International journal of peptide and protein research最新文献_第9页

Synthesis and properties of chemotactic peptide analogs. II. HCO-Met-Leu-Phe-OMe analogs containing cyclic alpha,alpha-disubstituted amino acids as Met and Phe mimicking residues. 趋化肽类似物的合成及性质。2含有环α， α -二取代氨基酸作为Met和Phe模拟残基的HCO-Met-Leu-Phe-OMe类似物。

International journal of peptide and protein research Pub Date : 1991-12-01

I Torrini, G Pagani Zecchini, M Paglialunga Paradisi, G Lucente, E Gavuzzo, F Mazza, G Pochetti, S Spisani, A L Giuliani

{"title":"Synthesis and properties of chemotactic peptide analogs. II. HCO-Met-Leu-Phe-OMe analogs containing cyclic alpha,alpha-disubstituted amino acids as Met and Phe mimicking residues.","authors":"I Torrini, G Pagani Zecchini, M Paglialunga Paradisi, G Lucente, E Gavuzzo, F Mazza, G Pochetti, S Spisani, A L Giuliani","doi":"","DOIUrl":"","url":null,"abstract":"As a part of a research program aimed at studying structure activity relationship in the field of chemotactic peptides, modified analogs of the potent chemoattractant HCO-Met-Leu-Phe-OH (fMLP) of the general formula HCO-Xaa-Leu-Yaa-OMe are examined. 4-Aminotetrahydrothiopyran-4-carboxylic acid (Thp) and 2-aminoindane-2-carboxylic acid (Ain) have been chosen as achiral, conformationally restricted amino acids suitable to mimick the external Met and Phe residues of fMLP-OMe. Studies on a first model, namely [Ain3]fMLP-OMe 1, have already been reported (12). Here the two remaining analogs [Thp1, Ain3] 2 and [Thp1] 3 have been synthesized. The conformation in the crystal of the disubstituted analog 2 has been determined and compared with those adopted by the parent fMLP-OMe and by previously studied models. The backbone conformation of 2 is characterized by helical folding centred at each of the three residues with the central Leu presenting helical handedness opposite to those of the two adjacent achiral residues. This conformation presents strong similarities with that adopted in the crystal by fMLP-OMe and resembles the conformation of fMLP bound to immunoglobulin (Bence-Jones dimer). The conformationally restricted analogs 2 and 3 are more active than the parent in the stimulation of directed mobility of human neutrophils but are practically inactive in the superoxide production. Crystals of 2 are orthorhombic, s.g. P2(1)2(1)2(1), with a = 21.934 (8), b = 10.856 (2), c = 10.380 (2) A. The structure has been refined to R = 0.071 for 2301 independent reflections with I greater than 1.5 sigma.","PeriodicalId":14204,"journal":{"name":"International journal of peptide and protein research","volume":"38 6","pages":"495-504"},"PeriodicalIF":0.0,"publicationDate":"1991-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12833884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A CD strategy for the study of polypeptide folding/unfolding. A synthetic foot-and-mouth disease virus immunogenic peptide. 用于多肽折叠/展开研究的CD策略。一种合成的口蹄疫病毒免疫原肽。

International journal of peptide and protein research Pub Date : 1991-12-01

G Siligardi, A F Drake, P Mascagni, D J Rowlands, F Brown, W A Gibbons

{"title":"A CD strategy for the study of polypeptide folding/unfolding. A synthetic foot-and-mouth disease virus immunogenic peptide.","authors":"G Siligardi, A F Drake, P Mascagni, D J Rowlands, F Brown, W A Gibbons","doi":"","DOIUrl":"","url":null,"abstract":"The circular dichroism spectrum of the 20-residue immunogenic peptide from the foot-and-mouth disease virus (VP1; 141-160 of serotype A, subtype 12) was solvent- and temperature-dependent. Careful solvent titration revealed two isodichroic points and plateaux consistent with stepwise unfolding of specific stable conformations. Variable temperature studies in cryogenic solvents and urea perturbation were consistent with the existence of three conformational moieties, the left-handed extended helix, the alpha-helix, and the 3(10) helix. The number of residues in each helix was confirmed by CD spectral simulations. The strategy described here can be used to determine the components of a conformational equilibrium and their statistical weights, to study peptide folding and unfolding and to determine the bioactive conformation(s) of linear peptides. The conclusions were supported by 2D-NMR studies. A new mechanism for the stabilization of left-handed extended helices and destabilization of alpha-helices by urea is proposed. The structure of the peptide as resolved by CD spectroscopy is of particular significance since the conformation of this antigenic sequence in situ has so far not been solved by X-ray crystallography.","PeriodicalId":14204,"journal":{"name":"International journal of peptide and protein research","volume":"38 6","pages":"519-27"},"PeriodicalIF":0.0,"publicationDate":"1991-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12890587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evidence for a beta-turn in an azadipeptide sequence. Synthesis and crystal structure of ButCO-Pro-AzaAla-NHPri. 偶氮二肽序列发生β转变的证据。ButCO-Pro-AzaAla-NHPri的合成及晶体结构。

