Genome sequencing and analysis of Gluconacetobacter tumulisoli FBFS97, a high-yield strain of phenyllactic acid

Abstract:

[Background] Phenyllactic acid (PLA) is a natural broad-spectrum antibacterial substance with a great application potential. In the previous work, Gluconacetobacter sp. FBFS97, an acetic acid bacterium (AAB) strain with high-yield PLA, was isolated, but the specific species of this strain and the molecular mechanism of PLA production is unclear. [Objective] To determine the species relationship of FBFS97, explore the genetic information of FBFS97, especially the genes related to PLA biosynthesis. [Methods] The morphology of FBFS97 was characterized by light microscopy and scanning electron microscopy, while the classification was identified by 16S rRNA gene sequence alignment. The effect of phenylalanine on FBFS97 producing PLA was detected by high-performance liquid chromatography (HPLC). On this basis, the complete genome was sequenced by Illumina MiSeq sequencers, and genome assembly, gene prediction, functional annotation, GO/COG cluster, metabolic pathway and virulence were analyzed using the relevant software, and the biosynthetic pathway of PLA is predicted. [Results] The strain was identified as Gluconacetobacter tumulisoli by 16S rRNA gene sequence alignment analysis and morphological analysis. When 1 000 mg/L phenylalanine was added to the liquid medium of FBFS97, the maximum concentration of PLA in the fermentation broth reached 400 mg/L, which was 8 times higher than that of control group. The genome size of FBFS97 is 3 988 308 bp with 66.62% (G+C)mol% and 3 500 encoding genes, and no toxin-related gene was predicted by VFDB database in the genome, and whole genes relative for biosynthetic PLA by the shikimate pathway were found. [Conclusion] This is first attempt to describe the whole genome sequence of Gluconacetobacter tumulisoli sp. FBFS97, a high-yield strain of PLA. The genes related to PLA biosynthesis are found in the FBFS97 genome, which provides a basis for further investigation on the PLA biosynthetic pathway in FBFS97.