Effects of heat stress on development, reproduction and activities of protective enzymes in Mononychellus mcgregori.

Mononychellus mcgregori is a pest mite of cassava. Since its invasion into China in 2008 it has spread rapidly. In order to determine the potential distribution and to analyze its invasion, diffusion and ecological adaptation mechanisms, we investigated the effect of high-temperature stress (30, 33, 36, 39 and 42 °C) on its development and reproduction, and the activity of protective enzymes in the mite.

Improving the secretion of cadaverine in Corynebacterium glutamicum by cadaverine-lysine antiporter.

Cadaverine (1,5-pentanediamine, diaminopentane), the desired raw material of bio-polyamides, is an important industrial chemical with a wide range of applications. Biosynthesis of cadaverine in Corynebacterium glutamicum has been a competitive way in place of petroleum-based chemical synthesis method. To date, the cadaverine exporter has not been found in C.

Purification and characterization of a thermostable xylanase from Paenibacillus sp. NF1 and its application in xylooligosaccharides production.

High levels of extracellular xylanase activity (211.79 IU/mg) produced by Paenibacillus sp. NF1 were detected when it was submerged-cultured.

[High-efficiency L-lactate production from glycerol by metabolically engineered Escherichia coli].

High-efficient conversion of glycerol to L-lactate is beneficial for the development of both oil hydrolysis industry and biodegradable materials manufacturing industry. In order to construct an L-lactate producer, we first cloned a coding region of gene BcoaLDH encoding an L-lactate dehydrogenase from Bacillus coagulans CICIM B1821 and the promoter sequence (P(ldhA)) of the D-lactate dehydrogenase (LdhA) from Escherichia coli CICIM B0013. Then we assembled these two DNA fragments in vitro and yielded an expression cassette, P(ldhA)-BcoaLDH.

Improvement of alkali stability and thermostability of Paenibacillus campinasensis Family-11 xylanase by directed evolution and site-directed mutagenesis.

The extreme process condition of high temperature and high alkali limits the applications of most of natural xylanases in pulp and paper industry. Recently, various methods of protein engineering have been used to improve the thermal and alkalic tolerance of xylanases. In this work, directed evolution and site-directed mutagenesis were performed to obtain a mutant xylanase improved both on alkali stability and thermostability from the native Paenibacillus campinasensis Family-11 xylanase (XynG1-1).

Secretory expression, functional characterization, and molecular genetic analysis of novel halo-solvent-tolerant protease from Bacillus gibsonii.

A novel protease gene from Bacillus gibsonii, aprBG, was cloned, expressed in B. subtilis, and characterized. High-level expression of aprBG was achieved in the recombinant strain when a junction was present between the promoter and the target gene.

Construction of engineered Arthrobacter simplex with improved performance for cortisone acetate biotransformation.

Arthrobacter simplex 156 is a microorganism that is used for steroid drug biotransformation of cortisone acetate (CA) to prednisone acetate (PA). The enzyme 3-ketosteroid-△(1)-dehydrogenase encoded by the ksdD gene plays an important role in the bioconversion process. To further improve the biotransformation efficiencies of the industrial strain, a genetic manipulation system for A.

Profiling of dynamic changes in the microbial community during the soy sauce fermentation process.

Soy sauce is a traditional condiment manufactured by natural inoculation and mixed culture fermentation. As is well known, it is the microbial community that plays an important role in the formation of its flavors. However, to date, its dynamic changes during the long period of fermentation process are still unclear, intensively constraining the improvement and control of the soy sauce quality.

Construction of an engineering strain producing high yields of α-transglucosidase via Agrobacterium tumefaciens-mediated transformation of Asperillus niger.

In this study, Agrobacterium tumefaciens-mediated transformation (ATMT) was used in breeding industrial strains for the purpose of improving α-transglucosidase production. Firstly, an efficient ATMT system for Asperillus niger was established by optimization of several influencing factors, in which transformation efficiency was improved up to 14-fold compared with the initial conditions. Furthermore, binary vector pBI-Glu containing an α-transglucosidase expression cassette was constructed and transferred into Agrobacterium tumefaciens LBA4404 in order to infect A.

[Temperature-switched high-efficiency D-lactate production from glycerol].

Glycerol from oil hydrolysis industry is being considered as one of the abundent raw materials for fermentation industry. In present study, the aerobic and anaerobic metabolism and growth properties on glycerol by Esherichia coli CICIM B0013-070, a D-lactate over-producing strain constructed previously, at different temperatures were investigated, followed by a novel fermentation process, named temperature-switched process, was established for D-lactate production from glycerol. Under the optimal condition, lactate yield was increased from 64.

Overexpression of a Paenibacillus campinasensis xylanase in Bacillus megaterium and its applications to biobleaching of cotton stalk pulp and saccharification of recycled paper sludge.

A xylanase gene (xynG1-1) from Paenibacillus campinasensis G1-1 was expressed in Bacillus megaterium MS941 and a high level of extracellular xylansae activity (304.26 IU/mL) was achieved after induction with 0.5% xylose.

Crystallization and preliminary X-ray diffraction analysis of a novel GH120 β-xylosidase (XylC) from Thermoanaerobacterium saccharolyticum JW/SL-YS485.

