Bioinformatics Analysis of Bone Morphogenetic Protein 4 (BMP4) of Sheep

The assay was aimed to explore the biological characteristics of bone morphogenetic protein 4 (BMP4) of sheep,NCBI,DNAMAN DNAStar,TMHMM Server v.2.0,PsortⅡ,SignalP various bioinformatical softwares were used to speculate the physical and chemical properties,hydrophobic property,phosphorylation site,conservative structure domain,protein secondary structure of BMP4 protein.Also,the three-dimensional structure was forecasted with the SWISS-MODEL Workspace software.The results indicated that the BMP4 of sheep had high homologies with the BMP4 of various species.The encoded protein was a hydrophilic protein which was unstable.There was no transmembrane regions and it was likely to be located in the nucleus.What was more,there was signal peptide and eighteen phosphorylation sites.Through the forecast of functional domains,the protein had two functional domains,including the transforming growth factor-beta (TGF-beta) superfamily and TGF-beta propeptide superfamily.The result was consistent with the function of BMP4 gene family,it also demonstrated that BMP4 was a growth factor and it had the function of signal transduction.The amino acid homology between the predicted 3D structure of protein and template 3bmp.1.A was 88.29%.The bioinformatics analysis of BMP4 gene could provide reference for the further study in practice.     

大鼠成熟的肺表面活性蛋白B的原核表达及纯化

为表达和纯化SP-B蛋白,先对SP-B基因进行稀有密码子优化,PCR反应获得SP-B片段,构建重组质粒pGEX4T-1/SP-B,转化到E.coli BL21(DE3)中诱导表达;用SDS-PAGE与Western blot进行检测;用GSTPrep FF 16/10对融合蛋白进行纯化。经双酶切鉴定证实质粒中插入基因长250bp,测序结果与大鼠SP-B cDNA序列相符;质粒转化后用IPTG进行诱导,在分子质量约34ku处出现1个新条带,与pGEX4T-1/SP-B蛋白预期大小一致,且该融合蛋白能可溶性表达并被纯化。结果表明成功构建了pGEX4T-1/SP-B重组质粒,表达、纯化得到GST/SP-B蛋白,为研究肺表面活性物质替代药物奠定了基础。     

港口原油装船VOCs大气环境影响探讨

收集了原油装船VOCs的估算方法，认为原油装船时VOCs排放量为0.012％，VOCs浓度为0.1kg／m3。采用SCREEN3对其环境影响进行分了析，结果表明：下风向最大浓度出现在400m 处，浓度值7.99mg／m3，直到2700m处，浓度值才小于1mg／m3，直到10000m处，浓度值仍为0.14mg／m3，原油装船VOCs的大气环境影响较大。     

Can additional N fertiliser ameliorate the elevated CO2‐induced depression in grain and tissue N concentrations of wheat on a high soil N background?

Elevated CO₂ stimulates crop yields but leads to lower tissue and grain nitrogen concentrations [N], raising concerns about grain quality in cereals. To test whether N fertiliser application above optimum growth requirements can alleviate the decline in tissue [N], wheat was grown in a Free Air CO₂ Enrichment facility in a low‐rainfall cropping system on high soil N. Crops were grown with and without addition of 50–60 kg N/ha in 12 growing environments created by supplemental irrigation and two sowing dates over 3 years. Elevated CO₂ increased yield and biomass (on average by 25%) and decreased biomass [N] (3%–9%) and grain [N] (5%). Nitrogen uptake was greater (20%) in crops grown under elevated CO₂. Additional N supply had no effect on yield and biomass, confirming high soil N. Small increases in [N] with N addition were insufficient to offset declines in grain [N] under elevated CO₂. Instead, N application increased the [N] in straw and decreased N harvest index. The results suggest that conventional addition of N does not mitigate grain [N] depression under elevated CO₂, and lend support to hypotheses that link decreases in crop [N] with biochemical limitations rather than N supply.     

进口大豆粉碎细度对索氏抽提法测粗脂肪含量的影响

以进口大豆为研究对象,采用高效粉碎机和脂肪测定仪进行粉碎和抽提,研究其粉碎细度对索氏抽提法测粗脂肪含量的影响。结果表明,大豆粉碎细度越小,其粗脂肪含量测得越高。     

苦瓜对白粉病的抗性与相关生理生化指标的关系

为探讨苦瓜抗白粉病的生理生化机制,以对白粉病不同抗性的4个苦瓜品系为材料,研究苗期感染白粉病菌后,苦瓜叶片生理生化指标的变化。结果表明:接种后,叶绿素和可溶性蛋白质量分数均呈先上升后降低的趋势;可溶性糖质量分数呈下降-上升-下降-上升的趋势;抗病品系的可溶性糖、叶绿素质量分数和过氧化物酶(POD)、多酚氧化酶(PPO)活性均高于或显著高于感病品系和高感品系;抗病品系的抗坏血酸(AsA)质量分数的上升和下降的幅度均小于感病品系和高感品系;接种后10~20d,抗坏血酸过氧化物酶(APX)活性表现为抗病品系感病品系高感品系。叶绿素、可溶性糖质量分数和POD、PPO活性与病情指数呈显著或极显著负相关。综上说明,白粉病菌侵染苦瓜后,抗病品系可通过保持较高的叶绿素质量分数,增加可溶性糖、可溶性蛋白、AsA质量分数及增强POD、PPO、APX活性来提高抗病性。叶绿素、可溶性糖质量分数和POD、PPO活性均可作为苦瓜对白粉病抗性早期鉴定的指标。     

重组猪抑制素蛋白质中毒素残留检测及其理化稳定性

为探索纯化的重组猪抑制素蛋白质毒素残留情况以及重组猪抑制素蛋白质稳定性,本研究利用鲎试剂、气相色谱和SDS-PAGE方法对重组猪抑制素蛋白质中的细菌内毒素、β-巯基乙醇的残留量及其蛋白质在不同温度、极端p H值和反复冻融条件下的稳定性进行检测。结果显示,经过3次等电点沉淀洗涤后,重组猪抑制素蛋白质中细菌内毒素和β-巯基乙醇的残留量大幅减少。通过在不同温度下的处理发现,重组猪抑制素蛋白质在4℃环境下较稳定,可以长期保存;但在37℃时,稳定性快速下降,随着温度上升而降解加速。通过极端p H值和反复冻融试验发现,重组猪抑制素蛋白质对极端p H值和反复冻融具有较好的耐受性。     

酸奶营养品质提升的加工工艺研究

牛奶中含有丰富的活性营养物质,包括乳铁蛋白、免疫球蛋白、乳过氧化物酶、α-乳白蛋白、β-乳球蛋白等。传统工艺生产的酸奶经过高温杀菌,活性营养物质几乎完全损失。为了避免这一情况,本文推出一种新的酸奶生产工艺,生产出的酸奶可保留大部分活性营养物质。首先将牛奶的乳脂进行分离,乳脂部分进行125 ℃、5 s杀菌,脱脂牛奶部分进行75 ℃、15 s杀菌,将两部分料液混合后加入菌种发酵至酸度75~85°T,破乳后冷却后熟8 h以上。经测定,新工艺酸奶中α-乳白蛋白、β-乳球蛋白、乳铁蛋白、免疫球蛋白、乳过氧化物酶含量分别为966 mg/L、1 963 mg/L、23.4 mg/L、102 mg/L、1 025 U/L,远高于传统工艺酸奶的68 mg/L、200 mg/L、0.7 mg/L、14 mg/L、0 U/L。通过对比新工艺与传统工艺酸奶保质期内的活菌数、黏度、酸度和口感,并无显著差异。