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1.
S-Carboxymethylated L-asparaginase was digested with trypsin and the resulting peptides were isolated by using gel filtration, ion exchange column chromatography and paper chromatography. Among the peptides thus isolated, 27 peptides were considered not to overlap and the sum of the amino acids from these 27 peptides is in good agreement with amino acid composition of the enzyme. The amino acid sequences of the peptides were determined by fragmentation with various enzymes and subtractive Edman degradation.  相似文献   

2.
We describe a peptide sequencing procedure which can be used to verify an amino acid sequence which is derived from a nucleotide sequence. One first labels the protein with a 3H- and a 14C-labelled amino acid and then cleaves the protein into a set of peptides using a cleavage reaction specific for a particular amino acid residue. Finally one performs Edman degradations on the whole mixture of peptides. The released amino acids reflect the combined aminoterminal amino acid sequences of all the peptides that have been formed by the cleavage reaction. The data can therefore be used to check a deduced sequence simultaneously at several regions of the polypeptide chain. We have applied this sequencing procedure to verify the amino acid sequence deduced from the 26S RNA of Semliki Forest virus.  相似文献   

3.
The amino acid sequence of beta-galactosidase has been determined. The monomer contains 1,021 amino acid residues in a single polypeptide chain and has a molecular weight of 116,349. All 80 tryptic peptides as well as all 24 CNBr peptides have been isolated in pure form. Evidence is presented for the ordering of the CNBr peptides. The sequence determination was aided by analysis of cyanogen bromide peptides obtained from a polypeptide fragment produced by a lacZ termination mutant strain.  相似文献   

4.
Antithrombin Northwick Park and antithrombin Glasgow are functionally variant antithrombins with impaired abilities to interact with thrombin. Thrombosis is associated with their inheritance. Both of the purified, reduced, and S-carboxymethylated variant antithrombins were treated with cyanogen bromide and the major pools of each containing the amino acid sequence Gly339-Met423 were isolated. Following treatment of these pools with trypsin, fast atom bombardment mass spectrometry identified tryptic peptides (found also in normal antithrombin treated in the same way) that corresponded to amino acid sequences Gly339-Lys370 and Val400-Met423. The tryptic peptides, corresponding to amino acid sequences Ala371-Arg393 and Ser394-Arg399 were present in both variant preparations in greatly reduced amounts compared to a normal antithrombin preparation. However, two novel tryptic peptides of molecular mass (M + H)+ 2976 and 2952 were identified in the digests of antithrombin Northwick Park and Glasgow, respectively. Further analyses of these novel tryptic peptides were carried out by V8 protease treatment and sequential Edman degradation coupled with mass spectrometric analysis of the shortened peptides. This established that these peptides comprised the amino acid sequence Ala371-Arg399, but with single amino acid substitutions at the reactive site, Arg393 replaced by Cys (in antithrombin Northwick Park) and by His (in antithrombin Glasgow).  相似文献   

5.
D-Amino acid oxidase from pig kidney cortex was digested with trypsin. Thirty-two tryptic peptides were isolated by ion exchange chromatography, high voltage paper electrophoresis, descending paper chromatography, and reverse-phase high performance liquid chromatography. The last method permitted the isolation of 29 tryptic peptides, many in a single step, in yields usually greater than 75%. The purified peptides were characterized by amino acid analysis and their sequences determined by the manual 5-dimethylaminonaphthalene-1-sulfonyl-Edman degradation procedure or by the automated Edman-Begg degradation method. These peptides accounted for all 12 lysine and 21 arginine residues observed by amino acid analysis of the intact protein and for 347 amino acid residues of the 345 predicted by the analysis.  相似文献   

6.
As a part of the elucidation of the complete amino acid sequence of human phosphoglycerate kinase, 46 tryptic peptides, ranging in length from 1 to 26 residues, were isolated and characterized from the reduced and S-carboxymethylated enzyme. The isolated peptides were subjected to sequence analysis by the modified dansyl-Edman degradation procedure and automated Edman degradation technique. The results, together with the data on cyanogen bromide peptides and two additional tryptic peptides from cyanogen bromide peptides reported in the accompanying paper, established the complete amino acid sequence of human erythrocyte phosphoglycerate kinase.  相似文献   

7.
The beta subunit of follicle-stimulating hormone (FSH-beta) from human pituitary glands was reduced and S-aminoethylated prior to thermolytic, tryptic, and chymotryptic digestions. Each digest was gel-filtered on Sephadex G-50 to seperate the glycopeptides. The glycopeptides and the peptides were isolated by high voltage paper electrophoresis at pH 6, 3.5, and 2.0. The purity of the isolated peptides was confirmed by amino acid analyses. The amino acid sequences of peptides were determined by Edman degradation followed by subtractive amino acid analysis and, in certain cases, confirmed by dansylation. COOH-terminal sequences of the peptides were determined by digestion with carboxypeptidases A and B and by hydrazinolysis. The tryptophan content of human follicle-stimulating hormone, of the beta subunit of human follicle-stimulating hormone, and of the glycopeptides obtained from the enzymic digests was determined by fluorescence spectra, titration against N-bromosuccinimide, colorimetric estimation with p-dimethyl aminobenzaldehyde, hydrolysis with methane sulfonic acid containing 0.2% tryptamine followed by amino acid analysis, microbiological assay, and sequence analysis. The presence of 1 tryptophan residue in the beta subunit was indicated.  相似文献   

