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131.
A bleach-stable, thermotolerant, alkaline protease for detergent formulation from a newly isolated Bacillus SB5 is reported. Most (85%) activity of the enzyme was retained in the presence of 10% (v/v) H2O2 and 1% SDS (w/v) at 40°C, after 1 h. The enzyme was optimal at pH 10 and 60°C to 70°C. Enzyme activity was enhanced 30 to 80% in presence of ionic and non-ionic detergents, surfactants and commercial detergents or bleach.  相似文献   
132.
To make the native LHRH immunogenic, a multimer of LHRH interspersed with T non-B peptides (r-LHRH-d2) was expressed as recombinant protein in Escherichia coli. The expression level of the recombinant protein was around 15% of the total cellular protein and it aggregated as inclusion bodies. Inclusion bodies from the bacterial cells were isolated and purified to homogeneity. Instead of high concentrations of chaotropic agents, r-LHRH- d2 was solubilized in 50 mM citrate buffer at pH 3 containing 2 M urea. The protein was refolded by 5-fold dilution (pulsatile) with cold 10 mM citrate buffer at pH 6 in presence of 0.3 M L-arginine. Purification of r-LHRH-d2 was carried out by successive passages on CM-Sepharose column at pH 6.0 which retained extraneous proteins and pH 4.8 at which r-LHRH-d2 bound to the resin. The elution was carried out by using linear salt gradient (0.1-1 M NaCl). The overall yield of the purified r-LHRH-d2 was 40% of the initial inclusion body proteins. The purity and homogeneity were confirmed by a single homogeneous peak on analytical HPLC eluting out at 29.51 min and by single band on SDS-PAGE reactive with polyvalent anti-LHRH antibodies. Mass spectroscopic analysis indicated the protein to be of 16.6 kDa which equals the theoretically expected mass. The N-terminal amino acid analysis of r-LHRH-d2 showed the sequence which corresponded to the designed protein. The CD spectrum of the refolded r-LHRH-d2 showed that the multimer has considerable beta sheet structure like the monomeric LHRH protein.  相似文献   
133.
Vaccines capable of eliciting long-term T cell immunity are required for combating many diseases. Live vectors can be unsafe whereas subunit vaccines often lack potency. We previously reported induction of CD8(+) T cells to Ag entrapped in archaeal glycerolipid vesicles (archaeosomes). In this study, we evaluated the priming, phenotype, and functionality of the CD8(+) T cells induced after immunization of mice with OVA-Methanobrevibacter smithii archaeosomes (MS-OVA). A single injection of MS-OVA evoked a profound primary response but the numbers of H-2K(b)OVA(257-264)-specific CD8(+) T cells declined by 14-21 days, and <1% of primarily central phenotype (CD44(high)CD62L(high)) cells persisted. A booster injection of MS-OVA at 3-11 wk promoted massive clonal expansion and a peak effector response of approximately 20% splenic/blood OVA(257-264)-specific CD8(+) T cells. Furthermore, contraction was protracted and the memory pool (IL-7Ralpha(high)) of approximately 5% included effector (CD44(high)CD62L(low)) and central (CD44(high)CD62L(high)) phenotype cells. Recall response was observed even at >300 days. CFSE-labeled naive OT-1 (OVA(257-264) TCR transgenic) cells transferred into MS-OVA-immunized recipients cycled profoundly (>90%) within the first week of immunization indicating potent Ag presentation. Moreover, approximately 25% cycling of Ag-specific cells was seen for >50 days, suggesting an Ag depot. In vivo, CD8(+) T cells evoked by MS-OVA killed >80% of specific targets, even at day 180. MS-OVA induced responses similar in magnitude to Listeria monocytogenes-OVA, a potent live vector. Furthermore, protective CD8(+) T cells were induced in TLR2-deficient mice, suggesting nonengagement of TLR2 by archaeal lipids. Thus, an archaeosome adjuvant vaccine represents an alternative to live vectors for inducing CD8(+) T cell memory.  相似文献   
134.
Mycobacterium avium subspecies paratuberculosis (MAP) is the etiological agent of paratuberculosis, a chronic gastroenteritis of ruminants and has zoonotic importance. We present here a review of MAP with respect to--(i) present diagnostic techniques and important developments; and (ii) MAP strain-typing tools. A summary of the findings to date is presented, and advantages and disadvantages of each of the methods are compared and discussed.  相似文献   
135.
Awan  Sliha  Hashmi  Aisha N.  Taj  Rizwan  Munir  Sadaf  Habib  Rabia  Batool  Sajida  Azam  Maleeha  Qamar  Raheel  Nurulain  Syed M. 《Biochemical genetics》2022,60(2):720-737
Biochemical Genetics - Major depressive disorder (MDD) is characterized as clinical depression, which primarily affects the mood and behaviour of an individual. In the present study...  相似文献   
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137.
