502 resultados para 7140-226


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Wasp is an important venomous animal that can induce human fatalities. Coagulopathy is a clinical symptom after massive wasp stings, but the reason leading to the envenomation manifestation is still not known. In this paper, a toxin protein is purified and characterized by Sephadex G-75 gel filtration, CM-Sephadex C-25 cationic exchange and fast protein liquid chromatography (FPLC) from the venom of the wasp, Vespa magnifica (Smith). This protein, named magnvesin. contains serine protease-like activity and inhibits blood coagulation. The cDNA encoding magnvesin is cloned from the venom sac cDNA library of the wasp. The deduced protein from the cDNA is composed of 305 amino acid residues. Magnvesin shares 52% identity with allergen serine protease from the wasp Polistes dominulus. Magnvesin exerted its anti-coagulant function by hydrolyzing coagulant factors TF, VII, VIII, IX and X. (c) 2008 Elsevier Ltd. All rights reserved.

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A 50 kDa fibrinogenolytic protease, ohagin, from the venom of Ophiophagus hannah was isolated by a combination of gel filtration, ion-exchange and heparin affinity chromatography. Ohagin specifically degraded the alpha-chain of human fibrinogen and the pr

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本发明涉及大蹼铃蟾神经营养因子及其制备方法和其基因,属于生物医学领域。其神经营养因子为从中国两栖类动物大蹼铃蟾(Bombina maxima)皮肤分泌物中分离得到的由77个氨基酸组成的一种单链多肽,分子量8125.8,等电点8.6,多肽氨基酸全序列一级结构为:AVITGACDRDVQCGSGTCCAASLWSRNIRFCVPLGNNGEECHPASHKVPYNGKRLSSLCPCKSGLTCSKSGEKFQCS。制备方法是收集大蹼铃蟾皮肤分泌物,离心去除沉淀、冷冻干燥后,经凝胶过滤、高压液相反相柱层析分离纯化后即得到。编码神经营养因子的基因由447个核苷酸组成,其中编码成熟神经营养因子为第145-375位核苷酸。其基因作为基因工程制备神经营养因子的应用。

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A novel antimicrobial peptide named odorranain-NR was identified from skin secretions of the diskless odorous frog, Odorrana grahami. It is composed of 23 amino acids with an amino acid sequence of GLLSGILGAGKHIVCGLTGCAKA. Odorranain-NR was classified into a novel family of antimicrobial peptide although it shared similarity with amphibian antimicrobial peptide family of nigrocin. Odorranain-NR has an unusual intramolecular disulfide-bridged hexapeptide segment that is different from the intramolecular disulfide-bridged heptapeptide segment at the C-terminal end of nigrocins. Furthermore, the -AKA fragment at the C-terminal of odorranain-NR is also different from nigrocins. Three different cDNAs encoding two odorranain-NR precursors and only one mature odorranain-NR was cloned from the cDNA library of the skin of O. grahami. This peptide showed antimicrobial activities against tested microorganisms except Escherichia coli (ATCC25922). Its antimicrobial mechanisms were investigated by transmission electron microcopy. odorranain-NR exerted its antimicrobial functions by various means depending on different microorganisms. (C) 2008 Elsevier Inc. All rights reserved.

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We present a new approach for estimating mixing between populations based on non-recombining markers, specifically Y-chromosome microsatellites. A Markov chain Monte Carlo (MCMC) Bayesian statistical approach is used to calculate the posterior probability

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本发明涉及大蹼铃蟾铃蟾肽及其制备方法和其基因,属于生物医学领域。其铃蟾肽为从中国两栖类动物大蹼铃蟾(Bombina maxima)皮肤分泌物中分离得到的由16个氨基酸组成的一种单链多肽,分子量1887,等电点10.6,多肽氨基酸全序列一级结构为:pEKKPPRPPQWAVGHFM-NH2。制备方法是收集大蹼铃蟾皮肤分泌物,离心去除沉淀、冷冻干燥后,经凝胶过滤、高压液相反相柱层析分离纯化后即得到。编码大蹼铃蟾铃蟾肽基因核苷酸序列由cDNA由522个核苷酸组成,其中编码成熟大蹼铃蟾铃蟾肽为第173-220位核苷酸。其基因作为基因工程制备铃蟾肽的应用。