Xylosidases hydrolyze xylopolymers at the nonreducing end to free xylose units. The β-xylosidase (XylC) from Thermoanaerobacterium saccharolyticum JW/SL-YS485 was expressed in Escherichia coli and the recombinant protein was purified and crystallized. A BLASTP search with the XylC protein sequence showed that no similar structure had previously been solved.

15α-Hydroxylation of a steroid (13-ethyl-gon-4-en-3,17-dione) by Penicillium raistrickii in an ionic liquid/aqueous biphasic system.

Biphasic processes are used in whole-cell biotransformation to overcome the low water solubility of substrates and products as well as their inhibitory effects on the biocatalyst. Commercially available [NTf(2)]- and [PF(6)]-based ionic liquids (ILs) were used in a biphasic system for the 15α-hydroxylation of 13-ethyl-gon-4-en-3,17-dione by Penicillium raistrickii. With the substrate at 5 g l(-1) and a volume ratio of IL to buffer, buffer pH and cell density at, 1:9, 6.

Adsorption characteristics of malic acid from aqueous solutions by weakly basic ion-exchange chromatography.

In this study, we reported the effects of temperature, malic acid loading concentration, and resin dose on malic acid adsorption by IRA-67 in batch experiments. The kinetic data well fitted the pseudo-second-order kinetic model. Both the equilibrium and ultimate adsorption slightly decreased with increased temperature from 303 to 323 K at 74.

Isolation, purification, and characterization of a thermostable xylanase from a novel strain, Paenibacillus campinasensis G1-1.

High levels of xylanase activity (143.98 IU/ml) produced by the newly isolated Paenibacillus campinasensis G1-1 were detected when it was cultivated in a synthetic medium. A thermostable xylanase, designated XynG1-1, from P.

Construction of Escherichia coli strains producing L-serine from glucose.

L-Serine is usually produced from glycine. We have genetically engineered Escherichia coli to produce L-serine from glucose intracellularly. D-3-Phosphoglycerate dehydrogenase (PGDH, EC 1.

Efficient expression of an alkaline pectate lyase gene from Bacillus subtilis and the characterization of the recombinant protein.

The gene encoding a novel alkaline pectate lyase (Apel) from Bacillus subtilis was cloned and expressed in B. subtilis WB600. Apel contained an ORF of 1,260 bp, encoding a signal peptide of 21 amino acids and a mature protein of 399 amino acids with a calculated molecular mass of 45497.

Synthesis of GDP-mannose using coupling fermentation of recombinant Escherichia coli.

Glucokinase (glk), phosphomannomutase (manB), and mannose-1-phosphate guanylytransferase (manC) are needed for the biosynthesis of GDP-mannose. A recombinant E. coli strain over-expressing these three genes was constructed to produce guanosine 5'-diphosphate (GDP)-mannose, the donor of GDP-fucose, an essential substrate for synthesis of fucosyloligosaccharides.

[Research progress on mutation by spaceflight in medicinal plants breeding].

Space breeding in medicinal plants is special characteristics in China. Compared with other plants, in spite of a relatively small number, Medicinal plants have more obvious characteristics and advantages. Research on medicinal plants has also been carried into all aspects, such as biological traits, physiology and biochemistry, genomics, as well as differences in chemical composition, and chemical composition analysis is also involved.

Optimization of nitrogen source for enhanced production of squalene from thraustochytrid Aurantiochytrium sp.

Nitrogen (N) sources, the critical medium component, were optimized for squalene production by microalga Aurantiochytrium sp. in heterotrophic cultures. In screening experiments monosodium glutamate, yeast extract and tryptone were found to enhance cell growth and squalene production.

[Effects of space flight on protein content and electrophoresis in Glycyrrhiza uralensis].

Objective: To investigate the space environment on the role of licorice mutagenesis analysis of proteins.

Method: Licorice (Glycyrrhiza uralensis) seeds were carried by a recoverable satellite for 18 days (the average radiation dose in the flight recovery module was 0.102 m x d(-1), the orbit semidiameter 350 km, gravity 10(-6)).

[Effects of space flight on glycyrrhizic acid-related gene mutation in Glycyrrhiza uralensis].

Objective: To substantiate the effects of spaceflight on the glycyrrhizic acid-related gene mutation in Glycyrrhiza uralensis.

Method: Licorice (G. uralensis) seeds were carried by a recoverable satellite for 18 days (the average radiation dose in the flight recovery module was 0.

High-level expression, purification and characterization of a recombinant medium-temperature alpha-amylase from Bacillus subtilis.

Alpha-amylases are important industrial enzymes with a wide range of applications. Although medium-temperature alpha amylase (AmyE) has some practical advantages, its low yield has limited its applications. When an amyE gene from Bacillus subtilis BF768 was cloned into vector pWB980 and over-expressed in B.

Different survival of chromium-exposed Oxya chinensis among allozyme genotypes.

The goal of the present study was to compare the different survival of Oxya chinensis exposed to chromium(VI) among allozyme genotypes to gain a better understanding of the relationship between the genetic variations and environmental disturbance. This study analyzed the occurrence of genotypes in O. chinensis population exposed to Cr(VI).

Screening and characterization of squalene-producing thraustochytrids from Hong Kong mangroves.

Eighteen strains of thraustochytrids were newly isolated from Hong Kong mangroves, and their fatty acid and squalene contents were analyzed. All strains could grow well heterotrophically with glucose as the sole carbon source. All of them had the typical fatty acid profile of thraustchytrids and could produce a large amount of docosahexaenoic acid.