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1.
Maleilated histidine decarboxylase beta-polypeptide chain, containing 3 arginine residue, was hydrolysed by trypsin. 4 non-overlapping homogenous peptides were isolated, 3 of them containing one arginine residue and the 4th peptide being C-terminal fragment of beta-chain. beta-Polypeptide chain is found to consist of 78 amino acid residues and to have molecular weight of 8456. Primary structure of each peptide and their possible sequence in beta-chain are determined.  相似文献   

2.
Two low molecular weight peptide inhibitors of medullasin were isolated from human bone marrow cells. Determination of their amino acid composition and amino acid sequence revealed that one inhibitor was composed of 36 amino acid residues and the other 34 amino acid residues which are identical with the C-terminal portions (Formula; see text) of the beta-chain of human hemoglobin. These two peptides when synthesized also showed the same degree of inhibitory effect on medullasin activity as the natural products. Neither the N-terminal portion of the inhibitor, composed of 21 amino residues, nor the C-terminal peptide, composed of 20 amino acids, inhibited medullasin activity. Medullasin was inhibited reversibly and non-competitively against by these inhibitors and was the most effectively inhibited serine protease among several tested.  相似文献   

3.
The complete amino acid sequence of a sweet-taste-suppressing peptide, gurmarin, from the leaves of Gymnema sylvestre was determined by the Edman analysis of peptides derived from digests obtained with Staphylococcus aureus V8 protease, pyroglutamyl aminopeptidase, and lysyl endopeptidase. Gurmarin consists of 35 amino acid residues with an amino-terminal pyroglutamyl residue and has the molecular weight of 4,209. Gurmarin has no significant homology with other known proteins.  相似文献   

4.
The primary structure of ribonuclease F1 from Fusarium moniliforme   总被引:1,自引:0,他引:1  
The primary structure of ribonuclease F1, the guanine specific ribonuclease from Fusarium moniliforme, has been determined. Ribonuclease F1 consists of 106 amino acid residues and has a molecular weight of 10,980. It has a pyroglutamyl residue at the N-terminus. Comparison of the primary structures of four fungal ribonucleases so far sequenced shows that the amino acid sequences around the assumed active site residues are indeed well conserved. However, structurally important half cystine residues are arranged variously.  相似文献   

5.
The amino acid sequence of the beta-chain of the principal haemoglobin from the shark H. portusjacksoni has been determined. The chain has 141 residues, the same as that of mammalian alpha-chains and less than the 146 residues of mammalian beta-chains or the 148 residues of the alpha-chain from the tetrameric shark haemoglobin. The sequence was deduced from the sequences of peptides obtained by digestion of the globin or its cyanogen bromide fragments with trypsin, chymotrypsin, pepsin and papain. The difference in length of the beta-chain is most readily accounted for by the absence of the D helix. This small helical section is normally present in myoglobins and beta-globins but absent in alpha-chains. The deduction that it is absent from shark beta-chain is based on consideration of homology. The beta-chain shows the insertion of histidine beta2 and the deletions corresponding to residues A17 and AB1 relative to alpha-and myoglobin chains. The reactive thiol group in shark haemoglobin was shown by radioactive labelling to be residue 51 in the beta-chain, immediately preceding the E helix. The amino acid sequence of shark beta-chain shows 92 differences from human beta-chain, significantly more differences than shown by chicken or frog beta-chains, in line with its earlier time of divergence. If the tertiary structure of the shark beta-chain is the same as that of the horse then there are two changes in the alpha1beta2 contact site in oxyhaemoglobin and an additional one in deoxyhaemoglobin. When both alpha- and beta-chain contacts are considered there is a total of nine changes in residues involved in the alpha1beta2 contacts. There is no Bohr effect in shark haemoglobin, and of the residues normally involved in this effect the C-terminal histidine residue of the beta-chain is present, but the aspartyl (FG1) residue to which it is salt-linked is not, being replaced by a glutamyl residue.  相似文献   

6.
1. Partial amino acid sequences for several sockeye salmon hemoglobin beta-chains have been determined and compared to several other fish beta-chain sequences. 2. A 90% homology exists between the sockeye cathodal (C1) beta-chain and the trout Hb I beta-chain for residues 1-19. 3. The sockeye salmon anodal (A1-3) beta-chain is virtually identical to the trout HB IV beta-chain for the first 55 amino acid residues. 4. The alpha-chains of the sockeye salmon appear to be acetylated at the N-terminal position and about 0.6% of the sockeye hemoglobin is glycosylated.  相似文献   