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Two serine protease inhibitors (named BMSI 1 and BMSI 2, respectively) were identified from the skin secretions of the toad, Bombina microdeladigitora. The cDNAs encoding BMSIs were cloned from a cDNA library prepared from the toad skin. The deduced complete amino acid sequences of BMSIs indicate that mature BMSI1 and BMSI2 are composed of 60 amino acids including 10 half-cystines to form 5 disulfide bridges. A FASTA search in the databanks revealed that BMSIs exhibit sequence similarity with other serine protease inhibitors from amphibians of the genus Bombina. BMSI1 potently inhibited trypsin and thrombin with a K(i) value of 0.02 mu M and 0.15 mu M, respectively. Sequence analysis revealed that all serine protease inhibitors from five amphibians of the genus Bombina share highly conserved primary structures. (c) 2007 Elsevier Inc. All rights reserved.

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An L-amino acid oxidase from Ophiophagus hannah snake venom (Oh-LAAO) was purified by successive gel filtration, ion-exchange and heparin chromatography. Oh-LAAO did not induce platelet aggregation; however, it had potent inhibitory activity on platelet a

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本发明涉及大蹼铃蟾缓激肽及其制备方法和其基因,属于生物医学领域。其缓激肽为从中国两栖类动物大蹼铃蟾(Bombina maxima)皮肤分泌物中分离得到的由19个氨基酸组成的一种单链多肽,分子量2180,等电点11.7,多肽氨基酸全序列一级结构为:DLPKINRKGPRPPGFSPFR。制备方法是收集大蹼铃蟾皮肤分泌物,离心去除沉淀、冷冻干燥后,经凝胶过滤、高压液相反相柱层析分离纯化后即得到。编码大蹼铃蟾缓激肽基因核苷酸序列由cDNA由829个核苷酸组成,编码成熟大蹼铃蟾缓激肽为第140-196,224-280,308-364,392-448,476-532,560-616位6个核苷酸重复单元片断,从两栖类动物皮肤中得到的缓激肽基因作为基因工程制备缓激肽的应用。

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By Sephadex G-50 gel filtration, Resource Q anionic exchange and C4 reversed phase liquid high performance liquid chromatography, a proteinase inhibitor protein (Ranaserpin) was identified and purified from the eggs of the odour frog, Rana grahami. The protein displayed a single band adjacent to the molecular weight marker of 14.4 kDa analyzed by SDS-PAGE. The inhibitor protein homogeneity and its molecular weight were confirmed again by MALDI-TOF mass spectrometry analysis. The MALDI-TOF mass spectrum analysis gave this inhibitor protein an m/z of 14422.26 that was matched well with the result from SDS-PAGE. This protein is a serine proteinase inhibitor targeting multiple proteinases including trypsin, elastase, and subtilisin. Ranaserpin inhibited the proteolytic activities of trypsin, elastase, and subtilisin. It has an inhibitory constant (K-i) of 6.2 x 10(-8) M, 2.7 x 10(-7) M and 2.2 x 10(-8) M for trypsin, elastase, and subtilisin, respectively. This serine proteinase inhibitor exhibited bacteriostatic effect on Gram-positive bacteria Bacillus subtilis (ATCC 6633). It was suggested that ranaserpin might act as a defensive role in resistance to invasion of pests or pathogens. This is the first report of serine proteinase inhibitor and its direct defensive role from amphibian eggs. (C) 2007 Elsevier Inc. All rights reserved.

