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921.
922.
E. S. Pojidaeva S. Malterer A. S. Baik A. V. Sokolenko 《Russian Journal of Plant Physiology》2013,60(4):511-517
The genome of cyanobacterium Synechocystis sp. PCC 6803 contains the sll0136 (pepP) gene encoding the putative homolog of proline aminopeptidase PII (AMPPII) of the heterotrophic bacterium Escherichia coli. AMPPII is known to cleave the N-terminal amino acid residue of peptides and proteins only in the case of a penultimate proline position. The Synechocystis sp. PCC 6803 insertion mutant with inactivated pepP gene is characterized by the reduced content of phycobiliproteins and also proteins of photosystem II, which may be related to the reduced synthesis or stability of corresponding proteins. A possible involvement of PepP in biogenesis of proteins of the photosynthetic apparatus is discussed. 相似文献
923.
Julie Brault Ronald J. Meis Linhong Li Ezekiel Bello Taylor Liu Colin L. Sweeney Sherry M. Koontz Kennichi Dowdell Narda Theobald Janet Lee Cornell Allen Aaron B. Clark Juan C. Ravell Michael J. Lenardo Gary A. Dahl Harry L. Malech Suk See De Ravin 《Cytotherapy》2021,23(3):203-210
Background aimX-linked MAGT1 deficiency with increased susceptibility to EBV-infection and N-linked glycosylation defect' (XMEN) disease is caused by mutations in the magnesium transporter 1 (MAGT1) gene. Loss of MAGT1 function results in a glycosylation defect that abrogates expression of key immune proteins such as the NKG2D receptor on CD8+ T and NK cells, which is critical for the recognition and killing of virus-infected and transformed cells, a biomarker for MAGT1 function. Patients with XMEN disease frequently have increased susceptibility to EBV infections and EBV-associated B cell malignancies, for which no specific treatment options are currently available. Experimental transfer of donor EBV-specific cytotoxic T cells may be beneficial but carries the risks of eliciting alloimmune responses. An approach for cell therapy to address viral infections and associated complications that avoids the risks of alloimmunity is needed.MethodsHere the authors assess the feasibility and efficiency of correcting autologous lymphocytes from XMEN patients by MAGT1 mRNA electroporation (EP) that avoids genomic integration and can be scaled for clinical application.Results and conclusionsRestoration of NKG2D expression was demonstrated in XMEN patient lymphocytes after MAGT1 mRNA electroporation that reach healthy donor levels in CD8+ T and NK cells at 1-2 days after EP. NKG2D expression persisted at ~50% for 2 weeks after EP. Functionally, mRNA-correction of XMEN NK cells rescued cytotoxic activity also to healthy donor NK cell level. The restored NKG2D receptor expression and function were unaffected by cryopreservation, which will make feasible repeat infusions of MAGT1 mRNA-corrected autologous XMEN CD8+ T and NK cells for potential short term therapy for XMEN patients without the risks of alloimmunization. 相似文献
924.
Heeyoung Park Sang Un Park Byeong‐Kwan Jang Jeong Jae Lee Yong Suk Chung 《Global Change Biology Bioenergy》2021,13(1):201-210
Kenaf (Hibiscus cannabinus) is an annual fiber crop grown mainly in India and China. This crop is becoming a new bio‐based energy source because of its fast growth rate, excellent CO2 absorption ability, and large productivity per unit area. In this study, we evaluated 10 different cultivars of kenaf for their potential as biomass for cellulosic ethanol production. First, kenaf samples were hydrolyzed using dilute sulfuric acid, which is the most simple and cost‐effective pretreatment method. Next, simultaneous saccharification and fermentation (SSF) of the hydrolysates were performed by wild‐type and engineered xylose‐fermenting yeast strains. The results of compositional analysis of the biomass, the hydrolysates, and the fermented products suggested that ethanol yield and productivity were significantly affected by a type of kenaf cultivars, which was not predictable based on the biomass compositions. Also, the ethanol production was maximized when the xylose fraction was utilized by engineered yeast under the control of pH to avoid acetate inhibition. Considering the sugar compositions and their fermentability, kenaf can be a promising energy‐dedicated crop for cellulosic ethanol production. 相似文献
925.
Tuyen V. Ha Wonkook Kim Thang Nguyen-Tien Johanna Lindahl Hung Nguyen-Viet Nguyen Quang Thi Huy Van Nguyen Fred Unger Hu Suk Lee 《PLoS neglected tropical diseases》2021,15(6)
Japanese encephalitis (JE) is the major cause of viral encephalitis (VE) in most Asian-Pacific countries. In Vietnam, there is no nationwide surveillance system for JE due to lack of medical facilities and diagnoses. Culex tritaeniorhynchus, Culex vishnui, and Culex quinquefasciatus have been identified as the major JE vectors in Vietnam. The main objective of this study was to forecast a risk map of Culex mosquitoes in Hanoi, which is one of the most densely populated cities in Vietnam. A total of 10,775 female adult Culex mosquitoes were collected from 513 trapping locations. We collected temperature and precipitation information during the study period and its preceding month. In addition, the other predictor variables (e.g., normalized difference vegetation index [NDVI], land use/land cover and human population density), were collected for our analysis. The final model selected for estimating the Culex mosquito abundance included centered rainfall, quadratic term rainfall, rice cover ratio, forest cover ratio, and human population density variables. The estimated spatial distribution of Culex mosquito abundance ranged from 0 to more than 150 mosquitoes per 900m2. Our model estimated that 87% of the Hanoi area had an abundance of mosquitoes from 0 to 50, whereas approximately 1.2% of the area showed more than 100 mosquitoes, which was mostly in the rural/peri-urban districts. Our findings provide better insight into understanding the spatial distribution of Culex mosquitoes and its associated environmental risk factors. Such information can assist local clinicians and public health policymakers to identify potential areas of risk for JE virus. Risk maps can be an efficient way of raising public awareness about the virus and further preventive measures need to be considered in order to prevent outbreaks and onwards transmission of JE virus. 相似文献
926.
