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1.
Red deer myoglobin has been fragmented by restricted tryptic digestion and by treatment with cyanogen bromide. The fragments have been separated by gel permeation. The core peptide derived from cyanogen bromide cleavage have been further digested with trypsin and the resulting peptides have been separated on Dowex 1X2. All fragments have been characterized by their amino acid composition, by determination of their N-terminal sequence using automatic Edman degradation and of their C-terminal sequence following the kinetics of amino acid cleavage by carboxypeptidases A and B. The complete sequence has been found to be identical with the already known sequence of sheep myoglobin except for residue 145 which is Gln in red deer globin and Glu in sheep globin. Reinvestigation of the corresponding sequence in sheep globin has shown that residue 145 of sheep globin is also Gln.  相似文献   

2.
The complete amino acid sequence of mohair protein, SCMKB-M1.2 (97 residues), was determined. The protein was isolated from reduced and carboxymethylated mohair by chromatography on DEAE-cellulose phosphate. Peptides for sequence determination were obtained by digestion with trypsin, pepsin, chymotrypsin, thermolysin and papain, and were fractionated by DEAE-cellulose chromatography, paper chromatography and electrophoresis. The sequence of the peptides were determined by the Edman degradation method (by use of both the Beckman Sequence and a non-automatic procedure), and by partial acid hydrolysis. The protein is closely homologous to wool protein SCMKB-IIIB2, and also contains acetylated alanine as N-terminal amino acid.  相似文献   

3.
The complete amino acid sequence of wool protein SCMKB-IIIB3 was determined. The peptides used for the sequence work were obtained by peptic and thermolysin digestions and were fractionated by chromatography on DEAE-cellulose, paper chromatography and electrophoresis. The peptides were analysed by dansyl-Edman degradation, mass spectrometry and tritium-labelling of C-terminal residues. The protein consists of 98 residues and has acetylalanine as N-terminal residue and carboxymethylcysteine as C-terminus. It is homologous with protein SCMKB-IIIB2 (Haylett & Swart, 1969). A salient feature of the sequence of protein SCMKB-IIIB3 is three consecutive cysteine residues.  相似文献   

4.
The primary structure of the myoglobin of the domestic dog (German shepherd) was studied. Tryptic and thermolytic peptides were compared with the sequence of other known myoglobins; the stepwise automatic Edman's degradation of the whole globin and also the chymotryptic digestion of the median fragment obtained by CNBr cleavage completed this sequence. Comparison of the established dog myoglobin structure with those from other carnivora shows 16 differences versus badger, 20 versus harbour seal and 15 versus California sea lion.  相似文献   

5.
Based on the amino acid composition of globin, amino acid analysis and N-terminal sequencing of peptides as well as a comparative analysis of the primary structure of beaver, coypu rat and otter myoglobins with the use of the fingerprinting technique, the amino acid sequence of the major component of ondatra myoglobin including 153 amino acid residues was reconstructed. The results of a comparative analysis of the primary structure of myoglobin and the peculiarities of the functional morphology of myoglobins from semi-aquatic animals and sperm whale and the role of amino acid substitutions in the spatial structure of ondatra myoglobin are discussed.  相似文献   

6.
The primary structure of human epidermal growth factor (hEGF), which was produced by Escherichia coli using recombinant DNA technique, has been studied by tandem mass spectrometry. The molecular weight of hEGF (about 6200 amu) was determined by fast atom bombardment mass spectrometry. Then reduced and carboxymethylated hEGF was digested by chymotrypsin into seven peptides which could cover the whole sequence of hEGF. The amino acid sequences of five of these seven peptides could be confirmed by tandem mass spectrometry with or without isolation by high-performance liquid chromatography (HPLC). After isolation by HPLC, the other two peptides were digested with trypsin or thermolysin into small peptides, and sequenced by tandem mass spectrometry.  相似文献   

7.
The complete amino acid sequences of wool protein SCMKB-IIIA3 (131 residues) and a minor component SCMKB-IIIA3A (130 residues) have been determined. The proteins are mutually homologous and have free threonine as the N-terminal residue and carboxymethylcysteine as the C-terminus. The peptides used for the sequence work were obtained by trypsin, thermolysin, pepsin and chymotrypsin digestions and were fractionated by chromatography on DEAE-cellulose, gel filtration on Sephadex G-25 and G-50, paper chromatography and electrophoresis. The Edman degradation method (employing both the Beckman Sequencer and a non-automatic procedure) was used to obtain the sequences of the peptides.  相似文献   