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Three cDNA sequences coding for elapid cathelicidins were cloned from constructed venom gland cDNA libraries of Naja atra, Bungarus fasciatus and Ophiophagus hannah. The open reading frames of the cloned elapid cathelicidins were all composed of 576 bp an

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本发明涉及无指盘臭蛙胰岛素释放促进因子和在制药中的应用,属于生物医学技术领域。本发明通过常规的生物化学手段,从无指盘臭蛙皮肤分泌液中分离纯化得到胰岛素释放促进因子肽并测定其序列,按照所得的序列合成该多肽。无指盘臭蛙胰岛素释放促进因子是一种单链多肽,分子量2648.4道尔顿,等电点 9.70,多肽全序列为:苯丙氨酸-亮氨酸-脯氨酸-亮氨酸-亮氨酸-丙氨酸- 甘氨酸-亮氨酸-丙氨酸-丙氨酸-天冬酰胺-苯丙氨酸-亮氨酸-脯氨酸- 赖氨酸-亮氨酸-苯丙氨酸-半胱苷酸-赖氨酸-异亮氨酸-苏氨酸-赖氨酸 -赖氨酸-半胱苷酸。本发明具有很好的促进胰岛素释放的作用,同时还具有无溶血活性、无血浆凝固活性等优点,可作为制备治疗糖尿病药物的应用。

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Horseflies are economically important blood-feeding arthropods and also a nuisance for humans and vectors for filariasis. They rely heavily on the pharmacological properties of their saliva to get a blood meal and suppress immune reactions of hosts. Little information is available on antihemostatic substances in horsefly salivary glands; especially no horsefly immune suppressants have been reported. By proteomics or peptidomics and coupling transcriptome analysis with pharmacological testing, several families of proteins or peptides, which act mainly on the hemostatic system or immune system of the host, were identified and characterized from 30,000 pairs salivary glands of the horsefly Tabanus yao (Diptera, Tabanidae). They are: (i) a novel family of inhibitors of platelet aggregation including two members, which possibly inhibit platelet aggregation by a novel mechanism and act on platelet membrane, (ii) a novel family of immunosuppressant peptides including 12 members, which can inhibit interferon-gamma production and increase interleukin-10 secretion, (iii) a serine protease inhibitor with 56 amino acid residues containing anticoagulant activity, (iv) a serine protease with anticoagulant activity, (v) a protease with fibrinogenolytic activity, (vi) three families of antimicrobial peptides including six members, (vii) a hyaluronidase, (viii) a vasodilator peptide, which is an isoform of vasotab identified from Hybomitra bimaculata, and interestingly (ix) two metallothioneins, which are the first metallothioneins reported from invertebrate salivary glands. The current work will facilitate the understanding of the molecular mechanisms of the ectoparasite-host relationship and help in identifying novel vaccine targets and novel leading pharmacological compounds.

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Snake venom Kunitz/BPTI members are good tools for understanding of structure-functional relationship between serine proteases and their inhibitors. A novel dual Kunitz/BPTI serine proteinase inhibitor named OH-TCI (trypsin- and chymotrypsin-dual inhibito

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本发明涉及一种无指盘臭蛙蛙皮肽及其基因和在制药中的应用,属于生物医学领域。该活性多肽是中国两栖类动物无指盘臭蛙基因编码的一种单链多肽,分子量3355.95道尔顿,等电点10.14,多肽全序列一级结构为: Gly Leu Gly Gly Ala Lys Lys Asn Phe Ile Ile Ala Ala Asn Lys Thr Ala Pro Gln Ser Val Lys Lys Thr Phe Ser Cys Lys Leu Tyr Asn Gly。编码无指盘臭蛙蛙皮肽的基因由 731个核苷酸组成,其中编码成熟无指盘臭蛙蛙皮肽为第520-616位核苷酸。人工合成的无指盘臭蛙蛙皮肽具有显著的抑制细菌和真菌生长的作用,可以作为制备病原微生物感染疾病的治疗药物被应用。本发明的无指盘臭蛙蛙皮肽具有结构简单、人工合成方便、抗菌谱系广的有益特点。