International journal of peptide and protein research Pub Date : 1991-12-01

Z Benatalah, A Aubry, G Boussard, M Marraud

引用次数: 0

Conformational analysis of peptide surrogates. Reduced and retro-amide links in blocked alanine and in secondary structures. 肽替代物的构象分析。阻断丙氨酸和二级结构中的减少和反酰胺连接。

International journal of peptide and protein research Pub Date : 1991-10-01

P Dauber-Osguthorpe, M M Campbell, D J Osguthorpe

引用次数: 0

Ten-membered cyclotripeptides. III. Synthesis and conformation of cyclo(-Me beta Ala-Phe-Pro-) and cyclo(-Me beta Ala-Phe-DPro-). 拥有cyclotripeptides。3环(- me β ala - ph - pro -)和环(- me β ala - ph - dpro -)的合成和构象。

International journal of peptide and protein research Pub Date : 1991-10-01

S Cerrini, E Gavuzzo, G Lucente, G Luisi, F Pinnen, L Radics

{"title":"Ten-membered cyclotripeptides. III. Synthesis and conformation of cyclo(-Me beta Ala-Phe-Pro-) and cyclo(-Me beta Ala-Phe-DPro-).","authors":"S Cerrini, E Gavuzzo, G Lucente, G Luisi, F Pinnen, L Radics","doi":"","DOIUrl":"","url":null,"abstract":"The 10-membered cyclotripeptide cyclo(-Me beta Ala-Phe-Pro) 3 and its diastereoisomer cyclo(-Me beta Ala-Phe-DPro-) 4 have been synthesized under mild cyclization conditions starting from linear precursors containing C-terminal proline. The crystal and molecular structure of the two models has been determined by X-ray crystallography. Analysis of the NMR spectra supported by NOE data clearly indicates that the conformations found in the crystals are retained in solution. Both cyclotripeptides exhibit a cis-cis-trans backbone conformation. The two tertiary peptide bonds, at the proline and Me beta Ala nitrogen atoms, adopt a cis conformation whereas the CO-NH junctions are trans in both the models. The deviations from planarity of the peptide units vary from delta omega values of ca. 18 degrees for the Pro-Me beta Ala and DPro-Me beta Ala bonds to ca. 7 degrees for Phe-Pro and Phe-DPro bonds. Relevant conformational details of 3 and 4, as revealed by X-ray and NMR analysis, are reported. Crystals of 3 are monoclinic: P2(1), a = 5.317(2), b = 17.059(6), c = 9.514(3) A, beta = 99.18(3), Z = 2. The final R and Rw are 0.054 and 0.071 respectively. Crystals of 4 are orthorhombic: P2(1)2(1)2(1), a = 8.797(2), b = 19.440(9), c = 21.605(10) A, Z = 8. The final R and Rw are 0.069 and 0.104 respectively.","PeriodicalId":14204,"journal":{"name":"International journal of peptide and protein research","volume":"38 4","pages":"289-97"},"PeriodicalIF":0.0,"publicationDate":"1991-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12959177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stereocontrolled synthesis of psi[CH = CH] dipeptide isosteres. 立体控制合成psi[CH = CH]二肽同工异构体。

International journal of peptide and protein research Pub Date : 1991-09-01

D J Kempf, X C Wang, S G Spanton

引用次数: 0

Dimensional oscillation. A fast variation of energy embedding gives good results with the AMBER potential energy function. 维振荡。能量嵌入的快速变化使琥珀势能函数具有较好的效果。

International journal of peptide and protein research Pub Date : 1991-08-01

M E Snow, G M Crippen

引用次数: 0

Chemical synthesis of human beta-endorphin(1-27) analogs by peptide segment coupling. Leucine and glycine residues bearing thiocarboxyl functions as junctions for peptide segment coupling. 肽段偶联法合成人β -内啡肽(1-27)类似物。含有硫羧基的亮氨酸和甘氨酸残基作为肽段偶联的连接。

