Showing papers on "Peptide sequence published in 1982"

Single amino acid substitution altering antigen-binding specificity

Abstract: S107, a phosphocholine-binding myeloma protein, has been cloned in soft agar, and an antigen-binding variant has been isolated and characterized. The variant does not bind phosphocholine attached to carrier or as free hapten in solution but does retain antigenic determinants (idiotypes) of the parent. Chain recombination experiments suggest that the defect in binding is entirely in the heavy chain. Amino acid sequence analysis showed a single substitution--glutamic acid to alanine at position 35--in the first hypervariable or complementarity-determining region. In terms of the three-dimensional model of the phosphocholine-binding site, glutamic acid-35 provides a hydrogen bond to tyrosine-94 of the light chain that appears to be critical for stability of this portion of the binding site. The removal of this bond and the presence of the smaller alanine side chain is thus consistent with the loss in binding activity. These results suggest that small numbers of substitutions in antibodies, such as those presumably introduced by somatic mutation, may in some situations be effective in altering antigen-binding specificity.

Neuropeptide Y: complete amino acid sequence of the brain peptide.

Abstract: The amino acid sequence of neuropeptide Y, a 36-residue peptide recently isolated from porcine brain, has been determined by using high performance liquid chromatography for separation of its tryptic and chymotryptic fragments and subsequent sequence analysis of the isolated fragments by an improved dansyl Edman subtractive technique. The amino acid sequence of neuropeptide Y has been found to be: Tyr-Pro-Ser-Lys-Pro-Asp-Asn-Pro-Gly-Glu-Asp-Ala-Pro-Ala-Glu-Asp-Leu-Ala-Arg-Tyr -Tyr-Ser-Ala-Leu-Arg-His-Tyr-Ile-Asn-Leu-Ile-Thr-Arg-Gln-Arg-Tyr-NH2. Neuropeptide Y has a high degree of sequence homology with peptide YY (70%), the newly isolated porcine intestinal peptide, and pancreatic polypeptide (50%). It is therefore proposed that neuropeptide Y, peptide YY, and pancreatic polypeptide are members of a newly recognized peptide family.

Four small Drosophila heat shock proteins are related to each other and to mammalian alpha-crystallin

Abstract: The primary base sequence of the protein coding regions of the four small heat shock genes of Drosophila melanogaster present at cytological locus 67B has been determined. A single open reading frame large enough to encode a small heat shock protein is found for each gene. The molecular weights of the predicted proteins are in good agreement with experimentally determined values obtained from gel electrophoresis. The predicted amino acid sequences of the four small heat shock genes show striking homologies over approximately 50% of their lengths. This region of extensive homology extends from about amino acid 85 to amino acid 195 out of a total of approximately 200 amino acids. Comparison of the predicted sequence with the known sequences of other proteins revealed a remarkable similarity between this region of homology and the corresponding region of mammalian alpha-crystallin. The possible functional significance of this structural similarity is discussed.

Cloning and sequence analysis of cDNA for porcine beta-neo-endorphin/dynorphin precursor

Abstract: The primary structure of a precursor protein that contains beta-neo-endorphin, dynorphin and a third leucine-enkephalin sequence with a carboxyl extension has been deduced from the nucleotide sequence of cloned DNA complementary to the porcine hypothalamic mRNA encoding it. The three peptides are each bounded by Lys-Arg. This precursor protein, like adrenal preproenkephalin and the corticotropin/beta-lipotropin precursor, comprises multiple repetitive units and a cysteine-containing amino-terminal sequence preceded by a signal peptide.

Nucleotide sequence of tobacco mosaic virus RNA

Abstract: Oligonucleotide primers have been used to generate a cDNA library covering the entire tobacco mosaic virus (TMV) RNA sequence. Analysis of these clones has enabled us to complete the viral RNA sequence and to study its variability within a viral population. The positive strand coding sequence starts 69 nucleotides from the 5' end with a reading frame for a protein of Mr 125,941 and terminates with UAG. Readthrough of this terminator would give rise to a protein of Mr 183,253. Overlapping the terminal five codons of this readthrough reading frame is a second reading frame coding for a protein of Mr 29,987. This gene terminates two nucleotides before the initiator codon of the coat protein gene. Potential signal sequences responsible for the capping and synthesis of the coat protein and Mr 29,987 protein mRNAs have been identified. Similar sequences within these reading frames may be used in the expression of sets of proteins that share COOH-terminal sequences.

