Metagenomic Analysis Reveals Correlation Between Microbiome Structure and Leonardite Characteristics from Kazakhstan Coal Deposits

Abstract

Coal microbial communities have not been well examined, despite their importance in the formation and maintenance of terrestrial ecosystems. Microorganisms are geographically versatile, exhibit wide morphological diversity and provide a rich platform for studying energy and carbon flows through different ecosystems. The coal characteristics, in turn, are important environmental factors that control the composition, structure and activity of terrestrial bio-communities through various endogenous physiological and biochemical processes. The total phylogenetic structure of prokaryotes is closely related to their functional diversity and, ultimately, to the variety of environmental conditions in oxidized coal (leonardite). Metagenomic studies in this area attempt to assess the relationship between the coal properties and its microbiome. The microbial community of the coal profiles, collected from various Kazakhstan coal deposits, have been studied in detail for the first time using high-throughput sequencing. As part of this study, a wide range of leonardites generated in various bioclimatic and geomorphological conditions are considered. A comprehensive characterization of the phylogenetic structure and diversity of coal was given on the basis of the 16S rDNA gene analysis. The revealed features of the prokaryotic composition can be used as bioindicators of the leonardite condition. In addition, metagenomic characteristics of coals of different origin can serve as valuable platform to assess the terrestrial ecosystem health.