Metagenomics deals with the isolation of genetic material directly recovered from environmental samples. Metagenomics as an approach has emerged over the past two decades to elucidate a host of microbial communities inhabiting a specific niche with the goal of understanding their genetic diversity, population structure, and ecological role played by them. A number of new and novel molecules with significant functionalities and applications have been identified through this approach. In fact, many investigators are engaged in this field to unlock the untapped genetic resources with funding from governments sector. The sustainable economic future of modern industrialized societies requires the development of novel molecules, enzymes, processes, products, and applications. Metagenomics can also be applied to solve practical challenges in the field of medicine, agriculture, sustainability, and ecology. Metagenomics promises to provide new molecules and novel enzymes with diverse functions and enhanced features compared to the enzymes from the culturable microorganisms. Besides the application of metagenomics for unlocking novel biocatalysts from nature, it also has found applications in fields as diverse as bioremediation, personalized medicine, xenobiotic metabolism, and so forth. 1. Introduction The term metagenomics, the genomic analysis of a population of microorganisms, was coined by Handelsman et al. with a notion to analyse a collection of similar but not identical items, as in the statistical concept of meta-analysis [1]. The idea that the whole environmental microbiome can be explored and analysed together has revolutionized our understanding of the ecology around us. It has opened new horizons in the development of biotechnology based on the exploitation of uncultivated microbial species. The vast majority of microorganisms being unculturable [2], metagenomics has resulted in discoveries that remained hidden from the traditional culturing techniques. Though a multifaceted approach, the crux of applied metagenomics is to express recovered genes in a cultivable heterologous host. A booming area of biotechnology is the industrial use of microorganisms to produce antibiotics, enzymes, and other bioactive compounds. The demand for the commercial production of enzymes that are used in large-scale industrial processes is growing rapidly. The industrial applications of metagenomics include identification of novel biocatalysts, discovery of new antibiotics, personalized medicine, and bioremediation. In addition, biosurfactant producing bacteria have been
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