Metagenomics and Metagenome-Assembled Genomes Analysis of Highland Barley Baijiu Daqu

Highland barley Baijiu is a kind of fermented liquor with national characteristics produced in the Qinghai-Tibet Plateau, and its quality largely depends on the highland barley Baijiu Daqu (HBQ). HBQ contains abundant microbial resources and embedded unknown genomes that have not yet been decoded. In order to deeply understand the key contribution of microorganisms in HBQ, this study analyzed the microbial community structure of HBQ, inferred predicted functions and recovered high-quality metagenome-assembled genomes (MAGs) based on Metagenomics. The results indicated that <i>Pantoea agglomerans</i> was the most abundant species in HBQ, followed by <i>Lichtheimia ramosa</i>, <i>Pichia kudriavzevii</i>, <i>Saccharomycopsis fibuligera</i> and <i>Wickerhamomyces anomalus</i>. The predictive function of the HBQ was focused on annotating carbohydrate metabolism and amino acid metabolism. Meanwhile, six high-quality MAG strains were recovered and identified as <i>Unclassified Kroppenstedtia</i>, <i>Erwinia persicina</i>, <i>Leuconostoc citreum</i>, <i>Saccharopolyspora rectivirgula</i>, <i>Levilactobacillus brevis</i>, and <i>Pantoea agglomerans</i>. Genome annotation of the recovered genomes showed eggNOG predicted function as well as primary and secondary metabolites. The metabolic network diagram of the functional microorganisms in HBQ related to flavor compounds was also predicted. The results can help to understand the formation mechanism of flavor profiles in highland barley Baijiu.