摘要:

The conformational energy for the pentapeptide Arg‐Lys‐Asp‐Val‐Tyr (TP5) is calculated using empirical potential functions. Calculation of the local interactions for each independent residue gives a local energy term for which the probabilities as a function of ø, ø are plotted on Ramachandran‐type maps. The interaction energy between residues is calculated only for these points in the maps with maximum probability. The most probable conformation for TP5 is found to have an extended backbone arrangement having the Arg and Tyr side‐chains folded over the backbone.13C n.m.r. spin lattice relaxation time measurements show no increase in T1of the α‐carbons at the first and terminal amino acids. The increase in T1along the sidechain as found for Lys does not occur for Arg and Tyr. These signs of reduced mobility are consistent with a set of folded conformations in which the Arg and Tyr sidechains have hindered internal rotations. The vicinal NH‐CαH couplings agree well with those calculated for the most probable conformer. This is not so for the CαH‐CβH couplings. These data are consistent with previous n.m.r. and str

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1984.tb02696.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The effect of low pH on the molecular properties of mustard 12S protein has been studied by the techniques of ultracentrifugation, viscometry, electrophoresis, turbidimetry, u.v. difference spectroscopy, fluorescence spectroscopy and circular dichroism. Ultracentrifugation and electrophoresis experiments indicated dissociation of the protein in the pH range 5.0 to 3.0 and below this pH reaggregation was indicated. Viscosity, turbidimetry, u.v. difference spectroscopy, fluorescence spectroscopy and circular dichroism studies showed that denaturation of the protein occurred between pH 5.0 and 3.0 and refolding at pH values below 3.0.

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1984.tb02697.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The structure of the title compound displays a buckled diketopiperazine ring. The two side‐chains are both folded, with the imidazole ring facing the methionine chain. Imidazole nitrogen is the primary site for metal coordination of the ligand. Only for copper (II) adducts and in the solid state are there evidences of additional coordination through the sulfur ato

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1984.tb02698.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1984.tb02699.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1984.tb02700.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY