Biochimica et Biophysica Acta (BBA) - Protein Structure最新文献

{"title":"Purification and characterization of four components of rat caseins","authors":"Masaaki Hirose ,&nbsp;Toshio Kato ,&nbsp;Kenji Omori ,&nbsp;Makoto Takeuchi ,&nbsp;Masaaki Yoshikawa ,&nbsp;Ryuzo Sasaki ,&nbsp;Hideo Chiba","doi":"10.1016/0005-2795(81)90127-6","DOIUrl":"10.1016/0005-2795(81)90127-6","url":null,"abstract":"<div><p>Rat casein components (C1-, C3A-, C3B- and C4-casein) were extensively purified from rat milk, and the properties of these proteins were compared with those of other caseins including rat C2-casein. C1-casein was precipitated by a low concentration of CaCl₂ (1.5 mM). Both C3A- and C3B-casein were less sensitive to Ca²⁺ than were C1- and C2-casein, and the presence of 20 mM CaCl₂ was required at 37°C for their precipitation. C4-casein was absolutely insensitive to Ca²⁺. This protein exhibited the ability to stabilize all of the other rat casein components against Ca²⁺-dependent precipitation. In addition, C4-casein contained sialic acid, galactose and <span><math><mtext>N-</mtext><mtext>acetylgalactosamine</mtext></math></span>. Therefore, C4-casein appears to be a bovine ϰ-casein-like protein.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 139-145"},"PeriodicalIF":0.0,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90127-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18336937","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}

{"title":"A new pentraxin (serum amyloid P-component) in the rat: Evidence for two quaternary structures and effect of ligands on self-association","authors":"M. Pontet ,&nbsp;M. D'Asnieres ,&nbsp;D. Gache ,&nbsp;J. Escaig ,&nbsp;R. Engler","doi":"10.1016/0005-2795(81)90135-5","DOIUrl":"10.1016/0005-2795(81)90135-5","url":null,"abstract":"<div><p>A new rat serum protein has been isolated by affinity chromatography using ethanolamine- or phosphoethanolamine-substituted agarose gels. This protein has the morphological and functional characteristics of serum amyloid P-component and C-reactive protein. It comprises C₅ cyclic symmetry structure with non covalently cross-linked subunits which have calcium-dependent binding sites. We have called this protein rat serum amyloid P-component since it has all the properties typical of human serum amyloid P-component: it is made up of 10 subunits, it contains sialic acid and hexoses, it forms macroscopic polymers and it does not precipitate with pneumococcal C-polysaccharide. Rat amyloid P-component has three remarkable properties. Electron microscopy has shown that apart from pentagonal figures and stacked discs, rat P-component has a C₁₀ cyclic symmetry structure. Rat amyloid P-component has an affinity for specific ligands, such as phosphorylcholine or phosphoethanolamine. These ligands are able to depolymerize self-associated rat P-component. With these characteristics, rat serum amyloid P-component could prove to be an important model in the study of the relations between amyloid P-component and amyloidosis.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 202-210"},"PeriodicalIF":0.0,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90135-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18336940","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}

{"title":"Acrylamide quenching studies with azurin B","authors":"Roger Mallinson,&nbsp;Roseann Carter,&nbsp;Camillo A. Ghiron","doi":"10.1016/0005-2795(81)90124-0","DOIUrl":"10.1016/0005-2795(81)90124-0","url":null,"abstract":"<div><p>The acrylamide quenching of holoazurin B was studied as a function of emission wavelength in order to investigate discrepancies in interpretation of previous fluorescence measurements. A red-fluorescing acrylamide-quenchable component, which may be an impurity, is observed, suggesting that prior studies need to be interpreted with great caution. The presence of this component is not detectable when the 3-fold more fluorescent apo form is studied. Significant acrylamide quenching of apoazurin B is observed. The quenching constant of 5 · 10⁷ M⁻¹ · s⁻¹ at 20°C and the activation energy of 17 kcal/mol obtained are the most extreme values yet reported for a single tryptophan-containing protein. Since azurin B's indole is definitively known to be buried in the hydrophobic interior of the molecule, these results provide additional support for the contention that light-excited proteins undergo structural fluctuations in the nanosecond time range.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 117-122"},"PeriodicalIF":0.0,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90124-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73004603","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}