Yin Ji Piao So-Hyun Yoon Hoe Suk Kim Woo Kyung Moon Wonshik Han 《Biochemistry and Biophysics Reports》2021
We here evaluated the therapeutic effect of tumor cell-derived exosomes (TEXs)-stimulated dendritic cells (DCs) in a syngeneic orthotopic breast tumor model. The DC line DC2.4 and breast cancer cell line E0771 originally isolated from C57BL/6 mice were used. E0771 cells stably expressing the exosomal CD63-RFP or luciferase (Luc) and DC2.4 cells stably expressing GFP were produced using lentivirus. TEXs were purified from conditioned medium of E0771/CD63-RFP cells. Breast tumor model was established by injecting E0771/Luc cells into mammary gland fat pad of mice. TEXs contained immune modulatory molecules such as HSP70, HSP90, MHC I, MHC II, TGF-β, and PD-L1. TEXs were easily taken by DC2.4 cells, resulting in a significant increase in the in vitro proliferation and migration abilities of DC2.4 cells, accompanied by the upregulation of CD40. TEX-DC-treated group exhibited a decreased tumor growth compared with control group. CD8+ cells were more abundant in the tumors and lymph nodes of TEX-DC-treated group than in those of control group, whereas many CD4+ or FOXP3+ cells were localized in those of control group. Our results suggest a potential application of TEX-DC-based cancer immunotherapy. 相似文献
927.
Moon-Soo Chung Ping Huang Chan Man Ha Ji Hyung Jun Sung-Ju Ahn Fu-chun Zhang Hyun-Jong Bae Baik Ho Cho Cheol Soo Kim 《Journal of Plant Biology》2011,54(1):57-64
We carried out functional analysis of a putative novel Arabidopsis plasma membrane glucose-responsive regulator, designated AtPGR, which contains seven predicted transmembrane domains. Several
evidences showed that AtPGR is a glucose-related protein, but its biological functions have yet to be reported in any plant.
Analyses of the AtPGR promoter-β-glucuronidase (GUS) construct and RNA in situ hybridization revealed substantial gene expression in the vasculature
of various tissues, especially in the phloem region. Glucose treatment induced the highest levels of GUS activity, reaching
a peak at 3 h and declining thereafter, consistent with glucose-mediated regulation of the AtPGR promoter. We generated an atpgr RNAi knockdown mutant and found that this plant grew and developed normally. Ectopic expression of AtPGR gene modulated the induction of glucose and 2-deoxyglucose insensitivity under stress conditions. By way of contrast, cotyledon
greening of atpgr RNAi knockdown mutant seeds enhanced sensitivity to glucose and 2-deoxyglucose. Taken together, these results suggest that
AtPGR functions as a potential glucose-responsive regulator in carbohydrate metabolism. 相似文献
928.
929.
Transesterification using the cross-linked enzyme aggregate of Photobacterium lipolyticum lipase M37
Biodiesel is methyl and ethyl esters of long-chain fatty acids produced from vegetable oils or animal fats. Lipase enzymes have occasionally been used for the production of this biofuel. Recently, biodiesel production using immobilized lipase has received increased attention. Through enhanced stability and reusability, immobilized lipase can contribute to the reduction of the costs inherent to biodiesel production. In this study, methanol-tolerant lipase M37 from Photobacterium lipolyticum was immobilized using the cross-linked enzyme aggregate (CLEA) method. Lipase M37 has a high lysine content (9.7%) in its protein sequence. Most lysine residues are located evenly over the surface of the protein, except for the lid structure region, which makes the CLEA preparation yield quite high (~93%). CLEA M37 evidences an optimal temperature of 30oC, and an optimal pH of 9-10. It was stable up to 50°C and in a pH range of 4.0-11.0. Both soluble M37 and CLEA M37 were stable in the presence of high concentrations of methanol, ethanol, 1-propanol, and nbutanol. That is, their activities were maintained at solvent concentrations above 10% (v/v). CLEA M37 could produce biodiesel from olive oil and alcohols such as methanol and ethanol. Additionally, CLEA M37 generated biodiesel via both 2-step methanol feeding procedures. Considering its physical stability and reusability, CLEA M37 may potentially be used as a catalyst in organic synthesis, including the biodiesel production reaction. 相似文献
930.
Hwang IY Lim SK Ku HO Park CK Jung SC Park YH Nam HM 《Journal of microbiology and biotechnology》2011,21(12):1352-1355
Forty-one Enterococcus faecalis (E. faecalis) isolates from feces of pigs and chickens in Korea were screened for the presence of virulence factors. Gelatinase activity (85.4%, 35/41) was the more commonly observed phenotype of virulence in E. faecalis, compared with hemolytic activity (12.2%, 5/41). Thirty-one of 35 (88.6%) gelatinase-positive E. faecalis isolates harbored the gelE and fsrABC genes. A gene encoding for the enterococcal surface protein (Esp) was detected in 24.4% (10/41) of the isolates. All betahemolysin- producing isolates harbored the esp gene. 相似文献