Microbial instability is a common problem during bio-production based on microbial hosts. Halomonas bluephagenesis has been developed as a chassis for next generation industrial biotechnology (NGIB) under open and unsterile conditions. However, the hidden genomic information and peculiar metabolism have significantly hampered its deep exploitation for cell-factory engineering.
View Article and Find Full Text PDFHalophilic Halomonas bluephagenesis has been engineered to produce various added-value bio-compounds with reduced costs. However, the salt-stress regulatory mechanism remained unclear. H.
View Article and Find Full Text PDFPolyhydroxyalkanoates (PHAs) are microbial polyesters that have the potential to replace nonbiodegradable petroplastics. A real-time in situ PHA quantification method has long been awaited to replace the traditional method, which is time- and labor-consuming. Quantification of PHA in living cells was finally developed from fluorescence intensities generated from the green fluorescence protein (GFP) fused with the phasin proteins.
View Article and Find Full Text PDFHalomonas bluephagenesis has been engineered to produce flexible copolymers P34HB or poly(3-hydroxybutyrate-co-4-hydroxybutyrate) from glucose and petrol-chemical precursor, γ-butyrolactone. Herein, gene cluster aldD-dhaT was constructed in recombinant H. bluephagenesis for catalyzing 1,4-butanediol (BDO) into 4-hydroxybutyrate, which could grow to 86 g L dry cell mass (DCM) containing 77 wt% P(3HB-co-14 mol% 4HB) in 7-L bioreactor fed with glucose and bio-based BDO.
View Article and Find Full Text PDFEctoine, a compatible solute synthesized by many halophiles for hypersalinity resistance, has been successfully produced by metabolically engineered Halomonas bluephagenesis, which is a bioplastic poly(3-hydroxybutyrate) producer allowing open unsterile and continuous conditions. Here we report a de novo synthesis pathway for ectoine constructed into the chromosome of H. bluephagenesis utilizing two inducible systems, which serve to fine-tune the transcription levels of three clusters related to ectoine synthesis, including ectABC, lysC and asd based on a GFP-mediated transcriptional tuning approach.
View Article and Find Full Text PDFOptimization of intracellular biosynthesis process involving regulation of multiple gene expressions is dependent on the efficient and accurate expression of each expression unit independently. However, challenges of analyzing intermediate products seriously hinder the application of high throughput assays. This study aimed to develop an engineering approach for unsterile production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) or (P3HB4HB) by recombinant Halomonas bluephagenesis (H.
View Article and Find Full Text PDFPromoters for the expression of heterologous genes in Halomonas bluephagenesis are quite limited, and many heterologous promoters function abnormally in this strain. P, a promoter of the strongest expressed protein porin in H. bluephagenesis, is one of the few promoters available for heterologous expression in H.
View Article and Find Full Text PDFPoly(3-hydroxybutyrate-co-4-hydroxybutyrate), P(3HB-co-4HB), is one of the most valuable biopolymers because of its flexible mechanical properties. In this study, the goal is to establish a scaled-up process of low cost P(3HB-co-4HB) from a 7.5-L fermentor to 1- and 5-m industrial bioreactors, respectively, using Halomonas bluephagenesis TD40 grown on glucose, γ-butyrolactone, and waste corn steep liquor (CSL) as substrates, under open non-sterile and fed-batch or continuous conditions.
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