Extracellular hydrolytic enzyme screening of culturable heterotrophic bacteria from deep-sea sediments of the Southern Okinawa Trough

The Southern Okinawa Trough is an area of focused sedimentation due to particulate matter export from the shelf of the East China Sea and the island of Taiwan. In order to understand the geomicrobiological characteristics of this unique sedimentary environment, bacterial cultivations were carried out for an 8.61 m CASQ core sediment sample. A total of 98 heterotrophic bacterial isolates were characterized based on 16S rRNA gene phylogenetic analysis. These isolates can be grouped into four bacterial divisions, including 13 genera and more than 20 species. Bacteria of the γ-Proteobacteria lineage, especially those from the Halomonas (27 isolates) and Psychrobacter (20 isolates) groups, dominate in the culturable bacteria assemblage. They also have the broadest distribution along the depth of the sediment. More than 72.4% of the isolates showed extracellular hydrolytic enzyme activities, such as amylases, proteases, lipases and Dnases, and nearly 59.2% were cold-adapted exoenzyme-producers. Several Halomonas strains show almost all the tested hydrolases activities. The wide distribution of exoenzyme activities in the isolates may indicate their important ecological role of element biogeochemical cycling in the studied deep-sea sedimentary environment.     

Bicyclic α,ω-dicarboxylic acid derivatives from a colonial tunicate of the family Polyclinidae

In the course of our search for bioactive metabolites from a colonial tunicate of the family Polyclinidae, six new (1–6) cyclic fatty acid derivatives were isolated. Their planar structures were established on the basis of NMR and MS spectroscopic analyses. The relative configuration was determined by NOESY experiment. Compounds 1–6 represent a fused bicyclic skeleton possibly derived from α,ω-dicarboxylic acids such as eicosanedioic acid or docosanedioic acid via a Diels–Alder type of cyclization. Compounds 1–4 and 6 showed mild cytotoxicity against a panel of five human solid tumor cell lines.     

5-N,N-Disubstituted 5-aminopyrazole-3-carboxylic acids are highly potent agonists of GPR109b

A series of 5-N,N-disubstituted-5-aminopyrazole-3-carboxylic acids were prepared and found to act as highly potent and selective agonists of the G-Protein Coupled Receptor (GPCR) GPR109b, a low affinity receptor for niacin and some aromatic d-amino acids. Little activity was observed at the highly homologous higher affinity niacin receptor, GPR109a.     

High frequency plant regeneration from the cotyledonary node of common bean

An efficient regeneration system for Phaseolus vulgaris was developed from mature seeds germinated on Murashige and Skoog (MS) medium supplemented with thidiazuron or N⁶-benzylaminopurine (BA) for 6 d. Using cotyledonary nodes, multiple buds were induced on the MS medium supplemented with 5.0 mg dm⁻³ BA with the induction frequency 71.9 % after 4-week culture. The buds were then transferred onto shoot formation medium containing 1.0 mg dm⁻³ BA, 0.1 mg dm⁻³ gibberellic acid and 2.0 mg dm⁻³ silver nitrate. The addition of AgNO₃ enhanced the frequency of the shoot formation from 61.3 to 87.6 %. Root induction medium was half-strength MS medium with 0.75 mg dm⁻³ indolebutyric acid and 0.02 mg dm⁻³ BA. The average root frequency was 84.3 %. The regenerated plantlets with healthy roots grew successfully when transferred to soil. Using this system we obtained over 10 regenerated plantlets from one explant.     