{"title":"Analysis of the near-ultraviolet circular dichroic spectra of staphylococcal enterotoxins A, B and C","authors":"Leonard Spero","doi":"10.1016/0005-2795(81)90134-3","DOIUrl":"10.1016/0005-2795(81)90134-3","url":null,"abstract":"<div><p>The near-ultraviolet CD spectra from 260 to 300 nm of staphylococcal enterotoxins A, B and C were resolved empirically into Gaussian curves. Each spectrum contained the same six components with maximum ellipticities at virtually identical wavelengths. The rotatory strength of the bands of enterotoxin A, however, differed significantly from that of enterotoxins B and C. Each Gaussian curve was identified as corresponding to a prominent CD transition of an aromatic chromophore: two phenylalanine bands from its ¹L_b transition (<span><math><mtext>0-0 </mtext><mtext>and</mtext><mtext> 0 + 930 </mtext><mtext>cm</mtext><msup><mi></mi><mn>−1</mn></msup></math></span>); four tyrosine bands from its ¹L_b transition (the 800 cm⁻¹ primary vibronic progression) with the weakest of these overlapping a phenylalanine band; and one ¹L_b tryptophan band. At alkaline pH, tyrosylate CD bands arose, centered at 247–249 nm and at 295–298 nm. The low intensity of the 295–298-nm bands indicated that most of the tyrosine CD in the neutral enterotoxins was contributed by buried residues. The tryptophan contribution to the CD of enterotoxin A was positive, while that of B and C was negative. Also indicative of a different milieu was the ready oxidation of the A toxin by <span><math><mtext>N-</mtext><mtext>bromosuccinimide</mtext></math></span> and the unavailability of the single tryptophan residue in the other two toxins to this reagent. The environment of the disulfide bond was markedly diverse in the three enterotoxins. Enterotoxin C was refractory to reduction by mercaptoethanol under conditions where enterotoxins B and A were readily reduced. The contribution of the disulfide of enterotoxin B to its CD spectrum was positive with an intensity of about 9000 deg · cm² · dmol⁻¹ and was centered near 273 nm. The difference spectrum between native and reduced enterotoxin A was much smaller and appeared to be conformational in origin.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 193-201"},"PeriodicalIF":0.0,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90134-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18336939","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}

{"title":"Protamine interacts with the D-domains of fibrinogen","authors":"Kazunori Okano,&nbsp;Yuji Saito,&nbsp;Ayako Matsushima,&nbsp;Yuji Inada","doi":"10.1016/0005-2795(81)90130-6","DOIUrl":"10.1016/0005-2795(81)90130-6","url":null,"abstract":"<div><p>The mechanism of precipitation of fibrinogen in the presence of a basic protein, protamine, has been investigated. The precipitation was clearly inhibited by the addition of Fragment D. Photooxidation of fibrinogen abolished the association caused by thrombin, but it did not affect the precipitation brought about by protamine. Not only fibrinogen but also fibrin monomer precipitated in the presence of protamine. These results led to the conclusion that protamine bound directly with D-domains of fibrinogen (of fibrin monomer) to cause the precipitation.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 164-167"},"PeriodicalIF":0.0,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90130-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17238147","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}