8.
Primary structure of chicken erythrocyte histone H2A   总被引:6,自引:0,他引:6  
The complete amino acid sequence (128 residues) of the chicken erythrocyte histone H2A was deduced from the data provided by structural studies on the tryptic peptides from the maleylated histone and of the peptides obtained by thermolysin digestion of the native protein. The sequence of chicken histone H2A differs from the calf homologous histone by the deletion of one residue of histidine at position 123 or 124 and three conservative substitutions: a residue of serine replaces a residue of threonine at position 16, a residue of aspartic acid replaces a residue of glutamic acid at position 121 and a residue of alanine replaces a residue of glycine at position 128.  相似文献   

9.
The complete amino acid sequence of the major component of hemoglobin from amur-leopard (Panthera pardus orientalis) is presented. The major component accounts for more than 90% of the total hemoglobin. Separation of the globin subunits was achieved by ion-exchange chromatography on CM-cellulose in urea. The sequence was studied by automatic Edman degradation of tryptic and hydrolytic peptides. Alignment was carried out with human hemoglobin sequence. The β NH2 terminus is blocked with Ac-serine. The data are compared with other mammalian hemoglobins and results are discussed with respect to sequence and physiology.  相似文献   

10.
The neutral protease of Bacillus subtilis var. amylosacchariticus was cleaved chemically or digested with proteolytic enzymes, and the resultant peptides were separated and purified by high performance liquid chromatography. The sequence analyses of these peptides by the manual Edman procedure established the complete amino acid sequence of the enzyme. The neutral protease consisted of 300 amino acid residues with Ala and Leu as its amino- and carboxyl-termini, respectively, and the molecular weight was calculated to be 32,633. The sequence was found to be identical to that of B. subtilis 1A72 neutral protease, which was deduced from nucleotide sequencing. Comparison of the sequence with those of other Bacillus proteases revealed that the putative active site amino acid residues, Zn-binding ligands, and two Ca-binding sites were well conserved among them, as compared with those of thermolysin.  相似文献   

11.
The complete amino acid sequence of the A-chain of major hemoglobin component from gray partridgeFrancolinus pondacerianus is presented. The major component HbA accounts for 75% of the total hemolysate. Separation of the globin subunits was achieved by ion-exchange chromatography on CM-Cellulose in 8 M urea. The sequence was studied by automatic Edman degradation of the native chain and its tryptic peptides in a gas-phase sequencer. The phylogenetic relationship of Galliformes with other avian orders is discussed.  相似文献   

12.
C Y Yang  W Y Huang  S Chirala  S J Wakil 《Biochemistry》1988,27(20):7773-7777
The complete amino acid sequence of thioesterase domain of chicken liver fatty acid synthase has been determined by sequencing peptides produced by trypsin, Staphylococcus aureus V8 protease, and cyanogen bromide cleavage. The thioesterase domain consists of 300 amino acid residues. All of the tryptic peptides of the thioesterase domain were isolated and sequenced, except the segment covered from position 109 to position 124. Peptides resulting from digestion by Staphylococcus aureus V8 protease and cyanogen bromide cleavage filled the missing part and overlapped the complete sequence of the entire thioesterase domain. The NH2 terminus of the thioesterase domain was determined to be lysine by sequencing the whole domain up to 20 residues while the COOH terminus was identified as serine through carboxyl peptidase Y cleavage. The active site of the thioesterase domain of chicken fatty acid synthase was suggested to be the serine on position 101 according to its homology with other serine-type esterases and proteases which have a common structure of -Gly-X-Ser-Y-Gly- with the variable amino acids X and Y disrupting the homology.  相似文献   

13.
The complete amino acid sequence of the major component myoglobin from the Pacific spotted dolphin, Stenella attenuata graffmani, was determined by the automated Edman degradation of several large peptides obtained by specific cleavage of the protein. The acetimidated apomyoglobin was selectively cleaved at its two methionyl residues with cyanogen bromide and at its three arginyl residues by trypsin. By subjecting four of these peptides and the apomyoglobin to automated Edman degradation, over 80% of the primary structure of the protein was obtained. The remainder of the covalent structure was determined by the sequence analysis of peptides that resulted from further digestion of the central cyanogen bromide fragment. This fragment was cleaved at its glutamyl residues with staphylococcal protease and its lysyl residues with trypsin. The action of trypsin was restricted to the lysyl residues by chemical modification of the single arginyl residue of the fragment with 1,2-cyclohexanedione. The primary structure of this myoglobin proved to be identical with that from the Atlantic bottlenosed dolphin and Pacific common dolphin but differs from the myoglobins of the killer whale and pilot whale at two positions. The above sequence identities and differences reflect the close taxonomic relationship of these five species of Cetacea.  相似文献   

