Myoglobins
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Myoglobins: the link between discoloration and lipid oxidation in muscle and meat
Aerobic metabolism changes rapidly to glycolysis post-mortem resulting in a pH-decrease during the transformation of muscle in to meat affecting ligand binding and redox potential of the heme iron in myoglobin, the meat pigment. The "inorganic chemistry" of meat involves (i) redox-cycling between iron(II), iron(III), and iron(IV)/protein radicals; (ii) ligan
Química Nova. Publicado em: 2006-12
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2. Estudos estruturais das mioglobinas de "Aplysia Brasiliana" e "Dermochelis Coriacea " por técnicas ópticas e ressonância paramagnética eletrônica / Structural studies of Aplysia Brasiliana and Demochelis Coriacea myoglobins by optical techniques and electron paramagnetic resonance
Neste trabalho são estudadas as mioglobínas de Aplysía Brasiliana (MbApB) e da tartaruga marinha "Dermoche lis Coriacea" (MbT) focalizando a transição ácida alcalina (TAA), a interação com metais de transição e mudanças conformacionais induzidas - termicamente com objetivo de observar diferenças estruturais destas mioglobinas. A TAA da MbApB poss
Publicado em: 1984
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3. Bacterial glutamate racemase has high sequence similarity with myoglobins and forms an equimolar inactive complex with hemin.
Glutamate racemase (EC 5.1.1.3), an enzyme of microbial origin, shows significant sequence homology with mammalian myoglobins, in particular in the regions corresponding to the E and F helices, which constitute the heme binding pocket of myoglobins. Glutamate racemase binds tightly an equimolar amount of hemin, leading to loss of racemase activity. Although
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4. A possible immunodominant epitope recognized by murine T lymphocytes immune to different myoglobins.
We find that a single region on the surface of different species of myoglobin appears to be immunodominant for T lymphocytes, even though the residues in that region vary sufficiently that the T cells immune to one myoglobin do not crossreact with other myoglobins bearing substitutions at that site. Immunization of B10.S mice with sperm whale myoglobin elici
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5. Metastable CO binding sites in the photoproduct of a novel cooperative dimeric hemoglobin.
The infrared absorption spectrum of the CO-photoproduct from Scapharca inaequivalvis hemoglobin (Hbl) at 10 K yields only a single line in the "B" state region at 2132 cm-1. This is the same frequency as the B1 line observed in photodissociated vertebrate HbCO and MbCO. No evidence was found for the B2 line detected in vertebrate hemoglobins and myoglobin in
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6. Structure-dynamics-function relationships in Asian elephant (Elephas maximus) myoglobin. An optical spectroscopy and flash photolysis study on functionally important motions.
In this work we report the thermal behavior (10-300 K) of the Soret band lineshape of deoxy and carbonmonoxy derivatives of Asian elephant (Elephas maximus) and horse myoglobins together with their carbon monoxide recombination kinetics after flash photolysis; the results are compared to analogous data relative to sperm whale myoglobin. The Soret band profil
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7. NUCLEAR MAGNETIC RESONANCES OF RECONSTITUTED MYOGLOBINS
In proton nuclear magnetic resonance spectra of paramagnetic heme proteins, the resonances of the heme groups are shifted away from those of the many hundred protons of the polypeptide chains by interactions with the unpaired electrons and are therefore well resolved at 220 Mc. This paper describes experiments from which these resolved resonances are assigne
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8. How frequent are correlated changes in families of protein sequences?
A loss-of-function point mutation in a protein is often rescued by an additional mutation that compensates for the original physical change. According to one hypothesis, such compensation would be most effective in maintaining a structural motif if the two mutated residues were spatial neighbors. If this hypothesis were correct, one would expect that many su
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9. Theoretical Study of the Electrostatic and Steric Effects on the Spectroscopic Characteristics of the Metal-Ligand Unit of Heme Proteins. 2. C-O Vibrational Frequencies, 17O Isotropic Chemical Shifts, and Nuclear Quadrupole Coupling Constants
The quantum chemical calculations, vibronic theory of activation, and London-Pople approach are used to study the dependence of the C-O vibrational frequency, 17O isotropic chemical shift, and nuclear quadrupole coupling constant on the distortion of the porphyrin ring and geometry of the CO coordination, changes in the iron-carbon and iron-imidazole distanc
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10. The distal residue-CO interaction in carbonmonoxy myoglobins: a molecular dynamics study of two distal histidine tautomers.
Four independent 90 ps molecular dynamics simulations of sperm-whale wild-type carbonmonoxy myoglobin (MbCO) have been calculated using a new AMBER force field for the haem prosthetic group. Two trajectories have the distal 64N delta nitrogen protonated, and two have the 64N epsilon nitrogen protonated; all water molecules within 16 A of the carbonyl O are i
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11. Formation of two hydrogen bonds from the globin to the heme-linked oxygen molecule in Ascaris hemoglobin.
We have tried to find out why Ascaris hemoglobin has such an exceptionally high oxygen affinity (P50 approximately 0.004 mmHg; 1 mmHg = 133 Pa). Following Kloek et al., we have synthesized the N-terminal globin domain of Ascaris hemoglobin in Escherichia coli [Kloek, A. P., Yang, J., Mathews, F. S. & Goldberg, D. (1993) J. Biol. Chem. 268, 17669-17671]. Like