Primary structure of the human Met- and Leu-enkephalin precursor and its mRNA

Abstract: The nucleotide sequence of a complete cDNA copy of enkephalin precursor mRNA from human phaeochromocytoma is reported The corresponding amino acid sequence shows that the precursor is 267 amino acids long and contains six interspersed Met-enkephalin sequences and one Leu-enkephalin sequence Five of the seven enkephalins are flanked on both sides by pairs of basic amino acid residues The precursors does not contain the sequences of the opioid peptides, dynorphin, alpha-neo-endorphin or beta-endorphin

Isolation and characterization of peptide YY (PYY), a candidate gut hormone that inhibits pancreatic exocrine secretion

Abstract: A new candidate hormone--designated peptide YY (PYY)--has been isolated from extracts of porcine upper intestinal tissue by using a novel chemical assay method. This peptide has been detected in the extracts by the presence of its unusual COOH-terminal tyrosine amide structure. The peptide consists of a linear chain of 36 amino acids and its complete amino acid sequence is: Tyr-Pro-Ala-Lys-Pro-Glu-Ala-Pro-Gly-Glu-Asp-Ala-Ser-Pro-Glu-Glu-Leu-Ser-Arg-Tyr -Tyr-Ala-Ser-Leu-Arg-His-Tyr-Leu-Asn-Leu-Val-Thr-Arg-Gln-Arg-Tyr-NH2. This peptide has a distinct sequence homology to the pancreatic polypeptide. It is therefore proposed that PYY and the pancreatic polypeptide together form a new peptide family. PYY has been found to strongly inhibit both secretin- and cholecystokinin-stimulated pancreatic secretion in the anesthetized cat.

Mechanism of C-terminal amide formation by pituitary enzymes

Abstract: The amino acid sequences of peptide hormones that terminate in an α-amide group seem usually to be followed by glycine in the sequence of their precursor molecules. Thus it has long been known that the sequence of α-melanotropin, which terminates in Lys-Pro-Val-CONH2 (ref. 1), occurs adjacent to glycine in the sequence of corticotropin2 and more recently it has been shown that the peptide hormone mellitin, which terminates in glutamine amide3, is synthesized as a prohormone that terminates in glutaminyl-glycine4. A similar relationship is suggested by comparison of the primary structures of adipokinetic hormone5 and red pigment-concentrating hormone6. These observations indicate that biosynthesis of the C-terminal amide may involve the action of a specific enzyme which has a requirement for C-terminal glycine. We present here direct evidence that porcine pituitary contains an enzyme with the ability to convert peptides that terminate in glycine to the corresponding des-glycine peptide amide. We have investigated the substrate specificity of the enzyme and with the aid of isotopic labelling have demonstrated that its mechanism of action involves dehydrogenation and hydrolysis of the glycine-containing substrate.

Structure and possible catalytic residues of Taka-amylase A

Abstract: A complete molecular model of Taka-amylase A consisting of 478 amino acid residues was built with the aid of amino acid sequence data. Some typical structural features of the molecule are described. A model fitting of an amylose chain in the catalytic site of the enzyme showed a possible productive binding mode between substrate and enzyme. On the basis of the difference Fourier analysis and the model fitting study, glutamic acid (Glu230) and aspartic acid (Asp297), which are located at the bottom of the cleft, were concluded to be the catalytic residues, serving as the general acid and base, respectively.

Structure of the human immune interferon gene

Abstract: Sequence determination of cloned cDNAs and genes of the three classes of interferon (IFN-alpha, -beta and -gamma) has revealed more than a dozen members of the human IFN-alpha gene family and a single gene for IFN-beta. These genes are found on chromosome 9 and contain no introns. We recently reported that the 146-amino acid sequence of mature IFN-gamma deduced from the nucleotide sequence of a cloned cDNA was quite unrelated to those of the other IFNs, and that the gene for IFN-gamma contains at least one intron. We now describe the isolation, characterization and DNA sequence of the human IFN-gamma gene. It contains three introns, a repetitive DNA element, and is not highly polymorphic. All our evidence to date and the present data suggest that this is the only gene for IFN-gamma and that the resolution of IFN-gamma into two components is probably the result of post-translational processing of the protein.

