Construction of multi-strain microbial consortia producing amylase, serine and proline for enhanced bioconversion of food waste into lipopeptides

Abstract

The availability of precursor amino acids affects the production of lipopeptides. Its yield reached to 517.73 mg/L in the co-culture of Bacillus amyloliquefaciens HM618 with recombinant Corynebacterium glutamicum producing high-level serine. In the three-strain artificial consortium (TSAC) containing strains HM618 and engineered C. glutamicum producing serine and proline, the levels of turin A, fengycin, and surfactin reached 294.60, 171.12, and 108.90 mg/L, respectively. The total lipopeptide (574.62 mg/L) in TSAC was 1.97-fold higher than that in the pure culture strain HM618. To efficiently utilize starch in food waste (FW), engineered Pichia pastoris, which produces amylase, was introduced into TSAC to construct a four-strain artificial consortium (FSAC) for the bioconversion of FW into lipopeptides. Under an FW medium, the two-strain co-culture, TSAC, and FSAC had significantly enhanced lipopeptide production and amylase activity. Therefore, a mutualistic symbiosis in the artificial consortia of strains HM618 and engineered strains supplying amino acid precursors is beneficial to improve the lipopeptides co-production.