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1.
A bradykinin-potentiating peptide has been isolated from the venom of the spiderLatrodectus tredecimguttatus. Its physicochemical properties and amino acid composition have been investigated in detail. It has been shown by biological testing on isolated neck of the rat uterus that the peptide increases the contractile effect of bradykinin in in vitro experiments. The potentiating unit is 2 · 10–3 mg/ml. A 50% increase in the hypotensive effect of bradykinin at a concentration of the bradykinin-potentiating peptide of 15 µg/kg of body weight has been found, the increase in the intensity of the effect being accompanied by a prolongation of its action.A. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 699–703, September–October, 1989.  相似文献   

2.
An affinity method is decribed for isolating -latrotoxin, a neurotoxin with a presynaptic action from the venom of the spiderLatrodectus tredecimguttatus, by two different antibody immunosorbents enabling the neurotoxin to be obtained in the homogeneous state according to the result of immunoelectrophoresis and electrophoresis in polyacrylamide gel after one chromatographic isolation. The first immunosorbent consisted of monospecific antibodies to -latrotoxin bound to the Fc fragment of protein of protein A fromStaphylococcus aureus which, in its turn, was covalently conjugated with a cellulose sorbent — Tsellopor; and the second consisted of the active Fab fragments of the same antibodies covalently conjugated with Tsellopor. It was shown that the capacity of the Fab-Tsellopor immunosorbent was 1.5–2.0 times higher than the capacity of the antibody-protein A-Tsellopor immunosorbent.A. S. Sadykov Institute of Bioorganic Chemistry, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 679–682, September–October, 1988.  相似文献   

3.
Ribosomally produced peptides that contain D-amino acids have been isolated from a number of vertebrate and invertebrate sources. In each case, the D-amino acids are introduced by a posttranslational modification of a parent peptide containing only amino acids of the L-configuration. The only known enzyme to catalyze such a reaction is the peptide epimerase (also known as peptide isomerase) from the venom of the funnel web spider, Agelenopsis aperta. This enzyme interconverts two 48-amino-acid-long peptide toxins that differ only by the stereochemistry at a single serine residue. In this paper we report the synthesis and testing of two pentapeptide analogues that contain modified amino acids at the site normally occupied by the substrate serine residue. When the L-chloroalanine-containing peptide 3 was incubated with the epimerase it was converted into the dehydroalanine-containing peptide 4 via an elimination of HCl. The dehydroalanine peptide 4 was independently synthesized and found to act as a potent inhibitor of the epimerase (IC50 = 0.5 microM). These results support a direct deprotonation/reprotonation mechanism in which a carbanionic intermediate is formed. The observed inhibition by 4 can be attributed to the sp(2)-hybridization of the alpha-carbon in the dehydroalanine unit that mimics the planar geometry of the anionic intermediate.  相似文献   

4.
Eight bradykinin potentiating peptides have been isolated in the pure form from the low-molecular-mass fraction of the venom of the Central Asian viper Echis multisquamatus Ch. The peptides isolated differed in the efficacy of their bradykinpotentiating activity and their capacity for inhibiting the angiotensin-converting enzyme (ACE, EC 3.4.15.1); however, complete correlation of the two activities was established for only six of them.Institute of Biochemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 62 32 56. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 435–440, May–June, 1995.  相似文献   

5.
A phospholipase A2 with a molecular mass of 12–14 kDa has been isolated from the venom of the spiderEresus niger by three-stage column chromatography. Asparagine has been identified as the N-terminal amino acid.  相似文献   

6.
A phospholipase A2 with a molecular mass of 12–14 kDa has been isolated from the venom of the spiderEresus niger by three-stage column chromatography. Asparagine has been identified as the N-terminal amino acid.Institute of Physiology, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 557–560, July–August, 1991.  相似文献   

7.
The physicochemical and functional properties of the venom, hemolymph, and egg extract of the karakurt spiderLatrodectus tredecimguttatuswere studied. A highly purified toxin that differs from the neurotoxins found previously in the venom was isolated from the hemolymph and characterized.  相似文献   

8.
A new calcium antagonist, CNS 2103, is isolated from the venom of a fishing spider, Dolomedes okefinokensis. The structure of this compound is derived from spectroscopic data, including tandem mass spectrometry. A flexible, convergent synthesis of CNS 2103 is described.  相似文献   