7.
We have isolated two overlapping cDNA clones that encompass the entire structural gene for pyruvate, orthophosphate dikinase from maize. The analysis of the nucleotide sequence has revealed that the cDNA clones include an insert of a total of 3,171 nucleotides without a poly(A) tail and encode a polypeptide that contains 947 amino acid residues and has a molecular weight of 102,673. Comparison of the N-terminal amino acid sequence of purified pyruvate, orthophosphate dikinase protein with that deduced from the nucleotide sequence shows that the mature form of pyruvate, orthophosphate dikinase in the maize chloroplast consists of 876 amino acid residues and has a molecular weight of 95,353. The amino acid composition of the deduced sequence of pyruvate, orthophosphate dikinase is in good agreement with that of the purified enzyme. The region that contains the active and regulatory sites of pyruvate, orthophosphate dikinase can be found in the deduced sequence of amino acids. We have predicted the secondary structure and calculated the hydropathy pattern of this region. The extra 71 residues at the N terminus of the deduced sequence of amino acid residues corresponds to the transit peptide which is indispensable for the transport of the precursor protein into chloroplasts. We have compared the primary structure of the pyruvate, orthophosphate dikinase transit peptide to those of other proteins and found sequences similar to the consensus sequences found in other transit peptides.  相似文献   

8.
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   

9.
The complete amino acid sequence of the heme alpha-containing subunit V of bovine heart cytochrome oxidase was determined to be: H2N-Ser-His-Gly-Ser-His-Glu-Thr-Asp-Glu-Glu-Phe-Asp-Ala-Arg-Trp-Val-Thr-Tyr-Phe-Asn-Lys-Pro-Asp-Ile-Asp-Ala-Trp-Glu-Leu-Arg-Lys-Gly-Met-Asn-Thr-Leu-Val-Gly-Tyr-Asp-Leu-Val-Pro-Glu-Pro-Lys-Ile-Ile-Asp-Ala-Ala-Leu-Arg-Ala-Cys-Arg-Arg-Leu-Asn-Asp-Phe-Ala-Ser-Ala-Val-Arg-Ile-Leu-Glu-Val-Val-Lys-Asp-Lys-Ala-Gly-Pro-His-Lys-Glu-Ile-Tyr-Pro-Tyr-Val-Ile-Gln-Glu-Leu-Arg-Pro-Thr-Leu-Asn-Glu-Leu-Gly-Ile-Ser-Thr-Pro-Glu-Glu-Leu-Gly-Leu-Asp-Lys-Val-COOH. The subunit V is a single polypeptide which consists of 109 amino acid residues. The protein contains 48.6% hydrophobic residues and 34.0% hydrophilic residues and it is an acidic protein having a net charge of -3 at neutral pH. The molecular weight of subunit V was calculated to be 12,436 and that for the heme alpha-containing polypeptide was 13,295.  相似文献   

10.
The extracellular elastase (33 kDa) of Pseudomonas aeruginosa is synthesized as a 53.6 kDa preproenzyme containing a long, N-terminal propeptide. The free propeptide and the elastase precursor generated upon propeptide removal were isolated from P. aeruginosa cells and subjected to N-terminal amino acid sequence analysis. The results identified Ala-174 and Ala+1 as the amino terminal residues of the propeptide and the elastase precursor, respectively, indicating that: (1) the signal peptide consists of 23 amino acid residues and its molecular weight is 2.4 kDa, (2) the propeptide contains 174 amino acid residues and is of 18.1 kDa molecular weight, and (3) no additional N-terminal proteolytic cleavage is required for elastase maturation.  相似文献   