8.
Follicle-stimulating hormone of a high state of physicochemical and biological purity was isolated from acetone-preserved human pituitary glands. The follicle-stimulating hormone was dissociated into alpha and beta subunits by treatment with 8 M urea and the subunits were separated by ion exchange chromatography on DEAE-Sephadex A-25. The subunits were freed of undissociated or reassociated follicle-stimulating hormone by gel filtration on Sephadex G-100. For the establishment of the primary amino acid sequence, the alpha subunit was reduced and either carboxyamidomethylated or S-aminoethylated prior to a thermolytic or a tryptic digestion. Each digest was gel filtered on a column of Sephadex G-50 to separate the glycopeptides from the peptides. The glycopeptides and the peptides were purified further by sequential gel filtration on Sephadex G-25, G-15, and Bio-Gel-P-2 and were isolated by high voltage electrophoresis at pH 6, 3.5, and 2. The purity of the isolated peptides was ascertained further by amino acid analysis. The amino acid sequences of the peptides were determined by Edman degradation followed by subtractive amino acid analysis. COOH-terminal sequences were established by digestion with carboxypeptidases A and B. The primary amino acid sequence of human follicle-stimulating hormone-alpha is identical to that of human chorionic gonadotropin-alpha and differs from that of human luteinizing hormone-alpha in having the tripeptide Ala-Pro-Asx- at the NH2-terminal end.  相似文献   

9.
Structure of the antitumor protein neocarzinostatin. Amino acid sequence   总被引:1,自引:0,他引:1  
The amino acid sequence of the antitumor protein neocarzinostatin has been proposed, as shown in Fig. 7, by sequence analysis of tryptic peptides and fragments obtained by digestion of the protein with chymotrypsin, pepsin, acid protease, and dilute hydrochloric acid. Neocarzinostatin consists of 109 amino acid residues and its molecular weight, calculated from the proposed structure, is 10,717.  相似文献   

10.
The effect of single amino acid substitutions at positions 18 and 20 on the T-cell determinant (TD) character of peptide p12-26 from lambda repressor protein and on its recognition by a monoclonal antibody was studied by means of 40 synthetic peptides of a length of 15 amino acids. ELISA competition experiments showed that the identity of amino acid at position 20 is very important for antibody recognition, whereas that of amino acid at position 18 is much less important. In contrast, both Leu 18 and Ala 20 are important residues in defining the TD character of peptide p12-26. The most tolerated replacements, ordered in increasing disrupting power are: Ala 20 by Cys, Ser or Gly and Leu 18 by Ile or Val. Any other amino acid replacement completely abolishes the TD capacity of peptide p12-26. The peptides used in this study were synthesized using a multiple solid-phase peptide synthesizer newly designed. Their purity was very high as shown by amino acid sequence experiments.  相似文献   

11.
The alignment of all the CNBr-cleavage peptides of fragment Bb from human Factor B (a component of the alternative pathway of complement) was determined. This was derived from cleavage of the fragment Bb at arginine residues by using trypsin and clostripain. Details of the isolation and amino acid sequences of these peptides are given. Together with previously published N-terminal sequences of the CNBr-cleavage peptides [Christie & Gagnon (1982) Biochem. J. 201, 555-567], this provides the amino acid sequence of the N-terminal half of fragment Bb.  相似文献   

12.
In order to elucidate the complete amino acid sequence of Pseudomonas putida cytochrome P-450, tryptic digestion was performed on the S-carboxymethylated enzyme. Although cleavage did not occur at every lysyl and arginyl bond, 31 tryptic peptides ranging in size from 1 to 55 residues were isolated. These were sequenced by manual Edman degradation and carboxypeptidase digestion. Overlaps of some od these tryptic peptides were obtained by data obtained from partial Edman degradation and amino acid composition of the clostripain cleavage products. These results, together with data from the cyanogen bromide and acid cleavage peptides reported in the accompanying paper, established the complete amino acid sequence of P. putida cytochrome P-450.  相似文献   

13.
The amino acid sequence of the C-terminal domain of the elongation factor G (EF-G) has been studied. The polypeptide chain of the domain consists of 228 amino acid residues, and contains no tryptophan or cysteine residues. To determine its structure, the peptides obtained as a result of the fragment digestion by staphylococcal glutamic protease, cyanogen bromide cleavage, and tryptic hydrolysis of the fragment modified by maleic anhydride have been analyzed, as well as peptides obtained after hydrolyses of cyanogen bromide fragments with chymotrypsin, thermolysin and trypsin.  相似文献   