{"title":"Studies on the primary structures of the exocellular d-alanyl-d-alanine peptidases of Streptomyces strain R61 and Actinomadura strain R39","authors":"Colette Duez ,&nbsp;Jean-Marie Frère ,&nbsp;Jean-Marie Ghuysen ,&nbsp;Jozef Van Beeumen ,&nbsp;Joël Vandekerckhove","doi":"10.1016/0005-2795(81)90123-9","DOIUrl":"10.1016/0005-2795(81)90123-9","url":null,"abstract":"<div><p>The <span><math><mtext>M</mtext><msub><mi></mi><mn><mtext>r</mtext></mn></msub></math></span> 37 000 <span>d</span>-alanyl-<span>d</span>-alanine peptidase excreted by <em>Streptomyces</em> R61 and the <span><math><mtext>M</mtext><msub><mi></mi><mn><mtext>r</mtext></mn></msub></math></span> 530 00 <span>d</span>-alanyl-<span>d</span>-alanine peptidase excreted by <em>Actinomadura</em> R39 are both characterized by a very uneven distribution of the basic (<span><math><mtext>Arg + Lys</mtext></math></span>) amino acid residues. Trypsin degradation of the heat-denatured enzymes generates (1) thirteen soluble peptides which contain from 2 to 28 residues in the case of the R61 enzyme and nineteen soluble peptides which contain 2 to 39 residues in the case of the R39 enzyme; and (2) three large segments or core peptides which, irrespective of the enzymes from which they originate, consist of 50–60, 70–80 and 110–120 residues. About 90% of the basic (<span><math><mtext>Arg + Lys</mtext></math></span>) amino acid residues are recovered in the soluble tryptic peptides. The core peptides represent 62% (<span><math><mtext>M</mtext><msub><mi></mi><mn><mtext>r</mtext></mn></msub><mtext> ≈ 23 000</mtext></math></span>) and 45% (<span><math><mtext>M</mtext><msub><mi></mi><mn><mtext>r</mtext></mn></msub><mtext> ≈ 24 000</mtext></math></span>) of the untreated R61 and R39 enzymes, respectively. One 28-residue soluble peptide isolated from the R61 enzyme represents the N-terminal portion of the protein whose sequence has been established. The penicillin attachment site of the R61 enzyme has been located in one of the core peptides. For the R39 enzyme, indirect evidence shows that the penicillin binding site is probably within one of the soluble peptides.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 109-116"},"PeriodicalIF":0.0,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90123-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18082013","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}

{"title":"Porcine pancreatic lipase. Completion of the primary structure","authors":"J. De Caro,&nbsp;M. Boudouard,&nbsp;J. Bonicel,&nbsp;A. Guidoni,&nbsp;P. Desnuelle,&nbsp;M. Rovery","doi":"10.1016/0005-2795(81)90126-4","DOIUrl":"10.1016/0005-2795(81)90126-4","url":null,"abstract":"<div><p>The complete primary structure of a lipase (triacylglycerol hydrolase; EC 3.1.1.3) is presented for the first time. The porcine pancreatic enzyme which was investigated is composed of a single chain of 449 amino acids. Upon fragmentation by CNBr, five peptides were obtained. The sequence of four of them (CN I-CN IV) has already been published. The present report deals with the arrangement of the 142 amino acids of the C-terminal peptide CN V, thus completing the analysis of the whole molecule. Special problems resulting from incomplete cleavage of some peptide bonds in CN V and aggregation of large peptides were overcome using Sephadex filtration of succinylated derivatives in 50% acetic acid, antomated sequence analysis of peptide mixtures and subdigestion of material which could not be directly resolved. No obvious homology was found when the sequence of porcine lipase was compared with other protein, including pancreatic phospholipase A2 and colipase from the same species. However, a few similarities which might be significant were detected between the environment and relative position of certain half cystines in lipase and colipase, as well as between two tyrosine-rich regions existing in both proteins.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 129-138"},"PeriodicalIF":0.0,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90126-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18336936","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}

{"title":"A tentative elucidation of the sequence of human triosephosphate isomerase by homology peptide mapping","authors":"Pau M. Yuan,&nbsp;John M. Talent,&nbsp;Robert W. Gracy","doi":"10.1016/0005-2795(81)90136-7","DOIUrl":"10.1016/0005-2795(81)90136-7","url":null,"abstract":"<div><p>By utilizing homologous peptide mapping and amino acid analysis of recovered peptides, it has been possible to infer much of the sequence of human triosephosphate isomerase. This has been achieved with less than 5 mg of the human enzyme. The enzyme shows a great sequence homology with the rabbit enzyme. The methods used in this study can provide a rapid procedure for gaining structural information on human enzymes available only in microgram or milligram quantities.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 211-218"},"PeriodicalIF":0.0,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90136-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18336941","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}

