The chimeric cytokine Hyper-IL-6 enhances the efficiency of lentiviral gene transfer in hepatocytes both in vitro and in vivo

Lentiviral vectors have been used for gene transfer into the liver but their ability to efficiently transduce quiescent hepatocytes remains controversial. Lentivirus-mediated gene transfer is more efficient in cycling cells. We determine the effect of H-IL6 in the lentiviral transduction. The lentiviral vector was used to transduce HepG2 cells and mice liver cells, previously treated with H-IL6. The highest transduction level was observed in HepG2 cells treated with 30 ng/mL H-IL6 and in the mice that received 4 μg H-IL6. Our results suggest that H-IL6 is an inducer of lentiviral gene transfer into the liver cells without any toxicity.     

Sortase-mediated protein ligation: an emerging biotechnology tool for protein modification and immobilisation

Sortases are transpeptidases produced by Gram-positive bacteria to anchor cell surface proteins covalently to the cell wall. The Staphylococcus aureus sortase A (SrtA) cleaves a short C-terminal recognition motif (LPXTG) on the target protein followed by the formation of an amide bond with the pentaglycine cross-bridge in the cell wall. Over recent years, several researchers have exploited this specific reaction for a range of biotechnology applications, including the incorporation of non-native peptides and non-peptidic molecules into proteins, the generation of nucleic acid–peptide conjugates and neoglycoconjugates, protein circularisation, and labelling of cell surface proteins on living cells.     

The effect of jasmonic acid on the accumulation of ABA,proline and spermidine and its influence on membrane injury under water deficit in two barley genotypes

Seedlings of two barley genotypes (‘Maresi’ and wild form of Hordeum spontaneum) were treated with jasmonic acid (JA 5 μM and 15 μM) for 24 h, and then subjected to water stress (PEG 6000 solution of − 1.5 MPa). JA caused an increase in the content of ABA but not in that of proline and spermidine in the two studied genotypes. The effect of the treatment did not depend on the applied JA concentration. The pre-stress treatment with JA changed plant response to water deficit with regard to membrane injury. Treatment with a lower JA concentration (5 μM) caused a substantial reduction of the stress-induced membrane damage in the both genotypes. A higher JA concentration (15 μM) caused the reduction of membrane injury only in H. spontaneum and was ineffective in ‘Maresi’. JA had no influence on the leaf water status in water-stressed plants. A possible role of JA in leaf ABA accumulation and alleviation of cell membrane injury under water deficit is discussed. The work was partly supported by the Polish Committee For Scientific Research, grant No 5 PO6A 036 18     

Molecular diversity of 1-aminocyclopropane-1-carboxylate (ACC) deaminase producing PGPR from wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.) rhizosphere

Aims

The present study was planned to investigate the diversity of 1-aminocyclopropane-1-carboxylate (ACC) deaminase producing bacteria from the rhizosphere of wheat plants and subsequent evaluation of selected PGPR on growth enhancement of wheat seedlings under drought and saline conditions.

Methods

ACC deaminase producing plant growth promoting rhizobacteria (PGPR) were isolated from the rhizosphere of wheat and identified using 16S rRNA gene sequence analysis. Isolates were evaluated for various direct and indirect plant growth promoting (PGP) traits. Plant inoculation experiment was conducted using isolates IG 19 and IG 22 in wheat to assess their plant growth promotion potential under salinity and drought stress.

Results

Thirty-eight ACC deaminase producing PGPR were isolated which belonged to 12 distinct genera and falling into four phyla γ-proteobacteria, β-proteobacteria, Flavobacteria and Firmicutes. Klebsiella sp. was the most abundant genera and followed by Enterobacter sp. The isolates exhibited ACC deaminase activities ranging from 0.106–0.980 μM α- ketobutyrate μg protein^?1 h^?1. The isolates showed multiple PGP traits such as IAA production, phosphate, zinc, potassium solubilization and siderophore production. Enterobacter cloacae (IG 19) and Citrobacter sp. (IG 22) inoculated wheat seedlings showed notable increases in fresh and dry biomass under non-stress as well as under stressed condition.

Conclusion

To the best of our knowledge this is the first report of presence of ACC deaminase activity and other PGP traits from the genus Citrobacter and Empedobacter. Our finding revealed that the γ-proteobacteria group dominated the wheat rhizosphere. Plant inoculation with PGPR could be a sustainable approach to alleviate abiotic stresses in wheat plants. These native PGPR isolates could be used as potential biofertilizers for sustainable agriculture.

