The Discovery of Membrane Vesicle Biogenesis in the Polyhydroxybutyrate-non-producing Mutant Strain of Cupriavidus necator H16.

Extracellular membrane vesicles (MVs) caused by the artificial production of polyhydroxybutyrate (PHB) were previously detected in Escherichia coli. We herein observed MV biogenesis in the mutant strain (-PHB) of the natural PHB producer, Cupriavidus necator H16. This inverse relationship was revealed through comparative electron microscopic ana-lyses of wild-type and mutant strains.

Synthesis of a natural core substrate with lignin-xylan cross-linkage for unveiling the productive kinetic parameters of glucuronoyl esterase.

Lignin-carbohydrate complexes (LCCs) present a considerable hurdle to the economic utilization of lignocellulosic biomass. Glucuronoyl esterase (GE) is an LCC-degrading enzyme that catalyzes the cleavage of the cross-linkages between lignin and xylan in LCCs. Benzyl-d-glucuronate (Bn-GlcA), a commercially available substrate, is widely used to evaluate GE activity assays.

Complete sequence randomness of lactate-based copolymers (LAHBs) with varied lactate monomer fractions employing a series of propionyl-CoA transferases.

Previously, we biosynthesized an evolved version of a bio-based polylactide (PLA) on microbial platforms using our engineered lactate-polymerizing enzyme (LPE). This lactate (LA)-based copolyester, LAHB, has advantages over PLA, including improved flexibility and biodegradability, and its properties can be regulated through the LA fraction. To expand the LA-incorporation capacity and improve polymer properties, in the state of in vivo LAHB production, propionyl-CoA transferases (PCTs) that exhibited enhanced production of LA-CoA than the conventional PCTs were selected.

Modification of poly(lactate) via polymer blending with microbially produced poly[(R)-lactate-co-(R)-3-hydroxybutyrate] copolymers.

This study investigated the effect of polymer blending of microbially produced poly[(R)-lactate-co-(R)-3-hydroxybutyrate] copolymers (LAHB) with poly(lactate) (PLA) on their mechanical, thermal, and biodegradable properties. Blending of high lactate (LA) content and high molecular weight LAHB significantly improved the tensile elongation of PLA up to more than 250 % at optimal LAHB composition of 20-30 wt%. Temperature-modulated differential scanning calorimetry and dynamic mechanical analysis revealed that PLA and LAHB were immiscible but interacted with each other, as indicated by the mutual plasticization effect.

Cell-growth phase-dependent promoter replacement approach for improved poly(lactate-co-3-hydroxybutyrate) production in Escherichia coli.

Escherichia coli is a useful platform for producing valuable materials through the implementation of synthetic gene(s) derived from other organisms. The production of lactate (LA)-based polyester poly[LA-co-3-hydroxybutyrate (3HB)] was carried out in E. coli using a set of five other species-derived genes: Pseudomonas sp.

Acceleration of the Dehydrogenation of d-Glucose to 2-Keto-d-gluconate in Aqueous Amino Acid via Hydrated Stacked Clay Nanosheets.

The assembly of discrete active species to form periodical nanostructures is essential in realizing low-cost artificial enzymes that mimic natural enzymatic functions in extraordinary bio(chemo)selective reactions. In this study, we developed artificial bifunctional glucose/gluconic acid dehydrogenase from naturally abundant resources: l-aspartic acid (Asp) and montmorillonite (a subgroup of smectite natural clay minerals). β-d-Glucose (Glc) was dehydrogenated to 2-keto-d-gluconate (2-KGA) at 25 and 30 °C in an aqueous acidic solution (pH = 3, 4, and 5).

Controllable secretion of multilayer vesicles driven by microbial polymer accumulation.

Membrane vesicles (MVs) are formed in various microorganisms triggered by physiological and environmental phenomena. In this study, we have discovered that the biogenesis of MV took place in the recombinant cell of Escherichia coli BW25113 strain that intracellularly accumulates microbial polyester, polyhydroxybutyrate (PHB). This discovery was achieved as a trigger of foam formation during the microbial PHB fermentation.

Xylanase from Marine Filamentous Fungus sp. AN-7 Was Activated with Diluted Salt Solution Like Brackish Water.

The genus are endophytic fungi that have recently been identified as cellulolytic system producers. We herein cloned a gene coding for a xylanase belonging to glycoside hydrolase (GH) family 10 (Xyn10A) from sp. AN-7, which was isolated from the soil of a mangrove forest.

Characterization of Acetylxylan Esterase from White-Rot Fungus .

The carbohydrate esterase family 1 (CE1) in CAZy contains acetylxylan esterases (AXEs) and feruloyl esterases (FAEs). Here we cloned a gene coding for an AXE belonging to CE1 from (AXE1). AXE1 was heterologously expressed in , and the recombinant enzyme was purified and characterized.