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W J Moore

Publications and source records attributed to W J Moore.

At least 37 records · Page 2Linked to original sources
PubMed1986

NMR studies of myelin basic protein. XIII. Assignment of histidine residues in rabbit, bovine and porcine proteins.

Myelin basic protein from three species (rabbit, cow and pig) and peptides from enzymatic digests or cleavage of the proteins have been examined in aqueous solutions by proton nuclear magnetic resonance (NMR) at 400 MHz. The epsilon 1-CH and delta 2-CH resonances of all the histidine residues in the three proteins have been assigned and the pK values have been measured. The heterogeneity of chemical shifts among these resonances can be variously ascribed to persistent localized secondary structures and to effects arising from charged side-chains, particularly those of aspartic acid residues, and from side-chains of aromatic moieties.

Animals↗
PubMed1985

Conformation of two antigenic regions in myelin basic protein.

Four different regions of myelin basic protein from various species have been reported to be the antigenic sites (epitopes) for seven monoclonal antibodies evoked in rats or mice by guinea pig or monkey basic protein. The structures of the epitopes located in the amino-terminal region and in the eight-residue sequence including S-133, were examined by proton n. m. r at 400 MHz in aqueous solutions of peptides obtained by enzymatic cleavage of the rabbit protein. The data suggest conformational similarities between the two regions.

Amino Acid Sequence↗
PubMed1985

N.m.r. studies of myelin basic protein. Conformation of a peptide that is an antigenic determinant for B-cell reactivity.

The peptide Gly-Arg-Ala-Ser-Asp-Tyr-Lys-Ser, derived from myelin basic protein (MBP), is part of an epitope to monoclonal antibodies to human MBP. Its conformation has been studied in aqueous solution by high-resolution one- and two-dimensional 1H and 13C n.m.r. Two-dimensional correlated spectroscopy, pH titrations and one-dimensional spin-decoupling techniques were employed to assign the spectra observed from both nuclei. Amide proton temperature coefficients, coupling constants, 13C spin-lattice relaxation times and nuclear-Overhauser-effect data provide evidence that the solution conformations of the octapeptide include a type-II beta-turn with a hydrogen bond between the CO group of Arg2 and the NH group of Asp5. The results are discussed in view of a possible conformation of the antibody receptor site.

Antibodies, Monoclonal↗
PubMed1985

Proton-n.m.r. study of interaction of myelin basic protein with a monoclonal antibody.

Proton n.m.r. at 400 MHz has been applied to study the interactions of bovine or porcine myelin basic protein (b- or p-MBP) with a monoclonal antibody to human (h-) MBP. The antibody, an IgG immunoglobulin that contains a sequential epitopic region, cross-reacts with b-MBP but not with p-MBP, the presumed epitope being identical in h- and b-MBP. N.m.r. spectra were recorded from the Fab fragment of the antibody and for mixtures of Fab and MBP at various molar ratios. The n.m.r. spectrum of MBP in the mixture consists mostly of well resolved peaks against a broad background due to the Fab. With b-MBP, but not p-MBP, specific interactions are observed at the residue tyrosine-135, which is part of the epitopic sequence. Other interactions occur between the Fab and both b- and p-MBP at residues distant from the epitopic region. Standard radioassay techniques were employed to calculate the binding constants of both basic proteins with the immunoglobulin. The binding constant, Kb, for IgG to column-immobilized b-MBP at 298K is (0.95 +/- 0.07) X 10(7) dm3/mol. The value of Kb decreases with the ionic strength of the medium, suggesting a coulombic interaction between antigen and antibody. N.m.r. spectra were also measured for mixtures of the Fab fragment and peptides containing the epitopic site, with results in agreement with those for the whole protein.

Antibodies, Monoclonal↗
PubMed1985

Infant feeding and subsequent risk of atopic eczema.

An attempted controlled trial of exclusively breast fed neonates with atopic parents, to assess the effectiveness of breast feeding in preventing atopic allergy, was not successfully achieved. Analysis of the data as an observational study, however, provided evidence that breast feeding offers some protection against eczema in genetically vulnerable infants. Feeds of soya preparations were associated with eczema as often as cows' milk based feeds.

Age Factors↗
PubMed1984

Interaction of myelin basic protein with micelles of dodecylphosphocholine.

Interactions of myelin basic protein (MBP) and peptides derived from it with micelles of dodecylphosphocholine (DPC) and perdeuterated DPC have been studied by proton nuclear magnetic resonance (NMR) at 400 MHz and by circular dichroism (CD). When MBP binds to DPC micelles, it acquires about 18% alpha-helicity. The CD spectra of various peptides derived by cleavage of MBP indicate that a major alpha-helical region occurs in residues 85-99 just before the sequence of three prolyl residues 100-102. From line broadenings by fatty acid spin-labels in the micelles and from changes in chemical shifts, the NMR data identify specific residues in MBP that participate in lipid binding. One such sequence is an alpha-helical region from residues 85 to 95, and others occur around methionine-21 and between residues 117 and 135. The different effects of C5, C12, and C16 spin-labels suggest that some segments of the protein may penetrate beyond the dipolar interfacial region of the micelles into the hydrophobic interior, but no part of the protein is protected by the micelles against rapid exchange of its amide groups with the aqueous environment. Even at a lipid to protein molar ratio of 200/1, most NMR resonances from side chains of amino acid residues are not appreciably broadened, suggesting that much of the polypeptide remains highly mobile.

