样性指数(Chao1、香农和辛普森)的高值表明,与瑞诗凯诗沉积物相比,其细菌丰富度更高。然而,瑞诗凯诗沉积物中的其他几个生态参数(香农指数、辛普森指数、enspie_vector和Faith_pd)相对较高,该地区相比此处研究的其他沉积物样本,受人类活动干扰较少。恒河沉积物中以革兰氏阴性、化学异养和好氧细菌为主,主要属于变形菌门、酸杆菌门、绿弯菌门和拟杆菌门。恒河沉积物中硝化螺旋菌属、嗜氢菌属、陶厄氏菌属、维西纳米杆菌科和隐秘杆菌门的丰度可被视为生态指标,它们在降解外源化合物中发挥着重要作用。基于PICRUSt的分析表明,约35%的基因参与苯甲酸和氨基苯甲酸的降解,其中很大一部分基因属于硝基甲苯降解(14%)。因此,该研究揭示了恒河沉积物细菌群落谱系及其功能特征的新视角。