14.
Peptides obtained as a result of cyanogen bromide cleavage of the G-factor have been studied. All 12 peptides embracing the whole structure of fragment T4 have been isolated. For their amino acid sequence determination, cyanogen bromide peptides have been further cleaved with trypsin, chymotrypsin, thermolysin, staphylococcal glutamic protease and BNPS-skatole. The complete primary structure of 9 from 12 cyanogen bromide peptides has been determined.  相似文献   

15.
The complete amino acid sequence of the major component myoglobin from finback whale, Balaenoptera physalus, was determined by the automated Edman degradation of several large peptides obtained by specific cleavages of the protein. Three easily separable peptides were obtained by cleaving with cyanogen bromide at the two methionine residues and one large peptide was isolated after cleavage with (2-p-nitrophenylsulfenyl)-3-methyl-3'-bromoindolenine. More than 60% of the covalent structure was established by the sequential degradation of three of these peptides and the apomyoglobin. An additional 30% of the primary sequence was established with peptides obtained from tryptic digestion of both the apomyoglobin and the acetimidoapomyoglobin, and the final 10% of the sequence was completed after digestion of the two larger cyanogen bromide peptides with S. aureus strain V8 protease. This myoglobin differs from that of the sperm whale, Physeter catodon, at 15 positions, from that of the arctic minke whale, Balaenoptera acutorostrata, at 3 positions, and from that of the California gray whale, Eschrichtius gibbosus, at 4 positions. All of the substitutions observed in this sequence fit easily into the three-dimensional structure of the sperm whale myoglobin.  相似文献   

16.
The globin derived from the monomer Component IV hemoglobin of the marine annelid,Glycera dibranchiata, has been completely sequenced, and the resulting information has been used to create a structural model of the protein. The most important result is that the consensus sequence of Component IV differs by 3 amino acids from a cDNA-predicted amino acid sequence thought earlier to encode the Component IV hemoglobin. This work reveals that the histidine (E7), typical of most heme-containing globins, is replaced by leucine in Component IV. Also significant is that this sequence is not identical to any of the previously reportedGlycera dibranchiata monomer hemoglobin sequences, including the sequence from a previously reported crystal structure, but has high identity to all. A three-dimensional structual model for monomer Component IV hemoglobin was constructed using the published 1.5 å crystal structure of a monomer hemoglobin fromGlycera dibranchiata as a template. The model shows several interesting features: (1) a Phe31 (B10) that is positioned in the active site; (2) a His39 occurs in an interhelical region occupied by Pro in 98.2% of reported globin sequences; and (3) a Met41 is found at a position that emerges from this work as a previously unrecognized heme contact.Abbreviations used GMHX the holo-protein (including b-type heme, Glycera dibranchiata monomer hemoglobin Component X (X=2, 3, or 4) - GMGX the apo-protein, or globin, Glycera dibranchiata monomer globin derived from Component X (X=2, 3, or 4) - rec-gmg the globin derived from a recombinant holoprotein of a Glycera dibranchiata monomer hemoglobin, rec-gmh, whose sequence has been inferred from an isolated cDNA insert - CB label refers to peptides generated from cyanogen bromide cleavage of GMG4 - HPLC high-performance liquid chromatography - T label refers to peptides generated from trypsin digests of GMG4 - Mb myoglobin - MCS monomer hemoglobin crystal structure from Glycera dibranchiata. H, N-terminal sequence of GMG4 - SWMb sperm whale myoglobin  相似文献   