     

Production of β-xylosidase from <Emphasis Type="Italic">Trichoderma asperellum</Emphasis> KIF125 and its application in efficient hydrolysis of pretreated rice straw with fungal cellulase

On-site cellulase and hemicellulase production is a promising way to reduce enzyme cost in the commercialization of the lignocellulose-to-ethanol process. A hemicellulase-producing fungal strain suitable for on-site enzyme production was selected from cultures prepared using wet disc-milling rice straw (WDM-RS) and identified as Trichoderma asperellum KIF125. KIF125 hemicellulase showed uniquely high abundance of β-xylosidase in the xylanolytic enzyme system compared to other fungal hemicellulase preparations. Supplementation of Talaromyces cellulolyticus cellulase with KIF125 hemicellulase was more effective than that with the hemicellulases from other fungal sources in reducing the total enzyme loading for the improvement of xylose yield in the hydrolysis of ball-milling RS, due to its high β-xylosidase dominance. β-Xylosidase in KIF125 hemicellulase was purified and classified as a glycosyl hydrolase family 3 enzyme with relatively high specificity for xylobiose. The production of KIF125 β-xylosidase in the fermentor was estimated as 118 U/g-WDM-RS (2350 U/L culture) at 48 h. These results demonstrate that KIF125 is promising as a practical hemicellulase source to combine with on-site cellulase production using T. cellulolyticus.     

Comparison of three ELISA kits for the differentiation of foot-and-mouth disease virus-infected from vaccinated animals

A study was performed to validate 3 FMDV 3ABC-I-ELISA kits developed in China for the differentiation of FMDV infected and vaccinated animals. Sets of sera from naive and vaccinated cattle as well as from cattle that had been infected were tested for antibodies against nonstructural proteins (NSPs) of FMDV by commercial diagnosis kits, Ceditest® FMDV-NS (Ceditest® kit), UBI® FMDV NONSTRUCTURAL PROTEIN ELISA DIRECTION INSERT (UBI® kit) and a FMDV 3ABC-I-ELISA kit developed at the Lanzhou Veterinary Research Institute. The test parameters (sensitivity and specificity) of the three kits were determined, and the result obtained from FMD 3ABC-I-ELISA kit was compared with that obtained from two foreign kits. The results indicated that the coincidence rate between the FMDV 3ABC-I-ELISA and Ceditest® kits was 98.05%, and the coincidence rate between the FMDV 3ABC-I-ELISA and UBI® kits was 94.4%; the sensitivity of both Ceditest® and FMDV 3ABC-I-ELISA kit was 100%. However, the sensitivity of the UBI® kit was only 81.8%. With sera from naive or vaccinated non-infected animals, the specificity of all tests exceeded 90%.     

免疫信号轴揭示水稻与病原菌斗争的秘密

近年,我国学者在水稻(Oryza sativa)广谱抗病机制、抗性与产量协调机制等方向的研究取得了一系列突破性进展。最近,何祖华和杨卫兵团队在水稻抗病性研究中再次取得突破,发现1个以钙感应蛋白ROD1和过氧化氢酶CatB为核心的信号轴,通过负调控水稻免疫反应,保证正常生长条件下维持低水平的免疫反应,促进水稻正常生长发育...     

代谢型谷氨酸受体在突触可塑性中的作用研究进展

突触可塑性是近 30年来神经科学领域的研究热点之一 ,它主要包括长时程增强 (long termpotentiation ,LTP)和长时程抑制 (long termdepression ,LTD)。以往的研究已经证实 ,离子型谷氨酸受体 (iGluRs)中的NMDA受体和AMPA受体 ,在LTP和LTD的诱导和维持中通过阳离子内流 ,引起细胞内的级联反应而起作用。新近的研究发现 ,代谢型谷氨酸受体 (mGluRs)与G蛋白偶联 ,通过细胞内的多种信使系统介导慢突触传递。本文主要就mGluRs在不同脑区LTP和LTD中的作用进行综述     

A modified Coomassie Brilliant Blue staining method at nanogram sensitivity compatible with proteomic analysis

A more sensitive and convenient Coomassie Brilliant Blue (CBB) staining method for visualizing proteins was developed. Compared with the modifications include the supplement of 10% (v/v) methanol into the fixing solution, an increase of an additional sensitization step and CBB raised from 0.1 to 0.125%. The improved method can detect proteins at nanogram level. The improved method is more sensitive than Blue Silver and more convenient than the Silver protocol. Mass spectrometry results confirmed that it is suitable for subsequent proteomic research.     

Chondroitin sulfates and their binding molecules in the central nervous system

Chondroitin sulfate (CS) is the most abundant glycosaminoglycan (GAG) in the central nervous system (CNS) matrix. Its sulfation and epimerization patterns give rise to different forms of CS, which enables it to interact specifically and with a significant affinity with various signalling molecules in the matrix including growth factors, receptors and guidance molecules. These interactions control numerous biological and pathological processes, during development and in adulthood. In this review, we describe the specific interactions of different families of proteins involved in various physiological and cognitive mechanisms with CSs in CNS matrix. A better understanding of these interactions could promote a development of inhibitors to treat neurodegenerative diseases.