Higher fungi can rapidly produce large numbers of spores suitable for aerial dispersal. The efficiency of the dispersal and spore resilience to abiotic stresses correlate with their hydrophobicity provided by the unique amphiphilic and superior surface-active proteins–hydrophobins (HFBs)–that self-assemble at hydrophobic/hydrophilic interfaces and thus modulate surface properties. Using the HFB-enriched mold Trichoderma (Hypocreales, Ascomycota) and the HFB-free yeast Pichia pastoris (Saccharomycetales, Ascomycota), we revealed that the rapid release of HFBs by aerial hyphae shortly prior to conidiation is associated with their intracellular accumulation in vacuoles and/or lipid-enriched organelles. The occasional internalization of the latter organelles in vacuoles can provide the hydrophobic/hydrophilic interface for the assembly of HFB layers and thus result in the formation of HFB-enriched vesicles and vacuolar multicisternal structures (VMSs) putatively lined up by HFBs. These HFB-enriched vesicles and VMSs can become fused in large tonoplast-like organelles or move to the periplasm for secretion. The tonoplast-like structures can contribute to the maintenance of turgor pressure in aerial hyphae supporting the erection of sporogenic structures (e.g., conidiophores) and provide intracellular force to squeeze out HFB-enriched vesicles and VMSs from the periplasm through the cell wall. We also show that the secretion of HFBs occurs prior to the conidiation and reveal that the even spore coating of HFBs deposited in the extracellular matrix requires microscopic water droplets that can be either guttated by the hyphae or obtained from the environment. Furthermore, we demonstrate that at least one HFB, HFB4 in T. guizhouense, is produced and secreted by wetted spores. We show that this protein possibly controls spore dormancy and contributes to the water sensing mechanism required for the detection of germination conditions. Thus, intracellular HFBs have a range of pleiotropic functions in aerial hyphae and spores and are essential for fungal development and fitness.  相似文献   
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139.
极端干旱条件下燕麦垄沟覆盖系统水生态过程   总被引:2,自引:0,他引:2  
围绕极端气候条件下沟垄沟覆盖系统水文过程和水生产力变化问题开展两年的大田试验研究。以裸燕麦坝莜3号品种为材料,于2010年和2011年在甘肃定西进行,以充分灌溉为对照组,设置平地无种植、垄沟无覆膜种植、垄沟覆膜种植、裸地4个处理(此4个处理均无灌溉),测定生育期降雨、气温、0—140 cm土壤剖面水分变化、作物生长和产量等指标。结果表明,2010年和2011年分别为阶段性极端干旱和全生育期极端干旱两个类型,均导致所有处理组中土壤剖面60—100 cm的"土壤干层"现象,垄沟覆膜处理对"土壤干层"现象具有显著的缓解效应。与对照组相比,垄沟覆膜处理显著促进了收获期土壤剖面贮水量的回升,其贮水量分别提高了41.2 mm(2010年)和22.4 mm(2011年),全生育期水分利用效率和水生产力分别提高了1.7、0.4 kg·hm-2·mm-1(2010年)和6.5、9.8 kg·hm-2·mm-1(2011年)。另外,垄沟覆膜处理组的地上生物量比对照组降低了30.5%(2010年)和67.42%(2011年),但收获指数较对照分别提高了33.4%(2010年)和55.6%(2011年)。研究表明,垄沟覆膜处理促进了降水向土壤水和作物水的转化效率,显著地缓解了作物水分供需矛盾,是应对极端气候变化的重要生态策略。  相似文献   
140.
A major challenge of lipidomics is to determine and quantify the precise content of complex lipidomes to the exact lipid molecular species. Often, multiple methods are needed to achieve sufficient lipidomic coverage to make these determinations. Multiplexed targeted assays offer a practical alternative to enable quantitative lipidomics amenable to quality control standards within a scalable platform. Herein, we developed a multiplexed normal phase liquid chromatography-hydrophilic interaction chromatography multiple reaction monitoring method that quantifies lipid molecular species across over 20 lipid classes spanning wide polarities in a single 20-min run. Analytical challenges such as in-source fragmentation, isomer separations, and concentration dynamics were addressed to ensure confidence in selectivity, quantification, and reproducibility. Utilizing multiple MS/MS product ions per lipid species not only improved the confidence of lipid identification but also enabled the determination of relative abundances of positional isomers in samples. Lipid class-based calibration curves were applied to interpolate lipid concentrations and guide sample dilution. Analytical validation was performed following FDA Bioanalytical Method Validation Guidance for Industry. We report repeatable and robust quantitation of 900 lipid species measured in NIST-SRM-1950 plasma, with over 700 lipids achieving inter-assay variability below 25%. To demonstrate proof of concept for biomarker discovery, we analyzed plasma from mice treated with a glucosylceramide synthase inhibitor, benzoxazole 1. We observed expected reductions in glucosylceramide levels in treated animals but, more notably, identified novel lipid biomarker candidates from the plasma lipidome. These data highlight the utility of this qualified lipidomic platform for enabling biological discovery.  相似文献   
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