Whole genome sequencing and metabolomics analyses reveal the biosynthesis of nerol in a multi-stress-tolerant Meyerozyma guilliermondii GXDK6

Abstract

Background Nerol (C10H18O), an acyclic monoterpene, naturally presents in plant essential oils, and is used widely in food, cosmetics and pharmaceuticals as the valuable fragrance. Meanwhile, chemical synthesis is the only strategy for large-scale production of nerol, and the disadvantages of chemical synthesis greatly limit the production and its application. These defects drive the interests of researchers shift to the production of nerol by eco-friendly methods known as biosynthesis methods. However, the main technical bottleneck restricting the biosynthesis of nerol is the lacking of corresponding natural aroma-producing microorganisms. Results In this study, a novel multi-stress-tolerant probiotics Meyerozymaguilliermondii GXDK6 with aroma-producing properties was identified by whole genome sequencing and metabolomics technology. GXDK6 showed a broad pH tolerance in the range of 2.5–10.0. The species also showed salt tolerance with up to 12% NaCl and up to 18% of KCl or MgCl2. GXDK6 exhibited heavy-metal Mn2+ tolerance of up to 5494 ppm. GXDK6 could also ferment with a total of 21 kinds of single organic matter as the carbon source, and produce abundant aromatic metabolites. Results from the gas chromatography–mass spectrometry indicated the production of 8–14 types of aromatic metabolites (isopentanol, nerol, geraniol, phenylethanol, isobutanol, etc.) when GXDK6 was fermented up to 72 h with glucose, sucrose, fructose, or xylose as the single carbon source. Among them, nerol was found to be a novel aromatic metabolite from GXDK6 fermentation, and its biosynthesis mechanism had also been further revealed. Conclusion A novel aroma-producing M. guilliermondii GXDK6 was identified successfully by whole genome sequencing and metabolomics technology. GXDK6 showed high multi-stress-tolerant properties with acid–base, salty, and heavy-metal environments. The aroma-producing mechanism of nerol in GXDK6 had also been revealed. These findings indicated the aroma-producing M. guilliermondii GXDK6 with multi-stress-tolerant properties has great potential value in the fermentation industry.

Survival mechanism of a novel marine multistress-tolerant Meyerozyma guilliermondii GXDK6 under high NaCl stress as revealed by integrative omics analysis

“…Whole-genome sequence analysis showed that the total bases of GXDK6 were 2,477,073,673 bps, and its GC content accounted for 38.88%. The genome sequencing data were deposited to the National Microbiology Data Center database (http://nmdc.cn) under accession number NMDC60014229 (14). Compared genomic analysis showed that 14 genes (Table 1) related to salt tolerance were annotated, suggesting that GXDK6 is a high salt-tolerant strain, well consistent with the results shown in Fig.…”

“…1, GXDK6 was isolated from the subtropical marine mangrove sediments in the Beibu Gulf of China; its physicochemical characteristics were identified in previous studies (Figs. 1a-c) (14). The results showed that GXDK6 could continuously grow under a concentration of 0%-1% NaCl, indicating high salt tolerance (Fig.…”

“…Hmmscan software was used to predict the presence of carbohydrate-active enzyme (http://www.cazy.org) genes in the genome sequence (45,46). The whole-genome sequencing data of GXDK6 were deposited to the National Microbiology Data Center database (http://nmdc.cn) under accession number NMDC60014229 (14).…”

“…The previous study provided a novel multistress-tolerant Meyerozyma guilliermondii GXDK6, which showed broad pH tolerance (pH = 2.0-11.0) and high salt resistance (up to 14% NaCl or 18% KCl) (14). Its potential for non-sterile fermentation under high salt stress (12% NaCl) was also demonstrated.…”

Copper Tolerance Mechanism of the Novel Marine Multi-Stress Tolerant Yeast Meyerozyma guilliermondii GXDK6 as Revealed by Integrated Omics Analysis

“…Therefore, microorganisms with multiple stress tolerance and good heavy metal removal have gained interests. A previous study identified the multi stress tolerant yeast Meyerozyma guilliermondii GXDK6 with aroma-producing properties from subtropical marine mangrove wetland microorganisms ( Mo et al, 2021 ). This species can survive 1400 ppm (22 mM) copper ions, which is the highest tolerance concentration reported to date.…”