14.
The peptides which result from treatment of the S-[14C]carboxymethyl derivative of dogfish M4 lactate dehydrogenase (EC 1.1.1.27) with trypsin have been isolated and their sequences have been elucidated. Each identical subunit has a molecular weight of 36,000 and on the basis of the amino acid composition 40 unique tryptic peptides are anticipated. Thirty-seven of these peptides have been isolated and have been completely characterized. The amino acid sequences of these peptides are presented.  相似文献   

15.
Globin prepared from hemoglobin of the brown lemur (Lemur fulvus fulvus) was separated into alpha and beta chains by chromatography on a CM 52 column. The S-aminoethylated alpha and beta chains were each digested with trypsin and resulting peptides were isolated. The amino acid sequences of the tryptic peptides were established. The ordering of these peptides in the alpha and beta chains was deduced from the homology of their amino acid sequences with that of human adult hemoglobin. The primary structure of brown lemur hemoglobin thus obtained differs from that of human hemoglobin in 15 amino acids in the alpha chain and 26 in the beta chain.  相似文献   

16.
The synthesis of a conformationally constrained photoisomerizable amino acid, phenylazo-1,2,3,4-tetrahydro-3-isoquinolinecarboxylic acid (PATIC), is described. This amino acid can be incorporated into peptides using standard Fmoc procedures and can be accommodated within alpha-helical structures albeit with some loss of stability of the structure. PATIC can serve as a useful building block for the synthesis of photoregulated peptides and proteins.  相似文献   

17.
Amino acid sequence of chitinase from Streptomyces erythraeus   总被引:2,自引:0,他引:2  
The amino acid sequence of chitinase from Streptomyces erythraeus was determined by the conventional method. The amino acid sequences of tryptic peptides of the reduced and S-carboxymethylated protein were determined. The tryptic peptides were aligned by overlapping the amino acid sequences of chymotryptic peptides, lysyl endopeptidase peptides and cyanogen bromide fragments. S. erythraeus chitinase consists of 290 amino acid residues with the molecular weight of 30,400 and has two disulfide bridges at Cys(45)-Cys(89) and Cys(265)-Cys(272). The enzyme has no significant homology with other chitinases, lysozymes, and other proteins.  相似文献   

18.
The sequence determination of polypeptide VII from beef heart cytochrome c oxidase is described. The amino acid sequence is deduced from overlapping tryptic peptides and peptides obtained after cleavage with Staphylococcus aureus protease. The protein consists of 85 amino acids corresponding to a Mr of 10026, in agreement with a value of 9500 obtained by sodium dodecyl sulfate gel electrophoresis. The amino acid sequence around the only methionine present is very similar to sequences around the invariant heme binding methionine of the cytochrome c family. This similarity suggests that the protein is one of the heme bindings subunits of the oxidase.  相似文献   

19.
J P van Eerd  K Takahshi 《Biochemistry》1976,15(5):1171-1180
The amino acid sequence of bovine cardiac troponin C has been completely determined. The protein was cleaved by cyanogen bromide and the resulting peptides were isolated. All of the 161 residues of the protein could be accounted for in 12 cyanogen bromide peptides. Overlapping peptides were generated by tryptic digestion of citraconylated troponin C and isolation of the resulting five peptides. The primary structure of cardiac troponin C was elucidated by sequential manual Edman degradation of these peptides. It consists of four homologous regions, one of which probably has lost the ability to bind calcium ions. By comparing the amino acid sequence of cardiac troponin C with the sequence of skeletal troponin C, it was found that the mutation rate of the region that does not bind calcium is almost twice as high as the mutation rate of the three homologous regions that do bind calcium.  相似文献   

20.
The partial amino acid sequence of pooled, microheterogeneous pig immunoglobulin lambda chains was determined previously (Fran?k, F. (1970), FEBS Lett. 8, 269; Novotny, J., and Fran?k, F. (1975), FEBS Lett. 58, 24). In the present study, citraconylated pig lambda chains were digested by trypsin under conditions in which some of the epsilon-amino groups of lysine residues unmask. The resulting fragments were purified by gel filtration and ion-exchange chromatography at pH 3.0 in buffers containing urea; some of the fragments were found to be of intermediate size (i.e., larger than normal tryptic peptides but smaller than "citraconyl" peptides), thus permitting overlap information and amino acid sequences of all the 14 tryptic peptides to be deduced from amino acid compositions and partial amino acid sequences of selected fragments. In addition to completing the major amino acid sequence of pig immunoglobulin lambda chains, the present study demonstrates that it is possible to sequence microheterogeneous proteins with a suitable fragmentation strategy.  相似文献   

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