Isolation and characterization of a cDNA coding for human factor IX

Abstract: A cDNA library prepared from human liver has been screened for factor IX (Christmas factor), a clotting factor that participates in the middle phase of blood coagulation. The library was screened with a single-stranded DNA prepared from enriched mRNA for baboon factor IX and a synthetic oligonucleotide mixture. A plasmid was identified that contained a cDNA insert of 1,466 base pairs coding for human factor IX. The insert is flanked by G-C tails of 11 and 18 base pairs at the 5' and 3' ends, respectively. It also included 138 base pairs that code for an amino-terminal leader sequence, 1,248 base pairs that code for the mature protein, a stop codon, and 48 base pairs of noncoding sequence at the 3' end. The leader sequence contains 46 amino acid residues, and it is proposed that this sequence includes both a signal sequence and a pro sequence for the mature protein that circulates in plasma. The 1,248 base pairs code for a polypeptide chain composed of 416 amino acids. The amino-terminal region for this protein contains 12 glutamic acid residues that are converted to gamma-carboxyglutamic acid in the mature protein. These glutamic acid residues are coded for by both GAA and GAG. The arginyl peptide bonds that are cleaved in the conversion of human factor IX to factor IXa by factor XIa were identified as Arg145-Ala146 and Arg180-Val181. The cleavage of these two internal peptide bonds results in the formation of an activation peptide (35 amino acids) and factor IXa, a serine protease composed of a light chain (145 amino acids) and a heavy chain (236 amino acids), and these two chains are held together by a disulfide bond(s). The active site residues including histidine, aspartate, and serine are located in the heavy chain at positions 221, 270, and 366, respectively. These amino acids are homologous with His57, Asp102, and Ser195 in the active site of chymotrypsin. Two potential carbohydrate binding sites (Asn-X-Thr) were identified in the activation peptide, and these were located at Asn157 and Asn167. The homology in the amino acid sequence between human and bovine factor IX was found to be 83%.

Homology among DNA-binding proteins suggests use of a conserved super-secondary structure.

Abstract: The amino acid sequences of the repressor and cro proteins of phages lambda, 434 and P22 are homologous, especially in a region in which repressor and lambda cro have a similar alpha-helix-turn-alpha-helix secondary structure Model-building studies indicate that this structure is important in DNA binding, and we suggest it may be a common feature of many DNa-binding proteins

The amino acid sequence of chicken muscle desmin provides a common structural model for intermediate filament proteins.

Abstract: The complete amino acid sequence of muscle desmin reported here is the first for an intermediate filament protein Alignment with partial data available for vimentin, glial fibrillary acid protein, neurofilament 68 K, two wool alpha-keratins, and a recently described DNA clone covering 90% of an epidermal keratin shows that all seven proteins have extensive homologies and therefore form a complex multigene family, the intermediate filament proteins The hard alpha-keratins of wool appear to be a special subset of epithelial keratins The sequence information reveals, as the dominant structural principle, a rod-like middle domain arising from several alpha-helical segments able to form interchain coiled-coil elements The proposed helices are separated by short spacers, which like the two terminal domains seem built from non-alpha-helical material Attention is drawn to the sometimes very striking sequence homologies along the rod and the high sequence variability in the terminal domains Finally, chemical cross-linking experiments performed on the isolated desmin rod show that intermediate filament structure seems not to be based on triple-stranded coiled-coils as currently thought, but rather reflects protofilament units built as a dimer of normal interchain double-stranded coiled-coils

Conservation of high efficiency promoter sequences in Saccharomyces cerevisiae.

Abstract: The position of the yeast phosphoglycerate kinase (PGK) gene has been mapped on a 2.95kb Hind III fragment. We have determined the nucleotide sequence of the 5' flanking region and compared this sequence with those from 16 other yeast genes. PGK, like all other yeast genes has an adenine residue at position -3. It has two possible TATA boxes at positions -114 and -152 and a CAAT box at -129. In addition we have defined a structure at position -63 to -39 that is common to all yeast genes that encode an abundant RNA. This structure is a CT-rich block followed, about 10 nucleotides later, by the sequence CAAG.

Nucleotide sequence of the gene for the M(r) 32,000 thylakoid membrane protein from Spinacia oleracea and Nicotiana debneyi predicts a totally conserved primary translation product of M(r) 38,950.

Abstract: The gene for the so-called Mr 32,000 rapidly labeled photosystem II thylakoid membrane protein (here designated psbA) of spinach (Spinacia oleracea) chloroplasts is located on the chloroplast DNA in the large single-copy region immediately adjacent to one of the inverted repeat sequences. In this paper we show that the size of the mRNA for this protein is ≈ 1.25 kilobases and that the direction of transcription is towards the inverted repeat unit. The nucleotide sequence of the gene and its flanking regions is presented. The only large open reading frame in the sequence codes for a protein of Mr 38,950. The nucleotide sequence of psbA from Nicotiana debneyi also has been determined, and comparison of the sequences from the two species shows them to be highly conserved (>95% homology) throughout the entire reading frame. Conservation of the amino acid sequence is absolute, there being no changes in a total of 353 residues. This leads us to conclude that the primary translation product of psbA must be a protein of Mr 38,950. The protein is characterized by the complete absence of lysine residues and is relatively rich in hydrophobic amino acids, which tend to be clustered. Transcription of spinach psbA starts about 86 base pairs before the first ATG codon. Immediately upstream from this point there is a sequence typical of that found in E. coli promoters. An almost identical sequence occurs in the equivalent region of N. debneyi DNA.

