Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India.
Department of Zoology, Deshbandhu College, Kalkaji, New Delhi, India.
Appl Microbiol Biotechnol. 2023 May;107(10):3273-3289. doi: 10.1007/s00253-023-12503-6. Epub 2023 Apr 13.
The hot spring microbiome is a complex assemblage of micro- and macro-organisms; however, the understanding and projection of enzymatic repertoire that access earth's integral ecosystem processes remains ambivalent. Here, the Khirganga hot spring characterized with white microbial mat and ions rich in sulfate, chlorine, sodium, and magnesium ions is investigated and displayed the examination of 41 high and medium qualified metagenome-assembled genomes (MAGs) belonged to at least 12 bacterial and 2 archaeal phyla which aids to drive sulfur, oxygen, iron, and nitrogen cycles with metabolic mechanisms involved in heavy metal tolerance. These MAGs possess over 1749 genes putatively involved in crucial metabolism of elements viz. nitrogen, phosphorus, and sulfur and 598 genes encoding enzymes for czc efflux system, chromium, arsenic, and copper heavy metals resistance. The MAGs also constitute 229 biosynthetic gene clusters classified abundantly as bacteriocins and terpenes. The metabolic roles possibly involved in altering linkages in nitrogen biogeochemical cycles and explored a discerned rate of carbon fixation exclusively in archaeal member Methanospirillum hungatei inhabited in microbial mat. Higher Pfam entropy scores of biogeochemical cycling in Proteobacteria members assuring their major contribution in assimilation of ammonia and sequestration of nitrate and sulfate components as electron acceptors. This study will readily improve the understanding of the composite relationship between bacterial species owning metal resistance genes (MRGs) and underline the exploration of adaptive mechanism of these MAGs in multi-metal contaminated environment. KEY POINTS: • Identification of 41 novel bacterial and archaeal species in habitats of hot spring • Genome-resolved metagenomics revealed MRGs (n = 598) against Cr, Co, Zn, Cd, As, and Cu • Highest entropies of N (0.48) and Fe (0.44) cycles were detected within the MAGs.
温泉微生物组是一个由微观和宏观生物组成的复杂集合体；然而，对于能够进入地球整体生态系统过程的酶谱的理解和预测仍然存在矛盾。在这里，我们研究了以白色微生物垫和富含硫酸盐、氯、钠和镁离子为特征的 Khirganga 温泉，并展示了对至少 12 个细菌和 2 个古菌门的 41 个高质量和中等质量的宏基因组组装基因组 (MAGs) 的检查，这些 MAGs有助于通过涉及重金属耐受的代谢机制驱动硫、氧、铁和氮循环。这些 MAGs 拥有超过 1749 个基因，推测这些基因参与了关键的元素代谢，如氮、磷和硫，以及 598 个基因编码用于 czc 外排系统、铬、砷和铜重金属抗性的酶。MAGs 还构成了 229 个生物合成基因簇，分为细菌素和萜烯。这些代谢作用可能涉及改变氮生物地球化学循环的联系，并在微生物垫中发现了独特的古菌 Methanospirillum hungatei 固碳率。在变形菌门成员中，生物地球化学循环的 Pfam 熵得分较高，这确保了它们在氨同化和硝酸盐和硫酸盐成分作为电子受体的隔离方面的主要贡献。这项研究将有助于更好地理解拥有金属抗性基因 (MRGs) 的细菌物种之间的复杂关系，并强调这些 MAGs 在多金属污染环境中的适应机制的探索。 要点： • 在温泉栖息地中鉴定出 41 种新型细菌和古菌 • 基因组解析宏基因组学揭示了针对 Cr、Co、Zn、Cd、As 和 Cu 的 MRGs（n=598） • 在 MAGs 中检测到 N（0.48）和 Fe（0.44）循环的最高熵值。
