Artificial consortium that produces riboflavin regulates distribution of acetoin and 2,3‐butanediol by Paenibacillus polymyxa CJX518

Abstract

The introduction of an NADH/NAD+ regeneration system can regulate the distribution between acetoin and 2,3‐butanediol. NADH regeneration can also enhance butanol production in coculture fermentation. In this work, a novel artificial consortium of Paenibacillus polymyxa CJX518 and recombinant Escherichia coli LS02T that produces riboflavin (VB2) was used to regulate the NADH/NAD+ ratio and, consequently, the distribution of acetoin and 2,3‐butanediol by P. polymyxa. Compared with a pure culture of P. polymyxa, the level of acetoin was increased 76.7% in the P. polymyxa and recombinant E. coli coculture. Meanwhile, the maximum production and yield of acetoin in an artificial consortium with fed‐batch fermentation were 57.2 g/L and 0.4 g/g glucose, respectively. Additionally, the VB2 production of recombinant E. coli could maintain a relatively low NADH/NAD+ ratio by changing NADH dehydrogenase activity. It was also found that 2,3‐butanediol dehydrogenase activity was enhanced and improved acetoin production by the addition of exogenous VB2 or by being in the artificial consortium that produces VB2. These results illustrate that the coculture of P. polymyxa and recombinant E. coli has enormous potential to improve acetoin production. It was also a novel strategy to regulate the NADH/NAD+ ratio to improve the acetoin production of P. polymyxa.

Bioprocess Development for 2,3‐Butanediol Production by Paenibacillus Strains

“…Targeting in acetoin production, a low NADH/NAD + ratio occurred due to riboflavin production by E. coli that affected NADH dehydrogenase activity. The co‐culture reached 57.2 g L −1 of acetoin with 0.4 g g −1 yield 68.…”

Enhancement of polymyxin B1 production by an artificial microbial consortium of Paenibacillus polymyxa and recombinant Corynebacterium glutamicum producing precursor amino acids

“…Then, a 10-μL aliquot was examined with reversed-phase HPLC using an Aminex HPX-87H ion exclusion column (7.8 mm × 300 mm, Bio-Rad) and a differential refractive index detector. The mobile phase was 5.0 mM sulfuric acid in water at a flow rate of 0.6 mL/min, and the column temperature was maintained at 65°C [ 17 ]. The retention time of glucose was 9.3 min.…”

“…The impact of amino acid supplementation on polymyxin production is highly strain specific and dependent on the growth media [ 16 ]. Surfactin production can be increased by optimizing culture medium and fermentation strategy [ 17 ]. A combination of precursor amino acids can promote polymyxin synthesis.…”

Artificial Consortia of Bacillus Amyloliquefaciens HM618 and Bacillus Subtilis for Utilizing Food Waste to Synthetize Iturin A

“…10 µL of sample was determined by reversed-phase HPLC system equipped with Aminex HPX-87H Ion Exclusion particles column (7.8 mm×300 mm, BIORAD) and differential refractive index detector. The mobile phase was 5.0 mM sulfuric acid water at a ow rate of 0.6 mL/min and the column temperature was maintained at 65℃ (Liu et al 2017b). The retention time of glucose is 9.3 min.…”

“…Therefore, a reasonable distribution of substrates and metabolic intermediates in the mixed culture is of great signi cance for increasing the yield of iturin A. According to reports, by optimizing the inoculation amount of Bacillus polymyxa which could synthesis acetoin and the inoculation time of E coli that produces vitamin B2, the arti cial consortium can produce more acetoin (Liu et al 2017b). Similarly, in the co-culture fermentation with distiller's grains, optimizing the inoculum of two B. amyloliquefaciens resulted in an increase in the yield of surfactant to 2.54 g/L (Zhi et al 2017).…”