摘要:

The conformational properties of (Pro‐Leu‐Gly)10, (Pro‐Leu‐Gly)nand (Leu‐Pro‐Gly)nwere investigated both in solution and in solid state. By circular dichroism studies it was possible to demonstrate the formation of an ordered collagen‐like structure for (Pro‐Leu‐Gly)nin hexafluoroisopropanol–water mixtures and in ethylene glycol; (Leu‐Pro‐Gly)nassumes an ordered conformation only in ethylene glycol; (Pro‐Leu‐Gly)10is unordered under all the conditions studied.X‐ray diffraction patterns indicated that (Pro‐Leu‐Gly)nand (Leu‐Pro‐Gly)nassume a triple helical structure in solid state. In addition, the investigation of (Pro‐Leu‐Gly)nstrongly suggests that this type of structure is a single chain triple helix. The X‐ray patterns of (Pro‐Leu‐Gly)10do not allow us to ascertain a collagen or polypr

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02463.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The1H‐ and13C‐n.m.r. spectra of eledoisin and minor oligopeptides were measured and assigned. The proton spectra were interpreted on the basis of homonuclear decoupling, chemical shift criteria and spectra simulation. The information obtained was used in the assignment of the13C spectrumviaheteronuclear decoupling1H‐13C. The steric arrangement of proline residue was deduced from the13C spectrum. Moreover the similarity of the13C spectrum of eledoisin with that of component oligopeptides suggests that no considerable conformational change occurs in the undecapeptide relative to the component frag

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02464.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

A lattice model of proteins is introduced. “A protein molecule” is a chain of non‐intersecting units of a given length on the two‐dimensional square lattice. The copolymeric character of protein molecules is incorporated into the model in the form of specificities of inter‐unit interactions. This model proved most effective for studying the statistical mechanical characteristics of protein folding, unfolding and fluctuations. The specificities of inter‐unit interactions are shown to be the primary factors responsible for the all‐or‐none type transition from native to denatured states of globular proteins. The model has been studied by the Monte Carlo method of Metropolis et al., which is now shown applied to approximately simulating a kinetic process. In the strong limit of the specificity of the inter‐unit interaction the native conformation was reached in this method by starting from an extended conformation. The possible generalization and application of this method for finding the native conformation of proteins from their amino acid seque

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02465.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Hydrolysis rates of N‐acetyl dehydroalanine methyl ester (methyl 2‐acetamidoacrylate) and related model compounds were measured in aqueous, organic and mixed aqueous media. Adding dimethyl sulfoxide (DMSO) to water, retarded hydrolysis of the ester by a factor of 2 to 500, depending on the pH of the medium and concentration of DMSO. Ethanol also slowed hydrolysis, but the effect was not so pronounced. Related studies show that the acetamido group C‐N bond of sodium 2‐acetamido‐acrylate is hydrolyzed only about 1/130 as fast as the ester group C‐O bond. Aqueous dimethyl sulfoxide should be a useful medium for synthesis of peptide, amino acid and protein derivatives of N‐acetyl dehydroalanine

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02466.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Conditions leading to the cleavage of both disulfide bridges in human growth hormone caused the reduction of only one disulfide bond in bovine growth hormone. Partially reduced and alkylated derivatives of bovine growth hormone were prepared and characterized. It was shown that the reduction and alkylation modified the COOH‐terminal disulfide bond, however, this modification does not result in the dissociation of the dimeric form of bovine growth hormone or cause a significant loss of growth‐promoting activ

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02467.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The sequential copolymer (Pro‐Pro‐β‐Ala)nhas been synthesized as a model for collagen. Preliminary studies indicate that the polymer may bear conformational resemblance to co

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02468.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Ethly vinyl sulfone (EVS) alkylates ε‐amino groups of lysine side chains and imidazole groups of histidine residues in proteins. Amino acid analysis of hydrolyzates of EVS‐treated polylysine shows that lysine forms two derivatives, presumably ε‐N‐(ethylsulfonylethyl)lysine and ε, N, N‐bis(ethylsulfonylethyl)lysine that are eluted as well‐resolved peaks on the (long basic) physiological column of our amino acid analyzer at about 118 and 60 min, respectively. Peaks with identical elution times were also observed after EVS‐treatment of BSA and wool. The postulated histidine derivative, presumably N3‐im‐(ethylsulfonylethyl)histidine is also eluted as a well‐resolved peak on the same column at about 90 min. A peak with an identical elution time was observed in a hydrolyzate of EVS‐treated polyhistidine. The described alkylation has potential utilit

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02469.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The disulfide linkage of the 12 half‐cystine residues in the β subunit of ovine interstitial cell stimulating hormone has been investigated by enzymic and partial acid hydrolysis of the intact molecule. Results indicate that the disulfide bridges are formed by residues 9–38, 23–72, 26–110, 34–90, 57–88

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02470.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The peptide [165, 182, 189‐S‐carbamidomethylcysteine]‐human growth hormone‐(140–191) has been synthesized by the solid‐phase method. The complement fixation, lactogenic and growth‐promoting activities of the synthetic peptide were comparable to that of [165, 182, 189‐S‐carbamidomethylcysteine]‐human growth hormone‐(141–191) that was derived

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02471.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

ISSN:0367-8377    

DOI:10.1111/j.1399-3011.1975.tb02472.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY