Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Poly (A+)-mRNA obtained from human term placenta using guanidine HCl and oligo (dT) cellulose chromatography was translated in a wheat germ cell-free system. SDS-polyacrylamide gel electrophoresis analysis of the translation products revealed the presence of several polypeptides with molecular weights ranging from 10 KD to 70 KD. A single protein band representing around 1% of the total radioactive proteins synthesized in the presence of 2.5 micrograms of mRNA was isolated by immunoprecipitation, using specific antiserum against either the native 'Pregnancy-specific beta 1-glycoprotein' or a reduced and carboxymethylated derivative. The molecular weight of 31-2 KD of this translation product corresponding to the nonprocessed precursor could account for the 43 KD value assigned to the protein purified form human pregnant serum.
Mol Biol Rep 1987
PMID:Identification and molecular weight of SP1 synthesized from mRNA of human placenta in a wheat germ cell-free system. 288 15

A large heparan sulfate proteoglycan of low buoyant density (p = 1.32 to 1.40 g/cm3 in 6 M-guanidine.HCl) was extracted from a tumor basement membrane with denaturing solvents and purified by chromatography and CsCl gradient centrifugation. Chemical, immunological, physical and electron microscopical analyses have demonstrated a high degree of purity and have allowed us to propose a structural model for this proteoglycan. It is composed of an 80 nm long protein core formed from a single polypeptide chain (Mr about 500,000) with intrachain disulfide bonds. This core is folded into a row of six globular domains of variable size as shown by electron microscopy after rotary shadowing and negative staining. A multidomain structure was confirmed by protease digestion experiments that allowed the isolation of a single heparan sulfate-containing peptide segment representing less than 5% of the total mass of the protein core. Electron microscopy has visualized generally three heparan sulfate chains in each molecule close to each other at one pole of the protein core. The molecular mass and length (100 to 170 nm) of the heparan sulfate chains were found to vary consistently between different preparations. The mass per length ratio (350 nm-1) indicated an extended conformation for the heparan sulfate side-chains. These structural features are distinctly different from those of the high density proteoglycan, suggesting that both forms of basement membrane heparan sulfate proteoglycan are genetically distinct and not derived from a common precursor.
J Mol Biol 1987 Sep 20
PMID:Structure of low density heparan sulfate proteoglycan isolated from a mouse tumor basement membrane. 296 Aug 21

The statistical segment length of duplex DNA was determined in phage T4 ligase (poly(deoxyribonucleotide): poly(deoxyribonucleotide) ligase (AMP forming), EC 6.5.1.1) buffer (50 mM-Tris . HCl (pH 7.8), 20 mM-dithiothreitol, 10 mM-MgCl2, 1 mM-ATP) at 12 degrees C to be 1030(+/- 116) A. This result was obtained by electron microscopic examination of the molecular distributions generated by T4 ligase-mediated joining of EcoRI-cleaved pBR322 DNA. This value of the statistical segment length was utilized in an extension of the Jacobson-Stockmayer theory on the probability of intramolecular cyclization in order to optimize DNA joining reactions that are of great utility in recombinant DNA experiments. Five cloning systems were analyzed: circular plasmid vectors that had been linearized with one or two restriction endonucleases, circular plasmids that had been tailed with deoxyhomopolymers before joining, lambda-type cloning vectors and cosmids. The results are tabulated for convenient use in molecular cloning experiments.
J Mol Biol 1985 Jan 20
PMID:Analysis and optimization of recombinant DNA joining reactions. 298 33

The specificity of a frequently-occurring precipitin response to soluble antigens from cell-walls and culture filtrates of A. viscosus ATCC 19246 was examined. After precipitation with isopropanol (50-75% v/v), antigen fractions of different charge and molecular weight were isolated by ion exchange and gel filtration. When heated in mineral acid or alkali above 0.15 M, each of the purified antigens lost precipitating activity, but now inhibited the precipitin reaction between serum and exogenous unheated antigen. The inhibitor was isolated over Biogel P30 and characterized as a peptide fragment (mol. wt about 2 kd) containing approximately 50 moles of ornithine and 6-12 moles, respectively, of aspartate, serine, threonine, glutamate, glycine, alanine and histidine per 100 moles amino acids. The inhibitor was totally destroyed by heating for 1.0 hr in 2.0 M HCl. Variability in the number of fragments and differences in the non-antigenic portions probably accounted for the complexity of the antigens. Ornithine, putrescine, N-acetyl putrescine and various sugars had little or no effect on the precipitin reaction with intact antigen at high concentrations (200 mM), whereas the fragment inhibited completely at 0.4 mM. This indicates that neither ornithine nor its side-chain amides are exclusively recognized by antibody. However, ornithine may be part of a larger sequence and/or important in forming the configuration recognized by the human antibodies.
Mol Immunol 1986 Mar
PMID:Analysis of the specificity of natural human antibody reactive to Actinomyces. 308 11

Dimeric human secretory IgA was completely reduced with mercaptoethanol and alkylated with [14C]iodoacetamide. The component polypeptide chains were separated by high performance gel filtration in 5 M guanidine HCl into two fractions: one containing secretory component (SC) + heavy (H) chains; and the second containing light (L) + J chains. L and J chains were subsequently separated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate (SDS) or in alkaline urea. Calculations of the J chain stoichiometry in the dimeric secretory IgA (S-IgA) molecule were based on: the measurement of the ratio of radioactivities of SC + H chain and L + J chain-fractions or L chain- and J chain-fractions; the known stoichiometry of SC, H and L chains; and the known number of half-cystine residues in the component polypeptide chains of S-IgA molecule. The data demonstrated that one molecule of dimeric S-IgA contains approx. one J chain.
Mol Immunol 1986 May
PMID:The stoichiometry of J chain in human secretory dimeric IgA. 309 31

Reductive methylation of botulinum neurotoxin (NT) serotypes A and B at various ratios of protein to reagent modified up to 75% of the lysine residues. Amino acid analysis of the modified proteins (HCl hydrolysed) confirmed selective modifications of lysine. The derivative N,N-dimethyl lysine was more abundant than monomethyl lysine; trimethyl lysine was not detected. Distribution of modified lysine residues among the heavy and light chains (Mr approximately 100,000 and approximately 50,000, respectively) of the dichain type A NT (Mr approximately 150,000) was approximately proportional to the lysine contents of the two subunit chains of the NT. Toxicity (mouse lethality) and serological reactivity (polyclonal antibody) of serotype A NT were not (or insignificantly) damaged following methylation of up to 72 lysine residues. Modification of 3 additional residues caused precipitous loss in toxicity. Toxicity of serotype B NT, unlike type A, appeared more sensitive to lysine modification. The large number of lysine residues that can be methylated without damaging toxicity of type A NT can be exploited to a) radiolabel the dichain protein exclusively in one chain keeping the other chain unlabelled, b) restrict the number of tryptic cleavage sites of the NT, and c) tag the protein with various markers or reactive ligands.
Mol Cell Biochem 1988 Sep
PMID:Reductive methylation of lysine residues of botulinum neurotoxin types A and B. 314 88

The human (h) POMC gene sequence predicts a 30 amino acid joining peptide (JP) separating the N-terminal fragment [POMC(1-76) or hNT] and ACTH within their common precursor. We used an anti-serum directed against the amidated COOH-terminal end of mouse JP to develop a RIA for the predicted hJP molecule. Immunoreactive JP was detected in tissue extracts from human normal pituitary, ACTH-secreting pituitary- and nonpituitary tumors, and in plasma from patients with ACTH hypersecretory syndromes. Its molar concentration was of the same order of magnitude as, and correlated with, that of the other POMC peptides. Gel exclusion chromatography in 1% formic acid and 6 M guanidine-HCl revealed a predominant immunoreactive material with an apparent mol wt of ca. 6000. After reduction with dithiothreitol this material was recovered in an elution volume identical to that of purified hJP and corresponding to a mol wt of ca. 3000. These data show that POMC processing generates a COOH terminally amidated hJP predominantly secreted as a homodimer, probably through disulfide bonding between the single Cys9 residue of two molecules.
Mol Endocrinol 1988 Nov
PMID:Human joining peptide: a proopiomelanocortin product secreted as a homodimer. 322 77

The initial rate of formation of insoluble immune complexes from rabbit IgG and ovalbumin was approximately 12 times that for formation of F(ab')2-ovalbumin complexes. At low IgG concns, in the range 0.7-2.7 nM, the formation of insoluble immune complexes was characterised by a lag phase, especially for complexes formed in low antigen excess, compared to antibody excess. Guanidine HCl (at concns up to 0.5 M) and urea (at concns up to 1 M) decreased the initial rates of formation of IgG immune complexes more than F(ab')2 immune complexes. Pre-formed IgG immune complexes were solubilised at lower guanidine HCl concns than were F(ab')2 immune complexes. C1q enhanced the initial rate of formation of IgG immune complexes at C1q:IgG ratios up to 1:1. Higher C1q concns decreased the initial rate of formation of the complexes. Urea (1 M) blocked the C1q mediated enhancement of immune complex formation.
Mol Immunol 1988 Dec
PMID:The role of Fc:Fc interactions in insoluble immune complex formation and complement activation. 323 16

Groups of CBA mice were administered [35S] methionine (1 mCi/mouse). Non-histone proteins, H1 and H1(0) histones and nucleosomal core histones were isolated from different issues by selective extractions. The measurements of radioactivity of individual bands and autoradiography of dry gels were used to identify methionine-containing and methionine-free histone variants. H1A and H1B histone variants extracted with 5% perchloric acid were methionine-free. However, minor sub-fractions of these histones which are more tightly bound to DNA (and which can be extracted only with 0.25 N HCl) contained [35S] methionine and did show a higher specific activity than methionine-containing nucleosomal hitones. Cyanogen Bromide reaction which destroys non-histone proteins and methionine-containing nucleosomal histones removes radioactivity but does not alter the position of methionine-containing H1 minor bands. This indicates that the radioactive methionine occupies only the N-terminus of the H1 molecules. It is suggested that this methionine is an uncleaved initiator methionine. The presence of these methionine-containing minor H1 subfractions varies in different tissues.
Mol Biol Rep
PMID:Identification of minor tightly bound H1 histone subfractions which fail to cleave their initiator methionine. 325 50

The activating effect of peptides sequentially related to the Ile 16-Val17-Gly18 N-terminus of bovine beta-trypsin (namely Ile-Val-Gly, Ile-Val, Ile-Leu, Ile-Ala, Val-Val, Leu-Val, and Val-Leu) on the thermodynamic parameters for the binding of the porcine pancreatic secretory trypsin inhibitor (Kazal inhibitor) and benzamidine to bovine trypsinogen was investigated at pH 5.5 (Bis tris-HCl buffer, I = 0.1 M) and T = 21 +/- 0.5 degrees C. Thermodynamic parameters for Kazal inhibitor and benzamidine association to the binary peptide/zymogen adducts are more favorable than those observed for ligand binding to the proenzyme alone, although never as much as those reported for the formation of bovine beta-trypsin/Kazal inhibitor and bovine beta-trypsin/benzamidine adducts. Analogously, the affinity of activating peptides for the binary proenzyme/Kazal inhibitor and binary proenzyme/benzamidine complexes is higher than that observed for peptide binding to free bovine trypsinogen. Differences in affinity for ligand binding to free bovine trypsinogen, to its binary adducts and to bovine beta-trypsin suggest the presence of different activation levels of the proenzyme, none of which structurally coincide with that achieved in bovine beta-trypsin. The existence of different discrete states suggests that the zymogen-to-active enzyme transition should not be considered as a two-state process but as a multistep event.
J Mol Recognit 1988 Jun
PMID:Zymogen activation: effect of peptides sequentially related to the bovine beta-trypsin N-terminus on Kazal inhibitor and benzamidine binding to bovine trypsinogen. 327 24


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