Bacillus aquiflavi 3H-10 is the first strain of brewing novel species, isolated from yellow water of strong-flavor Chinese Baijiu in Yibin, Sichuan province. In order to explore its function characteristics, the whole genome sequence of B. aquiflavi 3H-10 was determined by high-throughput sequencing. And potential functional genes, biological enzymes and fermentation flavor substances were analyzed with BLAST against sequence database, plate transparent circle method, Folin-Ciocalteu method and GC-MS. The results showed that the genome size of B. aquiflavi 3H-10 was 3.62 MB and the G+C content was 35.40 mol% with 3 224 protein-coding genes predicted. Analysis with KEGG, NR and CAZy databases showed that the genome harbors genes responsible for 22 proteases and various carbohydrate enzymes. Clear transparent circle was observed for B. aquiflavi 3H-10 on the protease medium plate and the protease enzyme activity was 85 U/mL. After cultivation in TSB at 37 ℃ for 72 h, the strain could produce 56 metabolic flavor compounds, including esters, alcohols, aromatics, carbonyl compounds and heterocyclic compounds, etc. Among them, the substances with relatively high contents include benzaldehyde (almond flavor, nut flavor), 2,5-dimethylpyrazine (fried sesame flavor), n-butanol (fruit flavor), 3- methylhexanol and ethyl hexanoate (sweet, fruity, cellar and cucumber), the main flavoring substrate of strong-flavor Chinese Baijiu. Our study demonstrated that B. aquiflavi 3H-10 had significant protease-producing ability and could produce various flavor substances by fermentation, which promoted the formation of flavors in strong-flavor Chinese Baijiu. It was speculated that B. aquiflavi 3H-10 had potential application value in Chinese Baijiu fermentation.
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