Metabolic engineering of Escherichia coli for enhanced production of p-coumaric acid via L-phenylalanine biosynthesis pathway.

p-Coumaric acid (p-CA), an invaluable phytochemical, has novel bioactivities, including antiproliferative, anxiolytic, and neuroprotective effects, and is the main precursor of various flavonoids, such as caffeic acid, naringenin, and resveratrol. Herein, we report the engineering of Escherichia coli for de novo production of p-CA via the PAL-C4H pathway. As the base strain, we used the E.

Metabolic Engineering of Corynebacterium glutamicum for High-Level Production of 1,5-Pentanediol, a C5 Diol Platform Chemical.

The biobased production of chemicals is essential for advancing a sustainable chemical industry. 1,5-Pentanediol (1,5-PDO), a five-carbon diol with considerable industrial relevance, has shown limited microbial production efficiency until now. This study presents the development and optimization of a microbial system to produce 1,5-PDO from glucose in Corynebacterium glutamicum via the l-lysine-derived pathway.

Engineering of Pseudomonas putida to produce medium-chain-length polyhydroxyalkanoate from crude glycerol.

The development of biodegradable polymers is crucial for addressing environmental issues and waste management challenges, and a medium-chain-length polyhydroxyalkanoate(MCL-PHA) exhibits significant application potential in diverse industrial and environmental contexts owing to its versatility and biodegradability. Here, Pseudomonas putida was metabolically engineered to produce MCL-PHA from crude glycerol. To increase the precursor pool, we first deleted the phaC1ZC2 operon and introduced a plasmid-based overexpression of phaC2 and phaG, and the MCL-PHA content derived from glycerol increased to 18.

Design of fully synthetic signal peptide library and its use for enhanced secretory production of recombinant proteins in Corynebacterium glutamicum.

Background: Corynebacterium glutamicum is an attractive host for secretory production of recombinant proteins, including high-value industrial enzymes and therapeutic proteins. The choice of an appropriate signaling peptide is crucial for efficient protein secretion. However, due to the limited availability of signal peptides in C.

Engineering of Recombinant Human Papillomavirus 16 L1 Protein for Incorporation with -Azido--Phenylalanine.

Human papillomavirus (HPV) L1 capsid protein were produced in several host systems, but few studies have focused on enhancing the properties of the L1 protein. In this study, we aimed to produce recombinant Human papillomavirus (HPV) L1 capsid protein containing -azido--phenylalanine (pAzF) in . First, we expressed the maltose-binding protein (MBP)-fused HPV16 L1, and 5 residues in HPV16 L1 protein were selected by the in silico modeling for amber codon substitution.

Serial adaptive laboratory evolution enhances mixed carbon metabolic capacity of Escherichia coli.

Microbes have inherent capacities for utilizing various carbon sources, however they often exhibit sub-par fitness due to low metabolic efficiency. To test whether a bacterial strain can optimally utilize multiple carbon sources, Escherichia coli was serially evolved in L-lactate and glycerol. This yielded two end-point strains that evolved first in L-lactate then in glycerol, and vice versa.

Intracellular Flux Prediction of Recombinant Producing Gamma-Aminobutyric Acid.

Genome-scale metabolic model (GEM) can be used to simulate cellular metabolic phenotypes under various environmental or genetic conditions. This study utilized the GEM to observe the internal metabolic fluxes of recombinant producing gamma-aminobutyric acid (GABA). Recombinant was cultivated in a fermenter under three conditions: pH 7, pH 5, and additional succinic acids.

Enhanced production of difficult-to-express proteins through knocking down rnpA gene expression.

Escherichia coli has been employed as a workhorse for the efficient production of recombinant proteins. However, some proteins were found to be difficult to produce in E. coli.

Rapid combinatorial rewiring of metabolic networks for enhanced poly(3-hydroxybutyrate) production in Corynebacterium glutamicum.

Background: The disposal of plastic waste is a major environmental challenge. With recent advances in microbial genetic and metabolic engineering technologies, microbial polyhydroxyalkanoates (PHAs) are being used as next-generation biomaterials to replace petroleum-based synthetic plastics in a sustainable future. However, the relatively high production cost of bioprocesses hinders the production and application of microbial PHAs on an industrial scale.

Production of 1,2-propanediol from glycerol in Klebsiella pneumoniae GEM167 with flux enhancement of the oxidative pathway.

Background: To support the sustainability of biodiesel production, by-products, such as crude glycerol, should be converted into high-value chemical products. 1,2-propanediol (1,2-PDO) has been widely used as a building block in the chemical and pharmaceutical industries. Recently, the microbial bioconversion of lactic acid into 1,2-PDO is attracting attention to overcome limitations of previous biosynthetic pathways for production of 1,2-PDO.

Systematic metabolic engineering of Escherichia coli for the enhanced production of cinnamaldehyde.

Cinnamaldehyde (CAD) derived from cinnamon bark has received much attention for its potential as a nematicide and food additive. Previously, we have succeeded in developing an Escherichia coli strain (YHP05) capable of synthesizing cinnamaldehyde; however, the production titer (75 mg/L) was not sufficient for commercialization. Herein, to develop an economical and sustainable production bioprocess, we further engineered the YHP05 strain for non-auxotrophic, antibiotic-free, inducer-free hyperproduction of CAD using systematic metabolic engineering.

Engineering of for Efficient Bioconversion of Soy Isoflavone Glycosides to Their Aglycone Forms.