11.
广西眼镜蛇毒磷酸二酯酶分离纯化及部分性质   总被引:4,自引:0,他引:4  
磷酸二酯酶(PDE)广泛存在于各种蛇毒中,在响尾蛇科、蝰蛇科、眼镜蛇科和海蛇科的部分蛇毒中都存在着该酶.不同的蛇毒其PDE活力及含量有很大差异.即便在生物学分类上十分接近的蛇种,其PDE活力亦相差甚远.该酶是核酸结构分析的一种重要工具酶,具有核酸水解酶作用,是一种核酸外切酶,它能从3'-端顺序地降解核糖或脱氧核糖多核苷酸,生成5'-单核苷酸.该酶既能水解DNA又能水解RNA,因而在核酸的鉴定和序列测定方面获得了广泛的应用.由于蛇毒PDE在核酸顺序测定中显示的重要性,因而对各种蛇毒纯化PDE的研究工作引起了国内外学者的广泛兴趣.王殿洪等[1]曾对江西蝮蛇毒中PDE的分离纯化及某些性质做过报道,但广西眼镜蛇毒中PDE的分离纯化及性质在国内外均未有报道.广西有丰富的眼镜蛇毒资源,而且有高活性的PDE.蛇毒PDE的生物学活性,国外研究得较少.它没有出血、凝血、纤溶及致死作用.蛇毒PDE水解核糖核酸产生5'-单核苷酸,5'-单核苷酸在医药上均有十分重要作用,制成药物治疗白血病和血小板减少症等.  相似文献   

12.
Two acylphosphatase molecular forms have been isolated from bovine testis. Their amino acid sequence was determined. One (ACY1) consists of 98 amino acid residues, while the other one (ACY2) consists of 100 amino acid residues. Both molecular forms are N-acetylated and differ only in the amino terminus. ACY2 has an additional Ser-Met tail with respect to ACY1. Both ACY1 and ACY2 are organ-common type isoenzymes and thus differ for about half of the amino acid positions from the previously sequenced bovine muscle isoenzyme.  相似文献   

13.
A new bacteriocin has been isolated from an Enterococcus faecium strain. The bacteriocin, termed enterocin A, was purified to homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, N-terminal amino acid sequencing, and mass spectrometry analysis. By combining the data obtained from amino acid and DNA sequencing, the primary structure of enterocin A was determined. It consists of 47 amino acid residues, and the molecular weight was calculated to be 4,829, assuming that the four cysteine residues form intramolecular disulfide bridges. This molecular weight was confirmed by mass spectrometry analysis. The amino acid sequence of enterocin A shared significant homology with a group of bacteriocins (now termed pediocin-like bacteriocins) isolated from a variety of lactic acid-producing bacteria, which include members of the genera Lactobacillus, Pediococcus, Leuconostoc, and Carnobacterium. Sequencing of the structural gene of enterocin A, which is located on the bacterial chromosome, revealed an N-terminal leader sequence of 18 amino acid residues, which was removed during the maturation process. The enterocin A leader belongs to the double-glycine leaders which are found among most other small nonlantibiotic bacteriocins, some lantibiotics, and colicin V. Downstream of the enterocin A gene was located a second open reading frame, encoding a putative protein of 103 amino acid residues. This gene may encode the immunity factor of enterocin A, and it shares 40% identity with a similar open reading frame in the operon of leucocin AUL 187, another pediocin-like bacteriocin.  相似文献   

14.
Following the previous determination of the main variant H1b of human spleen histone H1, we have determined the complete amino acid sequence of another variant, H1d. Limited chymotryptic digestion of H1d produced four fragments, I to IV, and one partial fragment I-II, as in the case of H1b. These fragments were aligned with two overlapping peptides, produced by another enzyme from the intact H1d. We also confirmed the C-terminal sequence of H1d by carboxypeptidase digestion. This H1d has an acetylated N-terminal serine, equimolar alanine or valine residue at 17, and is composed of 212 residues. The molecular weight was 21,233 for the alanine variant and 21,261 for the valine variant in the unmodified form. We also deduced the total sequences of H1a and H1c in a similar way, considering the maximum homology with H1b and H1d. Each N-terminal serine residue is acetylated, too. H1a consists of 222 amino acid residues and has a molecular weight of 22,178 in its unmodified form; the H1c consists of 220 residues and has a molecular weight of 22,218 in that form. The human spleen H1 sequences varied to about the same extent in the N-terminal 40 and C-terminal 110 residues. However, the sequences of the about 70 internal residues are well conserved between the variants. The extent of differences among the human H1 variants is similar to, or rather smaller than, those among the mammalian somatic H1 species. The implications of these differences in the sequence for H1 function are discussed from the evolutionary viewpoint.  相似文献   