9.
胡朝暾  肖震  周熙  陈佳  陈波  刘中华 《色谱》2015,33(6):628-633
家福捕鸟蛛(Selenocosmia jiafu)是一种生活在中国广西、云南等边远山区、中等个体、产毒量较大和毒性较强的蜘蛛新种。为了对家福捕鸟蛛粗毒成分进行初步探索,采用反相高效液相色谱、基质辅助激光解吸离子化飞行时间质谱和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳方法对粗毒多肽和蛋白质的多样性进行了分析。结果表明:家福捕鸟蛛粗毒经色谱分离后得到40多个色谱峰,经质谱鉴定得到238个多肽,且多肽的相对分子质量呈现出双峰分布,其中62.5%的多肽的相对分子质量分布在3000~4500 之间,33.2%的多肽的相对分子质量分布在1000~3000之间。这种相对分子质量的分布模式不同于其他已经报道的蜘蛛粗毒中多肽的分布模式。电泳分析结果表明:除了相对分子质量在10000以下的多肽分子,粗毒在50、72和90 kD附近有3条明显的条带,粗毒电泳条带经液相色谱-电喷雾四极杆飞行时间质谱鉴定,主要是一些血蓝蛋白、钾离子通道蛋白、钙蛋白酶等。说明家福捕鸟蛛粗毒中多肽和蛋白质种类丰富。  相似文献   

10.
Antimicrobial peptides (AMPs), named lycocitin 1, 2 and 3, and a peptide with a monoisotopic molecular mass of 3038.70 Da were detected in the venom glands of the wolf spider Lycosa singoriensis. Two of the peptides, lycocitin 1 and 2, are new AMPs whereas lycocitin 3 is highly homologous to lycotoxin II isolated from the venom of spider Lycosa carolinensis. In addition, two other peptides with monoisotopic masses of 2034.20 and 2340.28 Da showing the motif typical for antimicrobial peptides were also identified. These peptides and lycocitin 1, 2 and 3 were de novo sequenced using electron capture dissociation and low-energy collisional tandem mass spectrometry. The amino acid sequence of lycocitin 1 was determined as GKLQAFLAKMKEIAAQTL-NH(2). Lycocitin 2 differs from lycocitin 1 by a replacement of a lysine residue for an arginine residue at the second position. Lycocitin 3 differs from the known lycotoxin II consisting of 27 amino acid residues by a deletion of Gly-26. Both lycocitin 1 and 2 inhibit growth of Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Escherichia coli) bacteria and fungi (Candida albicans, Pseudomonas aeruginosa) at micromolar concentrations.  相似文献   

11.
A novel polyamine toxin, named MG30, was isolated from the venom of the spider, Macrothele gigas, and its structure was elucidated by two-dimensional NMR and mass analysis. In addition, the enantioselective synthesis of MG30 was achieved to assign its absolute stereochemistry.  相似文献   

12.
The de novo sequence of a new peptide from venom of the East-European hornet Vespa orientalis L. was determined by mass spectrometry. It was used as an example to show that time-of-flight mass spectrometry with an electrospray ion source can be used effectively to determine the amino-acid sequence of microquantities of peptides. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 49–51, January–February, 2008.  相似文献   

13.
Using a new approach based on the NMR spectroscopic analysis of the entire, unpurified spider venom, we identified a family of unusual sulfated nucleoside derivatives from the venom of the hobo spider, Tegenaria agrestis. These compounds are ribonucleoside mono- and disulfates derived from guanosine and xanthosine, some of which are glycosylated, bearing one or two D-fucose units. The use of NMR spectroscopy to characterize the unfractionated venom was central to the discovery of this heretofore overlooked class of venom components.  相似文献   

14.
High-performance fibers from spider silk   总被引:3,自引:0,他引:3  
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15.
16.
From the toad venom Ch'an Su the cardenolides I, III and V have been isolated. It is the first time that cardenolides and bufadienolides are detected simultaneously in a biological material.  相似文献   

17.
Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Institute of Physiology and Biophysics, Academy of Sciences of the Republic of Uzbekistan, 700095, Tashkent, ul. Niyazova, 1. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 625–627, July–August, 1995. Original article submitted November 9, 1994.  相似文献   

18.
19.
Biogenic amines, which are components of tarantula Scodra griseipes venom, are studied using tandem mass spectrometry. Their heptafluoropropionic (PFP) derivatives are ionized under electron impact and isobutane-chemical ionization. Daughter- and parent-ion mass spectra under collisionally activated dissociation conditions provide a more detailed study of such derivatives. Discrimination of di(PFP)amines and tri and tetra(PFP)amines is possible because of the presence of diagnostic ions induced by collision.  相似文献   

20.
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