Impact of different pH control agents on biopesticidal activity of<Emphasis Type="Italic"> Bacillus thuringiensis</Emphasis> during the fermentation of starch industry wastewater

Different pH control agents (NaOH/H₂SO₄—SodSulp, NaOH/CH₃COOH—SodAcet, NH₄OH/CH₃COOH—AmmoAcet and NH₄OH/H₂SO₄—AmmoSulp) were used to investigate their effects on growth, enzyme production (alkaline protease and amylase), and entomotoxicity of Bacillus thuringiensis var. kurstaki HD-1 (Btk) against eastern spruce budworm larvae (Choristoneura fumiferana) using starch industry wastewater (SIW) as a raw material in a 15-l fermentor. AmmoSulp and SodSulp were found to be the best pH control agents for alkaline protease and amylase production, respectively; whereas, the fermented broth obtained by using SodAcet as pH control agents recorded the highest delta-endotoxin production of 1043.0 mg/l and entomotoxicity value 18.4 × 10⁹ SBU/l. Entomotoxicity of re-suspended centrifuged pellet in one-tenth of original volume in case of SodAcet as pH control agents was 26.7 × 10⁹ SBU/l and was the highest value compared to three other pH control agents.     

亚麻SRAP反应体系的优化

通过研究亚麻SRAP反应体系中主要因子对扩增结果的影响,建立了亚麻SRAP-PCR反应的优化体系.在20μL的反应体系中将PCR的5个主要成分分别设定8个浓度梯度,结果表明,最适宜的优化浓度分别为:1.5 mmol/L Mg2+、0.3 mmol/L dNTP、1.5 U Tap酶、30 ng/μL模板DNA 90 ng和25 ng/μL引物100 ng.用6个亚麻材料验证优化体系,检测结果显示,多态性高,反应体系的稳定性和可重复性好,为SRAP标记技术在亚麻分子生物学研究方面的应用奠定了基础.     

Hydra: software for tailored processing of H/D exchange data from MS or tandem MS analyses

Background  

Hydrogen/deuterium exchange mass spectrometry (H/DX-MS) experiments implemented to characterize protein interaction and protein folding generate large quantities of data. Organizing, processing and visualizing data requires an automated solution, particularly when accommodating new tandem mass spectrometry modes for H/DX measurement. We sought to develop software that offers flexibility in defining workflows so as to support exploratory treatments of H/DX-MS data, with a particular focus on the analysis of very large protein systems and the mining of tandem mass spectrometry data.     

CFTR Delivery to 25% of Surface Epithelial Cells Restores Normal Rates of Mucus Transport to Human Cystic Fibrosis Airway Epithelium

Dysfunction of CFTR in cystic fibrosis (CF) airway epithelium perturbs the normal regulation of ion transport, leading to a reduced volume of airway surface liquid (ASL), mucus dehydration, decreased mucus transport, and mucus plugging of the airways. CFTR is normally expressed in ciliated epithelial cells of the surface and submucosal gland ductal epithelium and submucosal gland acinar cells. Critical questions for the development of gene transfer strategies for CF airway disease are what airway regions require CFTR function and how many epithelial cells require CFTR expression to restore normal ASL volume regulation and mucus transport to CF airway epithelium? An in vitro model of human CF ciliated surface airway epithelium (CF HAE) was used to test whether a human parainfluenza virus (PIV) vector engineered to express CFTR (PIVCFTR) could deliver sufficient CFTR to CF HAE to restore mucus transport, thus correcting the CF phenotype. PIVCFTR delivered CFTR to >60% of airway surface epithelial cells and expressed CFTR protein in CF HAE approximately 100-fold over endogenous levels in non-CF HAE. This efficiency of CFTR delivery fully corrected the basic bioelectric defects of Cl⁻ and Na⁺ epithelial ion transport and restored ASL volume regulation and mucus transport to levels approaching those of non-CF HAE. To determine the numbers of CF HAE surface epithelial cells required to express CFTR for restoration of mucus transport to normal levels, different amounts of PIVCFTR were used to express CFTR in 3%–65% of the surface epithelial cells of CF HAE and correlated to increasing ASL volumes and mucus transport rates. These data demonstrate for the first time, to our knowledge, that restoration of normal mucus transport rates in CF HAE was achieved after CFTR delivery to 25% of surface epithelial cells. In vivo experimentation in appropriate models will be required to determine what level of mucus transport will afford clinical benefit to CF patients, but we predict that a future goal for corrective gene transfer to the CF human airways in vivo would attempt to target at least 25% of surface epithelial cells to achieve mucus transport rates comparable to those in non-CF airways.