江苏菜豆同工凝集素的分离纯化及性质研究

江苏菜豆经酸水(PH2.0)抽提,硫酸铵分级沉淀,分离植物血球凝集素(PHA-P),分子量为128000的糖蛋白,活性回收率在80％以上,PHA-P经SP-sephadexc-50离子交换层析,分成L_4,L_3E_1,L_2E_2,L_1E_3,和E_4同工凝集素。 L_4和E_4等电点为5.4和6.5。亚基分子量分别是31000和33000,并有类似的氨基酸组成。PAGE分析为单一蛋白带。红细胞凝集活性随电泳迁移速度的加快而增强,促淋性细胞分裂活性则减弱。E_4血凝活性受CalNAc,EDTA抑制和Zn~(++)的促进。     

Structure of a Pancreatic ATP-Sensitive Potassium Channel

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A homogalacturonan from the radix of Platycodon grandiflorum and the anti-angiogenesis activity of poly-/oligogalacturonic acids derived therefrom

A polysaccharide, PGA4-3b, with an average molecular weight of 8.9 kDa estimated by high-performance gel-permeation chromatography (HPGPC), was isolated from radix of Platycodon grandiflorum (Jacq.) A. DC. Using monosaccharide analysis, methylation analysis and NMR spectroscopy, PGA4-3b was elucidated to be a linear poly-(1→4)-α-d-galactopyranosyluronic acid that contains no methyl ester groups. Partial acid hydrolysis of PGA4-3b yielded a series of poly- or oligogalacturonic acids with different degrees of polymerization (DP), that is, 4-3bde, 4-3bde-O-1, 4-3bde-O-2, 4-3bde-O-3, and 4-3bde-O-4. Cell tube formation inhibition tests with human microvascular endothelial cells (HMEC) for antiangiogenesis analysis showed that 4-3bde-O-1 and 4-3bde-O-2, the fractions with higher molecular weights, could inhibit tube formation, while the native PGA4-3b and low molecular weight fraction 4-3bde-O-3 and 4-3bde-O4 are ineffective. Moreover, 4-3bde-O-2 with DP 5-10 impaired cell tube formation in a dose-dependent way, suggesting its potential to be developed as an anti-angiogenesis drug. This is the first time oligogalacturonic acids are reported to show an anti-angiogenesis effect.     

A proteomic analysis of the chromoplasts isolated from sweet orange fruits [Citrus sinensis (L.) Osbeck

Here, a comprehensive proteomic analysis of the chromoplasts purified from sweet orange using Nycodenz density gradient centrifugation is reported. A GeLC-MS/MS shotgun approach was used to identify the proteins of pooled chromoplast samples. A total of 493 proteins were identified from purified chromoplasts, of which 418 are putative plastid proteins based on in silico sequence homology and functional analyses. Based on the predicted functions of these identified plastid proteins, a large proportion (～60%) of the chromoplast proteome of sweet orange is constituted by proteins involved in carbohydrate metabolism, amino acid/protein synthesis, and secondary metabolism. Of note, HDS (hydroxymethylbutenyl 4-diphosphate synthase), PAP (plastid-lipid-associated protein), and psHSPs (plastid small heat shock proteins) involved in the synthesis or storage of carotenoid and stress response are among the most abundant proteins identified. A comparison of chromoplast proteomes between sweet orange and tomato suggested a high level of conservation in a broad range of metabolic pathways. However, the citrus chromoplast was characterized by more extensive carotenoid synthesis, extensive amino acid synthesis without nitrogen assimilation, and evidence for lipid metabolism concerning jasmonic acid synthesis. In conclusion, this study provides an insight into the major metabolic pathways as well as some unique characteristics of the sweet orange chromoplasts at the whole proteome level.     

中国距水虻属四新种(双翅目,水虻科)(英文)

记述我国距水虻属Allognosta 4新种,基黑距水虻A.basinigra sp.nov.,彩旗距水虻A.caiqiana sp.nov.,大龙潭距水虻A.dalongtana sp.nov.,梁氏距水虻A.liangi sp.nov.。模式标本保存在中国农业大学昆虫博物馆。     

Determination of zeranol and its metabolites in bovine muscle and liver by a chemiluminescence enzyme immunoassay: compared to an ultraperformance liquid chromatography tandem mass spectroscopy method

A chemiluminescent enzyme immunoassay (CLEIA) was compared to an ultraperformance liquid chromatography tandem mass spectroscopy (UPLC‐MS/MS) procedure for the analysis of zeranol and its metabolites in bovine tissue samples. Apparent recoveries from fortified samples by both methods were comparable at 0.5–4.0 µg/kg and a significant correlation was obtained. For CLEIA analysis, hapten mimicking the analyte was first synthesized and conjugated with the carrier protein bovine serum albumin as the immunogen to produce monoclonal antibody. The obtained antibody showed extensive cross‐reactivity toward zeranol metabolites (zearalanone). The limit of detection of CLEIA and UPLC‐MS/MS was 0.05 µg/kg and 0.5 µg/kg, respectively. Recoveries of both methods for fortified samples were higher than 75.0% with the coefficient of variation less than 15%. These results indicated that the combination of screening with CLEIA and confirmation with UPLC‐MS/MS for zeranol and its metabolites would be a reliable method for a large number of bovine samples. Copyright © 2013 John Wiley & Sons, Ltd.     

