The main purpose of Master's thesis was to confirm the existence of metagenome-derived Prevotella species of rumen ecosystems from Scotland (Stewart et al., 2019), which is speculated to be fulfilled with the isolation of one such specimen. At the same time, we managed to cultivate strains of at least five new Prevotella species. Comparison of Stewart metagenomes and cultivated isolates of Prevotella revealed a distinctive deviation with metagenome-derived species showing absence of multiple core genome genes needed for MLSA analysis. Moreover, many had high numbers of CAZY enzymes and genome sizes. The majority of MAG fall into a category of medium quality drafts, which are discouraged from using in phylogenetic studies. According to TETRA and ANIb, Stewart metagenomes represent 161 species within Prevotellaceae family, however we have presumably isolated only one of them. Congruency of genes coding for ribosomal proteins, conserved in cultivated isolates of Prevotella is missing in most metagenome-derived species. In our judgement, complete analysis from raw reads obtained in Stewart et al. (2019) should be repeated, this time with multiple algorithm approach to assembly and binning of reads in order to account for quality control.
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