Location and characterization of the antigenic portion of the FMDV immunizing protein

Abstract: Purified foot-and-mouth disease virus (FMDV) to type O1K was treated with several endopeptidases of differing specificity. The immunizing protein VPThr was cleaved into two detectable fragments by all enzymes except for glutamic acid-specific Staphylococcus aureus V8 protease. The longest fragments were generated by mouse submaxillary gland protease and the shortest by trypsin treatment of the intact virion. Several fragments, including the peptides resulting from the cyanogen bromide (CNBr) cleavage of the isolated protein VPThr were characterized in terms of their molecular weights N- and C-terminal amino acids, and ability to induce virus-specific antibodies. The order of the fragments along the protein was determined, and then located on the amino acid sequence of the protein. Two enzyme-sensitive areas of the protein were found on the surface of the virion: between sequence positions 138 and 154 and between portion 200 and the C terminus. Peptides containing these sections were able to induce neutralizing antibodies against the homologous FMDV. When the virus was treated with trypsin or with chymotrypsin, several amino acids between the detectable fragments were lost and the infectivity of the virus was reduced. The infectivity was retained, however, when the enzyme treatment resulted in cleavage of protein with no loss of amino acids or only the cutting away of the C-terminal section. These results suggest that the property of cell attachment is restricted to small regions of the surface of the virus particle.

Antibodies against a preselected peptide recognize and neutralize foot and mouth disease virus.

Abstract: A major antibody combining site on foot and mouth disease virus (FMDV) serotype O1K has been identified in a predicted surface helix of viral protein 1 (VP1) between amino acid residues 144 and 159. A hexadecapeptide covering this sequence elicits high titers of antibodies that specifically recognize and neutralize FMDV. The high quality of the immune response is attributed to a particularly stable conformation of the antigenic amino acid sequence, which is most likely an alpha-helix.

n-Tetradecanoyl is the NH2-terminal blocking group of the catalytic subunit of cyclic AMP-dependent protein kinase from bovine cardiac muscle.

Abstract: The unusual NH2-terminal blocking group of the catalytic subunit of bovine cardiac muscle cyclic AMP-dependent protein was found to be amide-linked n-tetradecanoic acid by gas chromatographic-, direct chemical ionization-, and fast atom bombardment-mass spectrometry. In addition, fast atom bombardment mass spectrometry revealed the presence of an additional alanine which had been overlooked when the original sequence was determined. The corrected and completed NH2-terminal sequence of the 350-amino acid catalytic subunit is CH3(CH2)12CONH-Gly-Asn-Ala-Ala-Ala-Ala-Lys.

Isolation and structural organization of the human preproenkephalin gene

Abstract: The primary structure of porcine preproenkephalin B has been elucidated by cloning and sequencing cDNA: it contains neoendorphin, dynorphin and leumorphin (containing rimorphin as its amino-terminus). These opioid peptides, each having a leucine-enkephalin structure, act on the kappa-receptor. We have now cloned a human genomic DNA segment containing the preproenkephalin B gene. The structural organization of this gene resembles those of the genes encoding the other opioid peptide precursors, that is, preproenkephalin A and the corticotropin-beta-lipotropin precursor (ACTH-beta-LPH precursor). The primary structure of human preproenkephalin B has been deduced from the gene sequence. The amino acid sequence homology observed between preproenkephalin B and preproenkephalin A, together with the similarity between their gene organizations, suggests that the two genes have been generated from a common ancestor by gene duplication.

Sequence and structure of yeast phosphoglycerate kinase.

Abstract: The structure of yeast phosphoglycerate kinase has been determined with data obtained from amino acid sequence, nucleotide sequence, and X-ray crystallographic studies. The substrate binding sites, as deduced from electron density maps, are compatible with known substrate specificity and the stereochemical requirements for the enzymic reaction. A carboxyl-imidazole interaction appears to be involved in controlling the transition between the open and closed forms of the enzyme.