Expression and purification of the catalytic domain of human vascular endothelial growth factor receptor 2 for inhibitor screening

Vascular endothelial growth factor (VEGF), an endothelial cell-specific mitogen, can act in tumor-induced angiogenesis by binding to specific receptors on the surface of endothelial cells. One such receptor, VEGFR-2/KDR, plays a key role in VEGF-induced angiogenesis. Here, we expressed the catalytic domain of VEGFR-2 as a soluble active kinase using Bac-to-Bac expression system, and investigated correlations between VEGFR-2 activity and enzyme concentration, ATP concentration, substrate concentration and divalent cation type. We used these data to establish a convenient, effective and non-radioactive ELISA screening technique for the identification and evaluation of potential inhibitors for VEGFR-2 kinase. We screened 200 RTK target-based compounds and identified one (TKI-31) that potently inhibited VEGFR-2 kinase activity (IC50=0.596 microM). Treatment of NIH3T3/KDR cells with TKI-31 blocked VEGF-induced phosphorylation of KDR in a dose-dependent manner. Moreover, TKI-31 dose-dependently suppressed HUVEC tube formation. Thus, we herein report a novel, efficient method for identifying VEGFR-2 kinase inhibitors and introduce one, TKI-31, that may prove to be a useful new angiogenesis inhibitor.     

浙江地区青霉素耐药肺炎链球菌PBPs基因及氨基酸序列研究

为阐明温州地区青霉素耐药肺炎链球菌（PRSP）的青霉素结合蛋白（PBPs）的基因和氨基酸序列的变异特点,对温州医学院自2000年11月～2004年1月收集的26份肺炎链球菌进行分离、鉴定及青霉素药敏实验,并对每株链球菌的PBP1A、PBP2B、PBP2X基因进行PCR扩增和直接测序,通过序列比对与生物信息学分析。结果表明,研究中的PBP1A的主要突变位点是保守基序KTG之后的4个连续氨基酸替换Thr574Ala、Ser575Thr、Gln576Gly、Phe577Tyr和保守序列STMK内的氨基酸替换Thr371Ser;PBP2B的主要突变位点是保守序列SSN之后的氨基酸替换Thr451Ala;PBP2X的主要突变位点是保守基序STMK 内的氨基酸替换Thr338Ala。以上突变类型以及菌株的青霉素耐药水平与文献报道相符。研究检测的PRSP的PBPs基因中暂未发现本地区特有的（新的）基因突变,也未检测出文献报道的某些与青霉素抗性相关的氨基酸替换。     

水生哺乳动物信标跟踪记录技术及其应用

水生哺乳动物(主要是鲸类和鳍脚类)分布范围广、活动范围大、行为复杂,且在水下活动时间长,常规的目视观察受时间和空间限制,通常只能获取有限的信。信标跟踪记录(Bio-logging)具有可跟随移动和自主操作的特征,能在很大程度上突破时间和空间限制,实时获取动物及其栖息环境信息。水生哺乳动物的信标跟踪记录始于20世纪60年代1,2,40年来,无论是记录技术,还是应用研究,都有了很大发展。2003年在日本东京国立极地研究所召开的“信标跟踪记录科学国际学术讨论会(International Symposium on Bio-loggingScience)”,收到来自法、美、英、日、澳、德、意、加、南非和中国共152名与会代表的104篇论文。这些论文主要介绍信标跟踪记录技术及其应用的现状和未来趋势。会议以不同研究对象分专题进行交流,共分为鲸类、鳍脚类、类、爬行类、鱼类和其他类6个专题,其中鸟类专题论文最多,其次是鱼类专题。有关水生哺乳动物的研究论文共22篇,除了4篇介绍记录技术外,其他论文主要介绍信标跟踪记录的应用研究,包括潜水行为、捕食策略、能量代谢、栖息地标识和发声策略研究。本文是近年来水生哺乳动物信标跟踪记录研究领域相关论文的综述,除介绍水生哺乳动物信标跟踪记录技术及其应用研究现状外,还对其不足之处和可能的发展趋势进行了讨论。此外,还重点介绍了我国珍稀动物长江江豚(Neophocaena phocaenoides as iaeorientalis)信标跟踪研究的一些进展。