{"title":"Low-frequency vibrations of ferroprotoporphyrin-substituted imidazole complexes. A resonance Raman study","authors":"Alain Desbois ,&nbsp;Marc Lutz","doi":"10.1016/0005-2795(81)90131-8","DOIUrl":"10.1016/0005-2795(81)90131-8","url":null,"abstract":"<div><p>This article reports the low-frequency regions of resonance Raman spectra of five- and six-coordinated ferroprotoporphyrin complexes in aqueous solution with or without detergent. For high-spin complexes having their iron atom monocoordinated to variously substituted imidazoles or to dimethylformamide, the frequency of a band observed between 194 and 237 cm⁻¹ (labelled band II) primarily depends on the <span><math><mtext>p</mtext><mtext>K</mtext><msub><mi></mi><mn><mtext>a</mtext></mn></msub></math></span> of the axial ligand. In the absence of steric effects from the axial ligand, the lower is the <span><math><mtext>p</mtext><mtext>K</mtext><msub><mi></mi><mn><mtext>a</mtext></mn></msub></math></span> of ligand, the higher the frequency of band II. We previously assigned band II to a mode essentially involving the Fe-N(pyrrole) bonds. The above <span><math><mtext>p</mtext><mtext>K</mtext><msub><mi></mi><mn><mtext>a</mtext></mn></msub></math></span> dependence is readily explained, in the frame of this assignment, in terms of a decrease in the Fe-N(pyrrole) bond strength (and of an increase in bond length) when the basicity of the axial ligand increases. On the other hand, the alternative assignment of band II to a stretching mode of Fe-N(axial ligand) is inconsistent with the observed <span><math><mtext>p</mtext><mtext>K</mtext><msub><mi></mi><mn><mtext>a</mtext></mn></msub></math></span> dependence. As far as hexacoordinated complexes are concerned, specific bands are observed at 203, 194 and 176 cm⁻¹ for imidazole, 1-methylimidazole and pyridine, respectively. These bands are assigned, on the basis of isotopic substitutions, to a summetric stretching mode of the axial ligands [ν(N-Fe-N)]. Band II is observed at 265 cm⁻¹ for these low-spin complexes, a frequency expected from the short Fe-N(pyrrole) bond lengths of nearly planar ferroporphyrins.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 2","pages":"Pages 168-176"},"PeriodicalIF":0.0,"publicationDate":"1981-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90131-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76324375","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}

{"title":"Purification and characterization of the two forms of human plasma α2HS-glycoprotein","authors":"Fumitake Gejyo,&nbsp;Karl Schmid","doi":"10.1016/0005-2795(81)90096-9","DOIUrl":"10.1016/0005-2795(81)90096-9","url":null,"abstract":"<div><p>The two forms of <span><math><mtext>α</mtext><msub><mi></mi><mn>2</mn></msub><mtext>HS-glycoprotein</mtext></math></span> were purified from Cohn fraction VI of normal human plasma and characterized in terms of their major chemical and physicochemical properties. Separation of these two proteins was achieved by chromatography on DEAE-cellulose at pH 4.4 followed by gel filtration through Sephadex G-100. The isoelectric points of the disc gel electrophoretically and immunochemically homogeneous glycoproteins were found to be at 4.1 and 4.7 and their apparent molecular weights, as determined by SDS-polyacrylamide gel electrophoresis, were shown to be 51 000 and 56 000, respectively. The amino acid compositions of both proteins were very similar, although differences, particularly in the arginine and histidine contents, were noted. The amino- and carboxyl-terminal amino acids were found to be the same for both proteins and were threonine and alanine, and valine and leucine, respectively, suggesting that both forms of this protein consist of two polypeptide chains. The total carbohydrate moiety of the relatively basic form (14%) proved to be comparable to that of the relatively acidic form (13%). More important, however, the sialic acid content of the latter was higher than that of the former. These results suggest that the difference between the two forms of <span><math><mtext>α</mtext><msub><mi></mi><mn>2</mn></msub><mtext>HS-glycoprotein</mtext></math></span> resides both in its carbohydrate and polypeptide moieties.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":"671 1","pages":"Pages 78-84"},"PeriodicalIF":0.0,"publicationDate":"1981-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90096-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17848575","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}