The marine microbiome is a complex and least-understood habitat, which play a significant role in global biogeochemical cycles. The present study reported the culture-independent assessment of microbial diversity from the Arabian Sea (AS) sediments (from Gujarat to Malabar; at 30 m depth) by using metagenome sequence analysis. Our results elucidated that bacterial communities in the Malabar coastal region are highly diverse than the Gujarat coast. Moreover, Statistical analysis (Spearman rank correlation) showed a significant correlation co-efficient value (r = P < 0.001) between microbial communities and physicochemical parameters (salinity and dissolved oxygen) in the water column. A total of 39 bacterial phyla were recorded from the eastern side of AS, of which six phyla Proteobacteria, Bacteroidetes, Actinobacteria, Cyanobacteria, Firmicutes, and Planctomycetes were found to be the most dominant group. The most dominant genus from Valapad region (Malabar Coast) was found to be Halomonas sp., while other regions were dominated with Psychrobacter pulmonis. The subsequent Principal Coordinate Analysis (PCoA) showed 99.53% variance, which suggests that, highly distinct microbial communities at Valapad (Malabar Coast) sampling location than other sites. Moreover, the microbial metabolic activity analysis revealed the important functions of microbial communities in the AS are hydrocarbon degradation, polymer degradation, nutrient oxidation and sulphate reduction (biodegradation process). Further extended studies are needed to be carried out for better understanding the functional diversity of microbial communities from the marine sediments.

海洋微生物组是一个复杂且鲜为人知的栖息地，在全球生物地球化学循环中起着重要作用。本研究报告了通过使用元基因组序列分析，对阿拉伯海（AS）沉积物（从古吉拉特邦到马拉巴尔；深30 m）的微生物多样性进行非培养性评估。我们的研究结果表明，马拉巴尔沿海地区的细菌群落比古吉拉特邦海岸的细菌群落高度多样化。此外，统计分析（Spearman等级相关性）显示水柱中微生物群落与理化参数（盐度和溶解氧）之间具有显着的相关系数值（r = P <0.001）。在AS的东侧总共记录了39个细菌门，其中6个门是Proteobacteria，Bacteroidetes，放线菌，蓝细菌，菌毛和菌种被发现是最主要的群体。从Valapad区域（马拉巴海岸）最优势属被认为是盐单胞菌属，而其他地区用为主的嗜冷pulmonis。随后的主坐标分析（PCoA）显示99.53％的差异，这表明与其他站点相比，Valapad（马拉巴尔海岸）采样地点的微生物群落高度不同。此外，微生物代谢活性分析表明，AS中微生物群落的重要功能是烃降解，聚合物降解，营养物氧化和硫酸盐还原（生物降解过程）。为了更好地理解海洋沉积物中微生物群落的功能多样性，需要进行进一步的研究。