Animals↗
PubMed1983

NMR studies of myelin basic protein. IX. Complete assignments of the tyrosine residues by proton NMR of proteins from six species.

All the proton resonances from the tyrosine residues are assigned in 400 MHz NMR spectra in aqueous solution of myelin basic proteins from human, cow, pig, rabbit, rat (small protein) and chicken. Assignments are based on species comparisons, spectra of enzymatic cleavage products of the basic protein, pH titrations, broadening effects of Gd(III), and nuclear Overhauser effects. The mobile extended polypeptide chain structure of the protein facilitates the detection of interactions between nearest neighbors. Evidence is found for reverse turns in the structure in regions of encephalitogenic determinants.

Animals↗
PubMed1983

NMR studies of myelin basic protein. X. Conformation of a determinant encephalitogenic in the rabbit.

Residues 67 to 75 in myelin basic protein from several species comprise the sequence Thr-His-Tyr-Gly-Ser-Leu-Pro-Gln-Lys that acts as an encephalitogenic determinant in the rabbit. Proton magnetic resonance spectra of human, bovine and porcine proteins display nuclear Overhauser effects between the delta-CH of Tyr-69 and the delta-CH3 of Leu-72, which indicate reverse-turn conformations about the Gly-Ser residues. This effect occurs also in physiological saline solution at pH 6.0 but in dimethylsulfoxide solution the nuclear Overhauser effect disappears. Circular dichroism indicates that the protein when bound to ganglioside micelles acquires 30-40% alpha-helical conformation, but the reverse turn still persists in the sequence of the rabbit encephalitogen. These results suggest that the encephalitogenic region of the protein remains at the aqueous interface of the micelles.

Amino Acid Sequence↗
PubMed1983

Cell kinetics of growth cartilage in stumpy: a new chondrodystrophic mutant in the mouse.

The proximal growth plates of the tibiae in normal and stumpy mice aged 10-41 days were studied. Autoradiographic studies using tritiated thymidine enabled the size of the proliferating cell population and the labelling indices of the growth plates to be determined. Hypertrophic cell heights were also measured. From these data the overall growth rates for the proximal growth plate of the tibia in normal and stumpy mice were calculated. It was found that the major factor responsible for the reduced growth rate in stumpy up to 21 days was the small hypertrophic cell height, while cell proliferation zone size and labelling indices were of minor importance. Histological observations also revealed a lack of organised endochondral ossification, which worsens with age.

Aging↗
PubMed1982

Trypan blue teratogenesis in the rat: further observations in vitro.

Explanted 9 1/2- and 10 1/2-day rat conceptuses were cultured for 24 or 48 hours and 24 hours respectively in immediately centrifuged, heat-inactivated rat serum to which trypan blue was added at concentration of 150 micrograms/ml or 300 micrograms/ml or 450 micrograms/ml. The embryos were assessed for normal growth and differentiation using the following criteria: heart beat, vitelline circulation, fusion of the allantois with the chorion, normal turning, normally closed neural tube, presence of optic vesicles, presence of forelimb buds, tail, somites, somite number, yolk sac diameter, crown-rump length, and protein content. The results indicated that trypan blue is more teratogenic when 9 1/2-day conceptuses are cultured for the first 24 hours, and that its teratogenicity decreases after 10 1/2 days. Morphological abnormalities produced included neural tube defects, turning defects, and tail defects, the tail abnormalities being manifest as fluid-filled blebs. Ten and one-half-day conceptuses cultured for 24 hours in treated serum produced predominantly tail defects. The conceptuses were cultured at 11 days, when the embryo lies completely within the yolk sac. Culture of such conceptuses in serum containing 450 micrograms/ml trypan blue produced mainly tail defects. Injection of 0.5 microliters of 0.5% dye solution into the yolk sac cavity also produced tail abnormalities; sham treatment, or the injection of sterile water or a nonteratogenic dye, azo blue, did not affect embryonic development.

Animals↗
PubMed1981

Conformations of P2 protein of peripheral nerve myelin by nuclear magnetic resonance spectroscopy.

High-resolution 1H NMR spectra of P2 protein from bovine peripheral nerve myelin indicate that the protein contains a high degree of tertiary structure in aqueous solution. Denaturation of the protein in urea solutions is a multi-step process. Binding of lysophosphatidylcholine micelles to the protein causes a conformational change and a broadening of NMR peaks from side chains of aromatic amino acid and methionine residues, with much less effect on upfield methyl resonances.

Animals↗