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《Bioscience, biotechnology, and biochemistry》2013,77(1):98-101
Two novel nematicidal cyclodepsipeptides, designated bursaphelocides A and B, were isolated from the culture filtrate of an imperfect fungus, strain D1084, belonging to Mycelia sterilia. Bursaphelocide A (1), containing 2-hydroxy-3-methylpentanoic acid, proline, isoleucine, N-methylalanine, N-methylvaline, and β-alanine in sequence, and bursaphelocide B (2), comprising 4-methylproline instead of proline in 1, are novel 2-hydroxy-3-methylpentanoic acid analogues of insecticidal destruxins. 相似文献
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Speransky AS Cimaglia F Krinitsina AA Poltronieri P Fasano P Bogacheva AM Valueva TA Halterman D Shevelev AB Santino A 《Biotechnology journal》2007,2(11):1417-1424
Five Kunitz protease inhibitor group B genes were isolated from the genome of the diploid non-tuber-forming potato species Solanum palustre. Three of five new genes share 99% identity to the published KPI-B genes from various cultivated potato accessions, while others exhibit 96% identity. Spls-KPI-B2 and Spls-KPI-B4 proteins contain unique substitutions of the most conserved residues usually involved to trypsin and chymotrypsin-specific binding sites of Kunitz-type protease inhibitor (KPI)-B, respectively. To test the inhibition of trypsin and chymotrypsin by Spls-KPI proteins, five of them were produced in E. coli purified using a Ni-sepharose resin and ion-exchange chromatography. All recombinant Spls-KPI-B inhibited trypsin; K(i) values ranged from 84.8 (Spls-KPI-B4), 345.5 (Spls-KPI-B1), and 1310.6 nM (Spls-KPI-B2) to 3883.5 (Spls-KPI-B5) and 8370 nM (Spls-KPI-B3). In addition, Spls-KPI-B1 and Spls-KPI-B4 inhibited chymotrypsin. These data suggest that regardless of substitutions of key active-center residues both Spls-KPI-B4 and Spls-KPI-B1 are functional trypsin-chymotrypsin inhibitors. 相似文献
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A novel trypsin inhibitor from Peltophorum dubium seeds,with lectin-like properties,triggers rat lymphoma cell apoptosis 总被引:1,自引:0,他引:1
Fernanda Troncoso M Cerdá Zolezzi P Hellman U Wolfenstein-Todel C 《Archives of biochemistry and biophysics》2003,411(1):93-104
A trypsin inhibitor (PDTI) was isolated from Peltophorum dubium seeds by affinity chromatography on a thyroglobulin-agarose or a trypsin-agarose column. In both cases, SDS-PAGE showed two bands of M(r) 20,000 and 22,000, which could not be resolved. Their amino-terminal sequences were identical and similar to that of Kunitz-type soybean trypsin inhibitor (SBTI). Mass spectrometry analysis of tryptic digests of both bands showed 16 coincident peaks, suggesting that they are closely related proteins. The K(i)s for trypsin and chymotrypsin inhibitory activity of PDTI were 1.6 x 10(-7) and 1.3 x 10(-5)M, respectively. Lectin-like activity of PDTI and SBTI, detected by hemagglutination of rabbit erythrocytes, was inhibited by sialic acid-containing compounds. PDTI and SBTI caused apoptosis of Nb2 rat lymphoma cells, demonstrated by decrease of viability, DNA hypodiploidy, DNA fragmentation, and caspase-3-like activity. They had no effect on normal mouse splenocytes or lymphocytes, whereas they caused apoptosis of concanavalin A-stimulated mouse lymphocytes. 相似文献
4.