15.
Antiserum directed against bovine heart mitochondrial NADH dehydrogenase has been used to screen a rat liver cDNA expression library in lambda gt11. The insert cDNA of a positive clone was found to represent the 24-kDa subunit of NADH dehydrogenase by epitope selection using nitrocellulose filter containing the expressed proteins. The amino acid sequence deduced from the nucleotide sequence of the cloned cDNA indicated that the 24-kDa subunit is produced as a precursor with an amino-terminal extension, and that its mature form consists of 217 amino acid residues with a molecular weight of 23,933.  相似文献   

16.
The amino acid sequence of the beta-chain of the principal haemoglobin from A. trapezia has been determined. The sequence was deduced from the sequences of tryptic peptides, which were fractionated using highperformance liquid chromatography and peptide mapping. Additional sequence data, particularly for the large tryptic peptides, was obtained from enzyme digests of both cyanogen bromide fragments and large citraconyltryptic peptides. The beta-chain has 151 residues which is longer than all the other sequenced haemoglobin chains except the alpha-chain of A. trapezia, which is 153 residues in length. The residues corresponding to those normally in the D helix are absent in this beta-chain. The additional residues are contributed by an extension of the N-terminal region, which was also found to be acetylated. Comparison of the beta-chain amino acid sequence with that of the alpha-chain of A. trapezia, the dimeric chain of A. trapezia, and the dimeric chain of A. broughtonii showed 53% identity in each case. In the E and F helices, the homology is particularly noticeable. There is 100% homology in the F helix of all four chains. The dimeric globin of A. trapezia also shows 100% homology with the beta-chain in the E helix, while the alpha-chain shows 75%. If the tertiary structure of the alpha- and beta-chains of A. trapezia haemoglobin is the same as that of horse haemoglobin, then there are many changes in the alpha 1 and beta 2 contact site residues.  相似文献   

17.
The complete primary structure of the human type IV collagen alpha 2(IV) chain has been determined by nucleotide sequencing of cDNA clones. The overlapping cDNA clones cover 6,257 base pairs with a 5'-untranslated region of 283 base pairs, the 5,136-base pair open reading frame, and the 3'-untranslated region of 838 base pairs. The predicted amino acid sequence demonstrates that the complete translation product consists of 1,712 residues corresponding in molecular weight to 167,560. The translated polypeptide has a signal peptide of 36 amino acids, an amino-terminal noncollagenous part of 21 residues, a 1,428-residue collagenous domain with 23 interruptions, and a carboxyl-terminal noncollagenous (NC) domain of 227 residues. The calculated molecular mass of the mature human alpha 2(IV) chain is 163,774 Da.  相似文献   

18.
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   

19.
The nucleotide sequence coding for sex-limited protein (Slp), the testosterone-regulated isotype of the fourth component of mouse complement (C4), has been determined from cloned genomic DNA and cDNA fragments. The complete deduced amino acid sequence for the single chain precursor protein of Slp (pro-Slp) consists of 1716 residues. The mature beta, alpha, and gamma subunits contain 654, 763, and 291 amino acids, respectively. One potential carbohydrate attachment site is predicted from the beta-chain, five for the alpha-chain, and none for the gamma-chain. From the comparison with the mouse C4 sequences, an extensive overall sequence homology, 96.0% in nucleotides and 94.2% in amino acids, is observed. Only one deletion/insertion event is recognized between C4 and Slp sequences: three residues near the Cls cleavage site are deleted from Slp. The distribution of cysteine residues is completely conserved between pro-Slp and pro-C4.  相似文献   

20.
The luxE gene of bioluminescent bacteria encodes the acyl-protein synthetase component of the fatty acid reductase complex. The complex is responsible for converting tetradecanoic acid to the aldehyde which serves as a substrate in the luciferase-catalyzed reaction. The nucleotide sequence of the luxE gene of Vibrio harveyi was determined and the amino acid sequence of the acyl-protein synthetase deduced. The protein consists of 378 amino acid residues and has a molecular weight of 42,965 daltons. Alignment of the V. harveyi enzyme with the V. fischeri acyl-protein synthetase showed 62% identity.  相似文献   

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