17.
The experimental details which led to the determination of the complete primary structure of protein S13 from the small subunit of Escherichia coli ribosomes are presented. S13 consists of 117 amino acid residues and has the following composition: Asp6, Asn2, Thr6, Ser6, Glu6, Gln2, Pro4, Gly11, Ala11, Cys1, Val7, Met2, Ile12, Leu9, Tyr2, Phe1, His3, Lys11 and Arg15. Tryptophan was not found. The molecular weight of protein S13 as derived from the sequence shown in Fig. 1 is 12970. The amino acid sequence of the protein was determined by combining the results obtained from liquid phase Edman degradation of the intact protein with those from the peptides isolated after enzymatic digestions with trypsin, Staphylococcus aureus protease and thermolysin. Additional information about the primary structure was derived from analysis of the chymotryptic peptides of protein S13 and from its digestion with carboxypeptidase C. The amino acid sequence of protein S13 was compared with the published sequences of the other ribosomal proteins of E. coli and predictions for the secondary structure of this protein were made.  相似文献   

18.
Type V collagen was prepared from human amnionic/chorionic membranes and separated into alpha 1(V) and alpha 2(V) polypeptide chains. The alpha 1(V) chain was digested with cyanogen bromide and nine peptides were obtained and purified. Three of the peptides, alpha 1(V)CB1, CB4, and CB7 having molecular weights of 5000, 8000, and 6000, respectively, were further analyzed by amino acid sequence analysis and thermolytic or tryptic digestions. CB1 contained 54 amino acids and identification of its complete sequence was aided by thermolysin digestion and isolation of two peptides, Th1 and Th2. CB4 contained 81 amino acids and sequence analysis of intact CB4 and five tryptic peptides provided us with its complete amino acid sequence. The peptide CB7 contained 67 amino acids and was cleaved into four tryptic peptides that were used for complete sequence analysis. The above results represent the first available covalent structure information on the alpha 1(V) collagen chain. These data enabled us to establish the location of these peptides within the helical structure of other collagen chains. CB4 was homologous to residues 66-145 in the collagen chain while CB1 represented residues 146-200 and CB7 was homologous with residues 201-269. This alignment was facilitated by identification of a helical collagen crossing site consisting of Hyl-Gly-His-Arg located at positions 87-90 in all collagen chains of this size thus far identified. Seventy-one percent homology (excluding Gly residues) was found between amino acids in this region of the alpha 1(XI) and of alpha 1(V) collagen chains while only 21 and 19% identity was calculated for the same region of alpha 2(V) and alpha 1(I) collagen chains, respectively.  相似文献   

19.
L Fryklund  D Eaker 《Biochemistry》1975,14(13):2865-2871
The complete covalent structure of a small, basic protein with cardiotoxic activity is described. This has been isolated from the venom of Naja nigricollis by gel filtration on Sephadex G-75 and gradient ion exchange chromatography on Bio-Rex 70. The cardiotoxin, molecular weight 6806 from amino acid composition, consists of 60 amino acids, cross-linked by four disulfide bridges, connecting 3-21, 14-38, 42-53, and 54-59. The protein contains one residue of tryptophan, phenylalanine, and glutamic acid, two residues of arginine and tyrosine, four residues of methionine, and nine residues of lysine. Histidine is absent. The chymotryptic peptides of the oxidized and S-carboxymethylated protein were isolated by gel filtration on Sephadex G-25 and zone electrophoresis on a cellulose column. The sequence was determined by Edman degradation, using the (manual) direct phenylthiohydantoin method and with the use of carboxypeptidase A. Disulfide pairing was determined on thermolysin cleaved peptides from the native protein. The sequence is shown to be homologous to other cardiotoxins and a lytic factor from snake venoms and also shows homology, both in sequence and disulfide pairing to neurotoxins. A partial reduction experiment in the absence of denaturing agent using 14-C-labeled iodoacetic acid as S-carboxymethylating agent shows that disulfide bonds 14-38 and 42-53 were reduced fastest followed marginally by 54-59, and then bond 3-21.  相似文献   

20.
The primary structure of L-asparaginase from Escherichia coli   总被引:1,自引:0,他引:1  
The carboxymethylated L-asparaginase from Escherichia coli A-1--3 was fragmented with cyanogen bromide and the resulting peptides were isolated by using gel filtration on Sephadex G-50 and column chromatography on DE-52. The amino acid sequences of the 7 cyanogen bromide peptides thus obtained were established completely or partially by further fragmentation with trypsin, chymotrypsin and pepsin, and the Dansyl Edman method. Based on the above results and the complete sequences of the tryptic peptides from the carboxymethylated L-asparaginase reported in the previous paper, the whole sequence of the enzyme was established. The reported sequence consists of 321 amino acid residues and its calculated molecular weight is 34 080.  相似文献   

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