Redesigning enzyme structure by site-directed mutagenesis: tyrosyl tRNA synthetase and ATP binding

Abstract: We describe here a general method for systematically replacing amino acids in an enzyme. This allows analysis of their molecular roles in substrate binding or catalysis and could eventually lead to the engineering of new enzymatic activities. The gene encoding the enzyme is first cloned into a vector from which the enzyme is expressed and is then mutated in vitro to change a particular nucleotide and hence the amino acid sequence of the enzyme. We have cloned the gene for the tyrosyl tRNA synthetase of Bacillus stearothermophilus into a vector derived from the single-stranded bacteriophage M13 to facilitate mutagenesis with mismatched synthetic oligodeoxynucleotide primers. From the recombinant M13 clone we have obtained high levels of the enzyme (∼50% of soluble protein) expressed in the Escherichia coli host and have converted cysteine (Cys35) at the enzyme's active site to serine. This leads to a reduction in enzymatic activity that is largely attributable to a lower Km for ATP.

Human gamma-trace, a basic microprotein: amino acid sequence and presence in the adenohypophysis

Abstract: The amino acid sequence of human gamma-trace, a basic microprotein without known function, was determined by automated Edman degradations of the carboxymethylated polypeptide chain and of fragments obtained by cyanogen bromide treatment and tryptic digestion after blocking of lysine residues. The single polypeptide chain contained 120 residues, and the calculated Mr was 13,260. A proline residue at position 3 was partly hydroxylated. The presence of gamma-trace in a significant proportion of the cells in the anterior lobe of simian and human pituitary glands was demonstrated by immunohistochemical procedures with a rabbit antiserum against human gamma-trace. The tissue localization and amino acid sequence of gamma-trace indicated that this protein is connected with the peptidergic gastroenteropancreatic neuroendocrine system.

Nucleotide sequence and the encoded amino acids of human serum albumin mRNA

Abstract: The complete nucleotide sequence of human serum albumin mRNA has been determined from recombinant cDNA clones and from a primer-extended cDNA synthesis on the mRNA template. The sequence is composed of 2078 nucleotides, starting upstream from a potential ribosome binding site in the 5' untranslated region. It contains all the translated codons and extends into the poly(A) at the 3' terminus. Part of the translated sequence codes for a hydrophobic prepeptide, Met-Lys-Trp-Val-Thr-Phe-Ile-Ser-Leu-Leu-Phe-Leu-Phe-Ser-Ser-Ala-Tyr-Ser, followed by a basic propeptide, Arg-Gly-Val-Phe-Arg-Arg. These signal peptides are absent from mature normal serum albumin and, so far, have not been identified in their nascent state in humans. A remaining 1755 nucleotides of the translated mRNA sequence code for 585 amino acids, which are in agreement, with few exceptions, with the published amino acid sequence for human serum albumin. The mRNA sequence verifies and refines the repeating homology in the triple-domain structure of the serum albumin molecule.

Complete amino acid sequence of an HLA-DR antigen-like beta chain as predicted from the nucleotide sequence: similarities with immunoglobulins and HLA-A, -B, and -C antigens.

Abstract: The complete nucleotide sequence of an HLA-DR antigen-like beta-chain cDNA clone was determined. The 1,080 base pairs include the complete coding region and most of the untranslated portion. The predicted amino acid sequence has 229 residues. The beta chain contains two immunoglobulin-like disulfide loops and a 21-amino acid residue membrane-integrated segment. Ten amino acid residues reside on the cytoplasmic side of the plasma membrane. The single asparagine-linked carbohydrate moiety is attached to asparagine-19. The NH2-terminal 91 residues of the beta chain are homologous to the corresponding region of HLA-A, -B, and -C antigen heavy chains. Residues 92-192 of the beta chain display statistically significant homology to members of the immunoglobulin family, beta 2-microglobulin, and the immunoglobulin-like domain of HLA-A, -B, and -C antigen heavy chains. These data establish that the major histocompatibility antigens of class I and class II type and the constant regions of immunoglobulins are evolutionarily related.

Herpes simplex virus type-1 glycoprotein D gene: nucleotide sequence and expression in Escherichia coli.

Abstract: The protein coding region of the herpes simplex virus type-1 glycoprotein D (gD) gene was mapped, and the nucleotide sequence was determined. The predicted amino acid sequence of the gD polypeptide was found to contain a number of features in common with other virus glycoproteins. Insertion of this protein coding region into a bacterial expressor plasmid enabled synthesis in Escherichia coli of an immunoreactive gD-related polypeptide. The potential of this system for preparation of a type-common herpes simplex virus vaccine is discussed.