Krauchenco S Pando SC Marangoni S Polikarpov I 《Biochemical and biophysical research communications》2003,312(4):1303-1308
The three-dimensional structure of a novel Kunitz (STI) family member, an inhibitor purified from Delonix regia seeds (DrTI), was solved by molecular replacement method and refined, respectively, to R(factor) and R(free) values of 21.5% and 25.3% at 1.75A resolution. The structure has a classical beta-trefoil fold, however, differently from canonical Kunitz type (STI) inhibitors, its reactive site loop has an insertion of one residue, Glu68, between the residues P1 and P2. Surprisingly, DrTI is an effective inhibitor of trypsin and human plasma kallikrein, but not of chymotrypsin and tissue kallikrein. Putative structural grounds of such specificity are discussed. 相似文献
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Revina TA Speranskaya AS Kladnitskaya GV Shevelev AB Valueva TA 《Biochemistry. Biokhimii?a》2004,69(10):1092-1098
A protein with molecular weight of 21 kD denoted as PKSI has been isolated from potato tubers (Solanum tuberosum L., cv. Istrinskii). The isolation procedure includes precipitation with (NH4)2SO4, gel chromatography on Sephadex G-75, and ion-exchange chromatography on CM-Sepharose CL-6B. The protein effectively inhibits the activity of subtilisin Carlsberg (Ki = 1.67 +/- 0.2 nM) by stoichiometric complexing with the enzyme at the molar ratio of 1 : 1. The inhibitor has no effect on trypsin, chymotrypsin, and the cysteine proteinase papain. The N-terminal sequence of the protein consists of 19 amino acid residues and is highly homologous to sequences of the known inhibitors from group C of the subfamily of potato Kunitz-type proteinase inhibitors (PKPIs-C). By cloning PCR products from the genomic DNA of potato, a gene denoted as PKPI-C2 was isolated and sequenced. The N-terminal sequence (residues from 15 to 33) of the protein encoded by the PKPI-C2 gene is identical to the N-terminal sequence (residues from 1 to 19) of the isolated protein PKSI. Thus, the inhibitor PKSI is very likely encoded by this gene. 相似文献
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During the seed development of Nicotiana tabacum, appreciable accumulation of the soluble protein fraction started to occur at around the 6th day after anthesis and finally reached 12% on the basis of dry weight when seed maturation was accomplished. In the soluble fraction of mature seeds, four protein fractions were observed on analytical ultracentrifugation, and the protein having a sedimentation coefficient of 11.7S was the major one. The 11.7S protein was isolated and SDS-polyacrylamide gel electrophoresis indicated that the protein consisted of at least five subunits with molecular weights of 49,000, 31,000, 29,000, 21,000 and 19,000. The 11.7S protein was rich in glutamic acid or glutamine and arginine, and the presence of carbohydrate was confirmed.During development, all of the five subunits started to appear during the period between the 12th and 15th day after anthesis. 相似文献
9.
Clemente Capasso Menico Rizzi Enea Menegatti Paolo Ascenzi Martino Bolognesi 《Journal of molecular recognition : JMR》1997,10(1):26-35
The crystal structure of bovine α-chymotrypsin (α-CHT) in complex with the bovine basic pancreatic trypsin inhibitor (BPTI) has been solved and refined at 2.8 Å resolution (R-factor=0.18). The proteinase:inhibitor complex forms a compact dimer (two α-CHT and two BPTI molecules), which may be stabilized by surface-bound sulphate ions, in the crystalline state. Each BPTI molecule, at opposite ends, is contacting both proteinase molecules in the dimer, through the reactive site loop and through residues next to the inhibitor's C-terminal region. Specific recognition between α-CHT and BPTI occurs at the (re)active site interface according to structural rules inferred from the analysis of homologous serine proteinase:inhibitor complexes. Lys15, the P1 residue of BPTI, however, does not occupy the α-CHT S1 specificity pocket, being hydrogen bonded to backbone atoms of the enzyme surface residues Gly216 and Ser217. © 1997 John Wiley & Sons, Ltd. 相似文献
10.
Minagawa S Sugiyama M Ishida M Nagashima Y Shiomi K 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2008,150(2):240-245
Sea anemones are rich in biologically active polypeptides such as toxins and protease inhibitors. These polypeptides have so far been isolated from whole bodies, tentacles or secreted mucus. Recently, two novel peptide toxins with crab lethality have been isolated from acrorhagi (specialized aggressive organs elaborated by only certain species of sea anemones belonging to the family Actiniidae) of Actinia equina. This prompted us to survey biologically active polypeptides in the acrorhagi of two species of sea anemones, Anthopleura aff. xanthogrammica and Anthopleura fuscoviridis. No potent crab lethality was displayed by the acrorhagial extracts of both species. However, significantly high protease inhibitory activity was instead detected in the acrorhagial extracts of the two species and also in that of A. equina. From the acrorhagi of A. equina, A. aff. xanthogrammica and A. fuscoviridis, one (AEAPI), one (AXAPI) and two (AFAPI-I and AFAPI-III) protease inhibitors were isolated, respectively. The complete amino acid sequences of the four inhibitors were elucidated by N-terminal sequencing and sequencing of the C-terminal peptide fragment produced upon asparaginylendopeptidase digestion. The determined amino acid sequences revealed that all the four inhibitors are new members of the Kunitz-type protease inhibitor family. 相似文献