摘要:

The complete amino acid sequence of rat SVS‐IV protein, consisting of 90 residues, has been determined. The sequence of rat SVS‐IV protein is the first seminal vesicle secretory protein determined and it does not show any homology with other known protein sequences. The secondary structure of SVS‐IV protein as analyzed by methods of Fasman and Chou indicates that this protein contains 53%α‐helix, 36%ß‐turn and 11%

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03047.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

A statistical molecular model for hydrated peptides is used to simulate the behaviour of various peptide chains in aqueous solution. The reliability of the model is ascertained by the evolution ofthe characteristic ratio, Cn, for hydrophobic and hydrophilic polypeptide chains, such as,respectively, poly‐Ala and poly‐Ser. The comparison of computed and experimental properties related to non radiative energy transfer of angiotensin II analogs, assuming that an ensemble of conformers is a satisfactory representation of the state of these molecules in water, provides further support for the mo

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03048.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

Three analogs of human β‐endorphin (βh‐EP) were synthesized by the solid‐phase method: βh‐EP‐(1–28) (II), [D‐Ala2, Gln8] ‐ βh‐EP‐(1–28) (III). Radioreceptor binding assay with use of tritiated βh‐EP as primary ligand gave relative potencies as follows: βh‐EP, 100; I, 85; II, 380; III, 146. Relative potencies in an analgesic assay were: βh

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03049.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

The Gly3residue in Gly2‐ and D‐Ala2‐enkephalins has been replaced by ΔAla3and Ser3in order to examine the effect on binding to the Δ and μ opiate receptors. [D‐Ala2, ΔAla3, Leu5]‐enkephalin maintains most of its receptor binding affinities for both sites. It is suggested that the proper conjunctions of positions 2 and 3 of the enkephalin sequence are important to receptor preference and that position 3 may have a very specific interaction with the Δ receptor. Thein vivoanalgesic and CNS activities of the peptides are

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03050.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

The preparation ofNα1N29‐bis‐methylsulphonylethyloxycarbonyl‐des‐alanineB30‐B‐chain‐disulphide‐OΛ13OΛ21‐dimethyl ester is described. Starting with the di‐S‐sulphonate‐B‐chain it was prepared by i) removal of the C‐terminal amino acid by digestion with carboxypeptidase A, ii) reduction and oxidation to form the cyclic disulphide, iii) esterification of the three carboxyl groups (αCOOH = LysB29, ΛCOOH = GluB13and GluB21) followed by selective tryptic hydrolysis of the α‐carboxyl ester, and iv) the protection of both amino groups (αNH2= PheB1, NH2= LysB29). This B‐chain derivative was activated selectively at the C‐terminal carboxyl group by formation of a mixed anhydride, and condensed with the dipeptide Thr‐Arg. All protecting groups were removed by treatment with alkali. The human‐B‐chain C‐terminal elongated with Arg was obtained in a yield of 30% base

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03051.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

A new algorithm has been developed for identifying helices, extended structures, and bends from the positions of the α‐carbon atoms using the virtual bond approach. The parameters used are two virtual bond angles (Δ1and Δ2), the virtual dihedral angle (θ), and the distance (D) between the terminal α‐carbon atoms of the tripeptide.The criteria for classification have been worked out by model building as well as from proteins whose complete secondary structures are known. These criteria are as follows: (i) |θ| ≤ 60° and (Δ1+Δ2) ≤ 230° for a bend, (ii) for a helix, successive θ's should not differ by more than 30°, and (iii) for an extended structure, the cumulative deviation of the above parameters should not vary by more than 20% from the ideal extended chain.The method developed has been applied successfully to three proteins wherein the coordinates of α‐carbon atoms alone are known and a complete mapping of the secondary structures has now been obtained. One interesting observation is that the percentage of residues not taking part in helices, extended structures, and bends is very smal

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03052.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

Lysozyme from pigeon egg white has been purified by ion exchange chromatography and gel filtration. The overall yield of the purification procedure is 65%. The specific activity of the enzyme is 15 000 units/mg. The influence of pH and ionic strength on the lytic activity of the protein, as well as its thermal stability, have been studied. The molecular weight, secondary structure estimation, amino acid composition, NH2‐ and COOH‐terminal sequence of the protein are also reported. The pigeon enzyme has been classified as a chicken type lysozyme (lysozyme c) according to the obtained resu

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03053.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

Cyl‐2 is a phytotoxic cyclic tetrapeptide with the sequence ofcyclo(‐D‐Tyr(Me)‐L‐Ile‐L‐Pip‐Aoe‐): Aoe, 2‐amino‐8‐oxo‐9,10‐epoxydecanoic acid. The configuration of Aoe is unknown. Three analogs,cyclo(‐D‐Tyr(Me)‐L‐Ile‐L‐Pip‐L(and D)‐Leu‐) (1 and 2) andcyclo(‐D‐Tyr(Me)‐L‐Ile‐L‐Pro‐D‐Leu‐) (3), were synthesized and spectroscopic features of these analogs were compared.1H‐N.m.r. spectra ofcyclo(‐D‐Tyr(Me)‐L‐Ile‐L‐Pip‐L‐Leu‐) (1), cyclo(‐D‐Tyr(Me)‐L‐Ile‐L‐Pro‐L‐Leu‐) (4), and Cyl‐2 showed a similar pattern. On the other hand, the

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03054.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

By working at very low protein concentration (ca. 0.003%), it is possible to measure tryptophyl fluorescence intensity at 350nm (F350) of bovine plasma albumin (BPA) as a function of pH under precipitating conditions (acidic concentrated salt solutions). Under such conditions, distinct changes in F350were seen before the starting of precipitation of BPA and no further changes in F350over the precipitating pH range. Comparison of pH‐profiles monitored by F350with those by solubility in the presence of various salts at various concentrations indicated that the change of solubility is observed after definite changes in conformation of the protei

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03055.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

Dipeptides of threo‐ and erythro‐β‐hydroxyaspartic acid were transformed intoO‐tosyl derivatives, which on base‐catalyzed elimination gave aminofumaric acid derivatives. The possible mechanism ofthis process and the spectroscopic properties of the elimination products are

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1982.tb03056.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY