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)

Parameters of rotational relaxation of pepsin conjugated in neutral and slightly alkaline solutions with a fluorescent label 1-dimethylaminonaphthalene-5-sulphonyl chloride (DNS-Cl) are measured by a fluorescence polarization method. It is shown that the globule of pepsin denatured and loose at lakaline pH values converts into a compact form after transfer to acidic solution. The compactness of this new form is close to that of native inhibited pepsin. A new globule is distinguished from the native by the absence of segmental flexibility. Conjugated with a DNS at pH less than or equal to 7.0 pepsin relaxes in solution as catalytically active dansylated aminopepsin (DNS-3-aminotyrosine pepsin). Evidence is presented that these conjugates are also characterized by segmental flexibility.
Mol Biol (Mosk)
PMID:[The fluorescence of pepsin conjugates with DNS-chloride]. 0 44

By modifying four tyrosine residues in pepsin a derivative (aminopepsin) is obtained which is capable to conjugate with a fluorescent label DNS-Cl without loss of the catalytic activity. Rotational relaxation times of native pepsin and dansylated aminopepsin (DAP) are measured by a fluoresence polarization method. The values obtained are shown to be lower than those calculated for arigid pepsin globule. Possible sources of the obtained difference are discussed. A reversible or covalent blocking of pepsin or DAP active centres by specific inhibitors leads to an increase in rotational relaxation time values for these proteins reaching the magnitude which is very close to that calculated for a model of rigid pepsin. Brownian relaxation of pepsin and DAP reduced by beta-mercaptoethanol and of pepsinogen and some fragments of pepsine macromolecule in aqueous solutions is invigated as well. The results are intepreted as representing an intramolecular mobility or segmental flexibility of pepsin and DAP. With the use of the obtained and X-ray data a segmental model of dynamic pepsin structure is suggested. On the basis of this model some conclusions are drawn concerning a localization of a polypeptide which is split off from the N-terminus of pepsinogen during its activation. A possible role of segmental flexibility in the catalytic action of pepsin is considered.
Mol Biol (Mosk)
PMID:[Intramolecular mobility of pepsin]. 78 36

Human leukocyte interferon-A1 (IFN-alpha A) structure in solution was investigated by fluorescence polarization, circular dichroism and scanning microcalorimetry techniques. Using gel-filtration it was established that at neutral pH values and at concentration not exceeding 0.3 mg/ml IFN-alpha A has a dimeric configuration in solution. At pH below 5, IFN-alpha A exists as a monomer. Using circular dichroism technique the IFN-alpha A molecule was shown to preserve a native structure upon decreasing pH to 3.5. The rotational correlation time of IFN-alpha A molecule in dimeric and monomeric form was measured using fluorescence of DNS, conjugated with the protein, and fluorescence of tryptophan residues. Our data indicate that the shape of IFN-alpha A molecule may be approximated by the rigid ellipsoid of revolution with the axis ratio = 4:1. The intramolecular melting of IFN-alpha A was studied by scanning microcalorimetry and circular dichroism in the acidic pH range. Thermodynamic analysis reveals two independent cooperative transitions. These transitions can be explained by assuming that the IFN-alpha A molecule consists of two structural domains.
Mol Biol (Mosk)
PMID:[Study of the structural properties of recombinant leukocyte interferon A by means of fluorescence polarization, circular dichroism, and differential microcalorimetry]. 179

In 7 of 37 patients with cutaneous melanoma, mutations in the N-ras gene were found. The primary tumors of these seven patients were exclusively localized on body sites continuously exposed to sunlight. Moreover, the ras mutations were all at or near dipyrimidine sites known to be targets of UV damage. Two primary tumors were biclonal with respect to ras mutation. An active role for UV irradiation in induction of the mutations is suggested.
Mol Cell Biol 1989 Jul
PMID:N-ras mutations in human cutaneous melanoma from sun-exposed body sites. 267 80

A high affinity (Ka = 2-3 x 10(10) M-1) murine monoclonal anti-fluorescein IgM antibody (18-2-3) exhibiting low temp. insolubility in the absence of bound ligand has served as a model to study cryoprecipitation. Insolubility of 18-2-3 at low temp. (4 degrees C) had been shown to be reversible at higher temp. and in the presence of fluorescyl ligand, indicating antigen binding site involvement. The primary objectives were to isolate and identify structural component(s) responsible for insolubility at low temp. Procedures developed for production and isolation of the monomeric subunit (IgMs) involved thiol reduction and gel filtration separation in the presence of the zwitterionic detergent, CHAPS. Fab and (Fc)5 fragments generated by papain digestion were purified sequentially by gel filtration (Sephadex G-200) and affinity chromatography (fluorescein-Sepharose). A protocol for covalent labeling of Fab fragments with the fluorescent chromophore 2,5 DNS-Cl was developed in order to measure steady-state fluorescence polarization. In kinetic and equilibrium cryoprecipitation assays, nonliganded 18-2-3 IgM and IgMs demonstrated insolubility. Bound fluorescyl ligand, increased ionic strength (0.5 M NaCl) or basic pH (greater than 8.0) abrogated cryoprecipitation. Isolated Fab or (Fc)5 fragments did not exhibit low temp. insolubility. Decreased cryoprecipitation occurred when (Fc)5 fragments were added to nonliganded 18-2-3 IgM. Fluorescence polarization of 2,5 DNS Fab 18-2-3 fragments indicated lack of Fab-Fab aggregation. Results suggested that electrostatic interactions involving 18-2-3 antibody combining sites with interactive sites in the Fc region of homologous IgM were responsible for the phenomenon of cryoprecipitation.
Mol Immunol 1988 Dec
PMID:Cryoprecipitation properties of a high-affinity monoclonal IgM anti-fluorescyl antibody. 323 15

Protein MAT is a homogeneous human IgM (lambda) cryoprecipitating cold agglutinin wherein the Fabmu and Fcmu5 fragment interaction is facilitated at low temps. Thermal dependence of the association of 2,5 DNS labeled Fab MAT with unlabeled Fcmu5 MAT was examined by fluorescence depolarization. The association data, treated by the method of van't Hoff, showed a nonlinear increase in binding with decreased temp, suggestive of certain dynamic changes in the system. Temperature effects on the rotational diffusion of five different 1,5 DNS labeled Fabmu fragments (including two derived from cryoglobulins) were also examined by fluorescence polarization. The linear nature of the Perrin plots derived from the data failed to reveal temp-induced hydrodynamic changes in any of the Fabmu fragments studied. Involvement of carbohydrates in the low-temp self-association of protein MAT was established by the finding that glycopeptides isolated from another IgM molecule (BAZ) could inhibit (as judged by depolarization of fluorescence) the interaction of 2,5 DNS labeled Fabmu MAT and unlabeled Fcmu5 BAZ fragments. These findings indicate that, although cryoprecipitation of protein MAT seemingly involves an antigen-antibody-like reaction between a site on the Fab region and carbohydrate moieties on the Fcmu5 region, no direct evidence for a low-temp-induced conformational change in the Fab region was obtained.
Mol Immunol 1984 Jan
PMID:The molecular mechanism of cryoimmunoglobulin precipitation--II. Thermodynamic basis for self-association as determined by fluorescence polarization. 670 59

CAP-dependent promoters can be divided into classes based on the position of the DNA site for CAP. In class I CAP-dependent promoters, the DNA site for CAP is located upstream of the DNA site for polymerase; the DNA site for CAP can be located at various distances from the transcription start point, provided that the DNS site for CAP and the DNA site for RNA polymerase are on the same face of the DNA helix. In class II CAP-dependent promoters, the DNA site for CAP overlaps the DNA site for RNA polymerase, replacing the -35 determinants for binding of RNA polymerase. In previous work, we have shown that a surface loop consisting of amino acid residues 152 to 166 of CAP is essential for transcription activation at the best-characterized class I CAP-dependent promoter, the lac promoter, and we proposed that this surface loop makes direct protein-protein contact with RNA polymerase in the ternary complex of lac promoter, CAP, and RNA polymerase. Here, we show that the surface loop consisting of amino acid residues 152 to 166 is essential for transcription activation at other class I CAP-dependent promoters and at a class II CAP-dependent promoter. We show further that the effects of alanine substitutions of residues 152 to 166 are qualitatively identical at the lac promoter and other class I CAP-dependent promoters, but are different at a class II CAP-dependent promoter. We propose that the surface loop consisting of residues 152 to 166 makes identical molecular interactions in transcription activation at all class I CAP-dependent promoters, irrespective of distance between the DNA site for CAP and the transcription start point, but makes a different set of molecular interactions in transcription activation at class II CAP-dependent promoters.
J Mol Biol 1994 Nov 04
PMID:Characterization of the activating region of Escherichia coli catabolite gene activator protein (CAP). II. Role at Class I and class II CAP-dependent promoters. 796 85

The presence of high concentrations of membrane-bound carboxypeptidase M in human, baboon, dog, and rat lung was established by employing a variety of techniques. The activity of the enzyme in the membrane-enriched fractions of human, baboon, dog, and rat lung, measured with fluorescent dansyl substrate (DNS-Ala-Arg), was 198, 261, 484, and 153 nmol/h/mg protein, respectively. This activity in the lung was much higher than that found in the heart, liver, or kidney. The enzyme, optimally active around neutral pH, was completely inhibited by 10 microM 2-mercaptomethyl-3-guanidinoethylthiopropanoic acid and was activated by 1 mM CoCl2 to 170%. Antibody to human carboxypeptidase M immunoprecipitated the solubilized carboxypeptidase from human (98%), baboon (81%), and dog (88%) lung membrane fractions. Carboxypeptidase M is attached to lung membranes by a phosphatidylinositol glycan anchor; thus, it is released with bacterial phospholipase C. Membrane fractions from cultured human pulmonary arterial endothelial cells also contained high carboxypeptidase M activity (254 nmol/h/mg protein). A Northern blot of poly(A)+ RNA from various human tissues showed the presence of a high level of carboxypeptidase M mRNA in human lung and placenta. Finally, immunohistochemistry, employing purified antibody to the enzyme, revealed in fluorescent light microscopy that carboxypeptidase M is present in alveolar type I pneumocytes and in macrophages in apparently lower concentration. In contrast, type II alveolar epithelial cells gave negative results. Because carboxypeptidase M cleaves a variety of active peptides (e.g., bradykinin, anaphylatoxins), it may protect the alveolar surface from the effects of these peptides. In addition, carboxypeptidase M could be a marker enzyme for type I cells.
Am J Respir Cell Mol Biol 1993 Aug
PMID:High concentration of carboxypeptidase M in lungs: presence of the enzyme in alveolar type I cells. 833 89

Among the large family of fatty acid binding proteins, the liver L-FABP is unique in that it not only binds fatty acids but also interacts with sterols to enhance sterol transfer between membranes. Nevertheless, the mechanism whereby L-FABP potentiates intermembrane sterol transfer is unknown. Both fluorescence and dialysis data indicate L-FABP mediated sterol transfer between L-cell fibroblast plasma membranes occurs by a direct membrane effect: First, dansylated-L-FABP (DNS-L-FABP) is bound to L-cell fibroblast plasma membranes as indicated by increased DNS-L-FABP steady state polarization and phase resolved limiting anisotropy. Second, coumarin-L-FABP (CPM-L-FABP) fluorescence lifetimes were significantly increased upon interaction with plasma membranes. Third, dialysis studies with 3H-cholesterol loaded plasma membranes showed that L-FABP added to the donor compartment of the dialysis cell stimulated 3H-cholesterol transfer whether or not the dialysis membrane was permeable to L-FABP. However, L-FABP mediated intermembrane sterol transfer did require a sterol binding site on L-FABP. Chemically blocking the ligand binding site also inhibited L-FABP activity in intermembrane sterol transfer. Finally, L-FABP did not act either as an aqueous carrier or in membrane fusion. The fact that L-FABP interacted with plasma membrane vesicles and required a sterol binding site was consistent with a mode of action whereby L-FABP binds to the membrane prior to releasing sterol from the bilayer.
Mol Cell Biochem 1995 Nov 08
PMID:Liver fatty acid binding protein enhances sterol transfer by membrane interaction. 860 11

Epidermal gene delivery techniques are being developed as an experimental approach to understanding the pathogenesis of skin disorders and for developing therapeutic strategies for the treatment of disease. This technology is being evaluated in many clinical trials in the treatment of disorders such as cutaneous melanoma and skin wounding, with 20% of all gene therapy protocols being applied in the field of dermatology. This review focuses on recent advances in the development of gene transfer technology to the epidermis, describing the diseases that may be amenable to treatment by use of these strategies. We will discuss the advantages and limitations of the currently used techniques and the future prospects for gene therapy via the epidermis.
Hum Mol Genet 1997
PMID:Gene delivery to the epidermis. 930 Jun 69


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