Soy isoflavones are phytochemicals that possess various beneficial physiological properties such as anti-aging, anti-tumor, and antioxidant properties. Since soy isoflavones exist in glycoside forms, their bioavailability requires initial hydrolysis of the sugar moieties bound to them to be efficiently absorbed through the gut epithelium. Instead of conventional chemical hydrolysis using acids or organic solvents, alternative strategies for enhancing the bioavailability of soy isoflavones using biological methods are gaining attention.

Production of Cinnamaldehyde through Whole-Cell Bioconversion from -Cinnamic Acid Using Engineered .

Cinnamaldehyde (CAD) has various applications in foods and pharmaceuticals and has gained prominence as a potent nematicide in agricultural research owing to its nematicidal activity. However, conventional methods of CAD production, including extraction from plants or organic chemical synthesis, are environmentally hazardous and limit its utilization for downstream applications. Here, we engineered as a whole-cell biocatalyst for the efficient bioconversion of -cinnamic acid (-CA) into CAD.

Safe-Harboring based novel genetic toolkit for Nannochloropsis salina CCMP1776: Efficient overexpression of transgene via CRISPR/Cas9-Mediated Knock-in at the transcriptional hotspot.

Transgene expression in microalgae can be hampered by transgene silencing and unstable expression due to position effects. To overcome this, "safe harboring" transgene expression system was established for Nannochloropsis. Initially, transformants were obtained expressing a sfGFP reporter, followed by screening for high expression of sfGFP with fluorescence-activated cell sorter (FACS).

Enhanced production of neoagarobiose from agar with Corynebacterium glutamicum producing exo-type and endo-type β-agarases.

Neoagarobiose (NA2) derived from agar marine biomass is a rare reagent that acts as an anti-melanogenesis reagent and moisturizer. Here, for the economical manufacturing of NA2, we developed the co-secretory production system of endo-type β-agarases (DagA) and exo-type β-agarases (EXB3) in Corynebacterium glutamicum. For this purpose, we first developed a secretory system of DagA via Tat pathway.

Production of trans-cinnamic acid by whole-cell bioconversion from L-phenylalanine in engineered Corynebacterium glutamicum.

Background: trans-cinnamic acid (t-CA) is a phenylpropanoid with a broad spectrum of biological activities including antioxidant and antibacterial activities, and it also has high potential in food and cosmetic applications. Although significant progress has been made in the production of t-CA using microorganisms, its relatively low product titers still need to be improved. In this study, we engineered Corynebacterium glutamicum as a whole-cell catalyst for the bioconversion of L-phenylalanine (L-Phe) into t-CA and developed a repeated bioconversion process.

Development of CRISPR Interference (CRISPRi) Platform for Metabolic Engineering of and Its Application for Engineering Riboflavin Biosynthesis.

, a hetero-fermentative type of lactic acid bacteria, is a crucial probiotic candidate because of its ability to promote human health. However, inefficient gene manipulation tools limit its utilization in bioindustries. We report, for the first time, the development of a CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) interference (CRISPRi) system for engineering .

Development and characterization of a mutant with simultaneously enhanced growth and lipid production.

Background: The necessity to develop high lipid-producing microalgae is emphasized for the commercialization of microalgal biomass, which is environmentally friendly and sustainable. are one of the best industrial microalgae and have been widely studied for their lipids, including high-value polyunsaturated fatty acids (PUFAs). Many reports on the genetic and biological engineering of to improve their growth and lipid contents have been published.

Plasmid Display for Stabilization of Enzymes Inside the Cell to Improve Whole-Cell Biotransformation Efficiency.

Recombinant whole-cell biocatalysts are widely used for biotransformation of valuable products. However, some key enzymes involved in biotransformation processes are unstable and cannot be easily expressed in the functional form. In this study, we describe a versatile platform for enzyme stabilization inside the cell: Intracellularly Immobilized Enzyme System (IIES).

Enhanced production of styrene by engineered Escherichia coli and in situ product recovery (ISPR) with an organic solvent.

Background: Styrene is a large-volume commodity petrochemical, which has been used in a wide range of polymer industry as the main building block for the construction of various functional polymers. Despite many efforts to produce styrene in microbial hosts, the production titers are still low and are not enough to meet the commercial production of styrene.

Results: Previously, we developed a high L-phenylalanine producer (E.

Recent advances in engineering Corynebacterium glutamicum for utilization of hemicellulosic biomass.

Corynebacterium glutamicum has been mainly used for industrial production of amino acids, and in recent years, it has also been successfully engineered to broaden its range of substrate and product profiles. In particular, C. glutamicum has been engineered to use non-natural sugar substrates (mainly pentoses) derived from hemicellulosic feedstock, which is the second abundant component of lignocellulosic biomass.

Robust Thin Film Surface with a Selective Antibacterial Property Enabled via a Cross-Linked Ionic Polymer Coating for Infection-Resistant Medical Applications.

Fabrication of new antibacterial surfaces has become a primary strategy for preventing device-associated infections (DAIs). Although considerable progress has recently been made in reducing DAIs, current antibacterial coating methods are technically complex and do not allow selective bacterial killing. Here, we propose novel anti-infective surfaces made of a cross-linked ionic polymer film that achieve selective bacteria killing while simultaneously favoring the survival of mammalian cells.

Development of bicistronic expression system for the enhanced and reliable production of recombinant proteins in Leuconostoc citreum.

The lactic acid bacteria (LAB) Leuconostoc citreum are non-sporulating hetero-fermentative bacteria that play an important role in the fermented food industry. In this study, for the enhanced and reliable production of recombinant proteins in L. citreum, we developed a bicistronic design (BCD) expression system which includes a short leader peptide (1 cistron) followed by target genes (2 cistron) under the control of a single promoter.