Showing papers in "Metabolic Engineering in 2019"

TL;DR: This review summarizes and categorizes the applications of Adaptive Laboratory Evolution to various aspects of microbial physiology pertinent to industrial bioproduction by collecting case studies that highlight the multitude of ways in which evolution can facilitate the strain construction process.

TL;DR: This study overexpressed key genes associated with fatty acid synthesis and TAG production, followed by modulation of TAG fatty acyl composition by overexpressing a fatty acid desaturase (OLE1) and deletion of Seipin (FLD1), which regulates lipid-droplet size to enable increased lycopene accumulation.

TL;DR: This work presents another successful example of the modularization of metabolic pathways for improving titer and yield in biotechnological production and may pave the way for the commercial production of green surfactin.

TL;DR: This work developed microbial co-cultures composed of multiple metabolically engineered E. coli strains for heterologous biosynthesis of complex natural product rosmarinic acid whose biosynthesis involves a complex diverging-converging pathway and demonstrated the strong potentials of modular co-culture engineering for overcoming the challenges ofcomplex natural product biosynthesis involving non-linear pathways.

TL;DR: It is demonstrated that acetate uptake pathway in oleaginous yeast (Yarrowia lipolytica) could function as an acetyl-CoA shortcut to achieve metabolic optimality in producing polyketides and highlights that low-cost acetic acid could be sustainably upgraded to high-value polyketide species in an eco-friendly and cost-efficient manner.

TL;DR: By overexpressing a single gene, it is possible to significantly improve the citric acid secretion capability of a moderately producing parental strain and demonstrate the importance of the cellular transport system for an efficient production of metabolites.

TL;DR: The yeast ER can be engineered as a specialized compartment for enhancing terpene production, representing new possibilities for the high-level production of other value-added chemicals.

TL;DR: In this review, recent progress in metabolic engineering strategies to enhance membrane integrity, regulate membrane fluidity, and tune membrane permeability are summarized.

TL;DR: A significant advancement of flavone synthetic production is presented and provides foundation for production of other flavones in microbial hosts.

TL;DR: A fully integrated and plasmid-free yeast strain is engineered with enhanced production of the monoterpene precursor geraniol and the strategies developed can facilitate future strain engineering for yeast production of later intermediates in the strictosidine biosynthetic pathway.

TL;DR: A novel approach for accurate, precise and convenient 13C metabolic flux analysis of Pseudomonas putida KT2440 and the human pathogen P. aeruginosa PAO1, which displays a valuable extension of the available set of flux methods for these types of bacteria.

TL;DR: The design principles of engineering burden-driven feedback control to combat metabolic stress, implementing population quality control to eliminate cheater cell, applying product addiction to reward productive cell, as well as layering dual dynamic regulation to decouple cell growth from product formation are summarized.

TL;DR: It is demonstrated that improving phosphoenolpyruvate supply by expressing pyruvates kinase variants and eliminating the formation of p-hydroxy-phenylethanol without creating tyrosine auxotrophy significantly contributed to improve 2PE production in S. cerevisiae.

TL;DR: This study systematically optimized an auxotrophic Escherichia coli to produce viridiflorol with transcription, translation, enzyme and strain engineering, paving the way for commercialization of microbial terpenoid production.

TL;DR: This study shows that syntrophic cultures offer a flexible platform for metabolite production with superior carbon recovery that can also be applied to electron-enhanced fermentations enabling even higher carbon recoveries, and shows that direct cell-to-cell interactions and material exchange among the two microbes enabled unforeseen rearrangements in the metabolism of the individual species.

TL;DR: Adaptive laboratory evolution was used to explore the tolerance mechanisms that Saccharomyces cerevisiae can evolve in the presence of inhibiting concentrations of three dicarboxylic acids, and the amplification of QDR3 was shown to confer tolerance towards muconic acid and glutaconic acid.

TL;DR: A significant improvement to the HA titer in a safe and efficient host by systematic metabolic engineering based on a genome-scale metabolic model iCW773 is reported.

TL;DR: The central carbon and redox metabolism of Bacillus subtilis was reprogramed and a "push-pull-promote" approach efficiently reduced the overflown acetyl-CoA flux and eliminated byproduct formation.

TL;DR: A methodology to quantify the cutting efficiency of each sgRNA in a genome-scale library is developed and in doing so improve screens in the biotechnologically important yeast Yarrowia lipolytica, and identifies novel mutations for metabolic engineering of high lipid accumulation.

TL;DR: It is demonstrated that the yeast species Saccharomyces cerevisiae and Yarrowia lipolytica both can be engineered to produce 2'-fucosyllactose (2'FL), which is the most abundant oligosaccharide in human breast milk, at high titer and productivity.

TL;DR: The data suggest that the cellular redox state, rather than the acetyl-CoA pool, was limiting PHB production, and advances the fundamental understanding of heterologous product synthesis in gas-fermenting acetogens.

TL;DR: The system developed in this study overcomes the deficiencies of currently available genetic tools in the chromosomal integration of large DNA fragments (rapid, markerless and stable) in C. ljungdahlii, and may be extended to other Clostridium species.

TL;DR: Results highlight how conserved metabolic features in a platform bacterium can be rationally reshaped for enhancing physiological traits of interest.

TL;DR: The design, characterization, and impact of ncRNAs in engineering both native and exogenous metabolic pathways in bacteria are reviewed and the opportunities afforded by recent high-throughput approaches for characterizing sRNA regulators and their corresponding networks are considered to showcase their potential applications and impact in engineering bacterial metabolism.

TL;DR: In the industrial oleaginous microalga Nannochloropsis oceanica, transcript knockdown of a cytosolic carbonic anhydrase (CA2), which is a key Carbon Concentrating Mechanism (CCM) component induced under 100 ppm CO2 (very low carbon, or VLC), results in ∼45, ∼30, and ∼40% elevation of photosynthetic oxygen evolution rate, growth rate and biomass accumulation rate respectively under 5% CO2, as compared to the wild type as discussed by the authors.

TL;DR: This study is the first adaptation of a genome scale model for CHO cells to an industrial process, that successfully predicted cell phenotype, and sheds light on the metabolic specificities of a high production process.

TL;DR: This study designed a shortcut pathway of L-aspartate biosynthesis in Escherichia coli, with a maximized stoichiometric yield of 2 mol/mol glucose and the highest yield of β-alanine reported so far.

TL;DR: Next-generation industrial biotechnology (NGIB) based on recombinant H. bluephagenesis grown under unsterile and continuous conditions, allows production of P(3HB-0∼25mol% 3HV) in a convenient way with reduced production complexity and cost.

TL;DR: This work discovered the oleaginous yeast Yarrowia lipolytica can grow in 10% (v/v) of 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]), which makes it more tolerant than most engineered microorganisms and naturally screened isolates, and discovered that sterols play a key role for exceptional IL tolerance in Y. lipolyTica.

TL;DR: It appears that the PHA granular sizes could be limited by bacterial cell sizes, and by engineering a large cell morphology large PHAgranules can be produced by PhaP deleted mutants.