International journal of peptide and protein research Pub Date : 1991-07-01

H C Cheng, D Yamashiro

{"title":"Chemical synthesis of human beta-endorphin(1-27) analogs by peptide segment coupling. Leucine and glycine residues bearing thiocarboxyl functions as junctions for peptide segment coupling.","authors":"H C Cheng, D Yamashiro","doi":"","DOIUrl":"","url":null,"abstract":"[Gly8]beta hEP(1-27)NH2 and [L-Leu8]beta hEP(1-27)NH2, two analogs of human beta-endorphin, were synthesized by both all-stepwise solid phase synthesis and peptide segment coupling. For the peptide segment coupling method, two thiocarboxyl peptides. Msc-[Gly8]beta hEP(1-8)SH and Msc-[L-Leu8]beta hEP(1-8)SH, were synthesized by standard solid phase method on 4-[alpha-(Boc-Gly-S)benzyl]phenoxyacetamidomethy-resin and 4-[alpha-(Boc-L-Leu-S)benzyl]phenoxyacetamidomethy-resin. These two thiocarboxyl peptides were coupled to H-[Lys(Cit)9,19,24]-beta hEP(9-27)NH2. [Gly8]beta hEP(1-27)NH2 and [L-Leu8]beta hEP(1-27)NH2 were obtained after removal of Msc groups and citraconyl groups from products of the segment coupling reaction. The yields of both [Gly8]beta hEP(1-27)NH2 and [L-Leu8]beta hEP(1-27)NH2 in the segment coupling reaction were approximately 18%. Less than 1% of racemization of Leu-8 occurred during coupling of Msc-[L-Leu8]beta hEP(1-8)SH to H-[Lys(Cit)9,19,24]-beta hEP(9-27)NH2. Results of amino acid composition analysis, analysis by reverse phase high pressure liquid chromatography and receptor binding activity assays of the analogs showed that peptide analogs prepared by segment coupling method and those prepared by all-stepwise solid phase synthesis were identical. Results of receptor binding activity assays suggested that the molecular charge properties of beta-endorphin(1-27) and its analogs influenced the receptor binding activity.","PeriodicalId":14204,"journal":{"name":"International journal of peptide and protein research","volume":"38 1","pages":"70-8"},"PeriodicalIF":0.0,"publicationDate":"1991-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12823395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Chemical modification of human growth hormone with N-acetylimidazole. Effect on binding capacity to lactogenic and somatogenic receptors. n -乙酰咪唑对人生长激素的化学修饰。对产乳和产体受体结合能力的影响。

International journal of peptide and protein research Pub Date : 1991-07-01

P Kaliman, M R Ermácora, C Nowicki, C Wolfenstein-Todel, J A Santomé

引用次数: 0

Peptides from chiral C alpha,alpha-disubstituted glycines. Crystallographic characterization of conformation of C alpha-methyl, C alpha-isopropylglycine [(alpha Me)Val] in simple derivatives and model peptides. 手性C -二取代甘氨酸生成的肽。C -甲基，C -异丙基甘氨酸[(α Me)Val]在简单衍生物和模型肽中的构象的晶体学表征。

International journal of peptide and protein research Pub Date : 1991-06-01

G Valle, M Crisma, C Toniolo, S Polinelli, W H Boesten, H E Schoemaker, E M Meijer, J Kamphuis

{"title":"Peptides from chiral C alpha,alpha-disubstituted glycines. Crystallographic characterization of conformation of C alpha-methyl, C alpha-isopropylglycine [(alpha Me)Val] in simple derivatives and model peptides.","authors":"G Valle, M Crisma, C Toniolo, S Polinelli, W H Boesten, H E Schoemaker, E M Meijer, J Kamphuis","doi":"","DOIUrl":"","url":null,"abstract":"The molecular and crystal structures of one derivative and three model peptides (to the pentapeptide level) of the chiral C alpha,alpha-disubstituted glycine C alpha-methyl, C alpha-isopropylglycine [(alpha Me)Val] have been determined by X-ray diffraction. The derivative is mClAc-L-(alpha Me)Val-OH, and the peptides are Z-L-(alpha Me)Val-(L-Ala)2-OMe monohydrate, Z-Aib-L-(alpha Me)Val-(Aib)2-OtBu, and Ac-(Aib)2-L-(alpha Me)Val-(Aib)2OtBu acetonitrile solvate. The tripeptide adopts a type-I beta-turn conformation stabilized by a 1----4N--H...O = C intramolecular H-bond. The tetra- and pentapeptides are folded in regular right-handed 3(10)-helices. All four L-(alpha Me)Val residues prefer phi, psi angles in the right-handed helical region of the conformational map. The results indicate that: (i) the (alpha Me)Val residue is a strong type-I/III beta-turn and helix former, and (ii) the relationship between (alpha Me)Val chirality and helix screw sense is the same as that of C alpha-monosubstituted protein amino-acids. The implications for the use of the (alpha Me)Val residue in designing conformationally constrained analogues of bioactive peptides are briefly discussed.","PeriodicalId":14204,"journal":{"name":"International journal of peptide and protein research","volume":"37 6","pages":"521-7"},"PeriodicalIF":0.0,"publicationDate":"1991-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13077171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0