Showing papers on "Myoglobin published in 1979"
TL;DR: The heme irons between hemoglobin and myoglobin and physical and chemical Criteria for Quaternary Structure and effects of quaternary structure on thermal spin equilibria are described.
Abstract: PERSPECTIVES AND SUMMARY 328 INTRODUCTION 330 STEREOCHEMISTRY OF IRON PORPHYRINS AND RELATED COMPOUNDS 332 Coordination of the Iron Atom 332 Interaction between Structure and Spin State in Iron Chelates 338 The Iron-Oxygen Bond 340 STEREOCHEMISTRY OF HEMOGLOBINS ".. 343 Monomeric and Dimeric Hemoglobins 343 Common tertiary structure ".. 343 Surroundings and structure of the heme in myoglobin.. ...... ........ ....... 344 Surroundings and structure of the heme in erythrocruorin 346 Tetrameric Hemoglobins 348 Changes in quaternary structure "... 349 Changes in tertiary structure 349 Significance of structural changes for ligand binding 353 Structural differences at the heme irons between hemoglobin and myoglobin 356 INTERACTIONS BETWEEN THE HEME AND THE GLOBIN 356 Physical and Chemical Criteria for Quaternary Structure 357 Methods of Changing Liganded Derivatives to the T Structure 359 Effects 0/ Changes in Quaternary Structure on the Heme 360 Deoxyhemoglobin 360 Liganded fe7roU!1 henwglobins ". 361 Ligandedferric henwglobins ,. 363 Effect of quaternary structure on thermal spin equilibria ........ ......... ........ ....... 366
620 citations
TL;DR: The present calculations provide a useful first step in the analysis of the effect of the globin matrix on the binding process, and make use of a simplified model of the ligand-myoglobin system.
400 citations
TL;DR: In this paper, the resonance Raman spectrum (RRS) of deoxy myoglobin (Mb) in the lowest frequency region was investigated, in which the Fe-N, (His) stretching frequency provided an important insight into molecular mechanism of biolo&al reactions catalyzed by the enzyme.
186 citations
TL;DR: Beef heart muscle has been found to contain an enzyme which will rapidly and directly reduce metmyoglobin in vitro, which is NADH-dependent and requires the presence of ferrocyanide ion for in vitro assay.
175 citations
155 citations
TL;DR: Mechanisms for the resonance enhancement of the main low-frequency bands are discussed on the basis of the excitation profiles and of the dispersion curves for depolarization ratios obtained for fluorometmyoglobin and hydroxymetmyoglobin.
Abstract: The low-frequency regions (150--700 cm-1) of resonance Raman (RR) spectra of various complexes of oxidized and reduced horse heart myoglobin were examined by use of 441.6-nm excitation. In this frequency range, RR spectra show 10 bands common to all myoglobin derivatives (numbered here for convenience from I to X). Relative intensities of bands IV, V, and X constitute good indicators of the doming state of the heme and, consequently, of the spin state of the iron atom. An additional band is present for several complexes (fluorometmyoglobin, hydroxymetmyoglobin, azidometmyoglobin, and oxymyoglobin). Isotopic substitutions on the exogenous ligands and of the iron atom (56Fe leads to 54Fe) allow us to assign these additional lines to the stretching vibrations of the Fe-sixth ligand bond. Similarly, bands II are assigned to stretching vibrations of the Fe-N-(pyrrole) bonds. An assignment of bands VI to stretching vibrations of the Fe-Nepsilon(proximal histidine) bonds is also proposed. Mechanisms for the resonance enhancement of the main low-frequency bands are discussed on the basis of the excitation profiles and of the dispersion curves for depolarization ratios obtained for fluorometmyoglobin and hydroxymetmyoglobin.
109 citations
TL;DR: Using an immunoperoxidase method, myoglobin is localized in the cytoplasm of normal and neoplastic human skeletal muscle and is discussed in connection with myoglobin as a tissue-specific marker for skeletal muscle neoplasms.
Abstract: Using an immunoperoxidase method, myoglobin is localized in the cytoplasm of normal and neoplastic human skeletal muscle. The staining intensity is variable in individual cells. This can be explained by the variable concentration of myoglobin in the different fiber types of normal muscle or
105 citations
92 citations
TL;DR: The nuclear modulation pattern in the envelope of electron spin echoes for various low spin paramagnetic heme proteins, using the three-pulse-stimulated echo method, is observed and the heme of low spin ferric cytochrome P-450 is coordinated to a nitrogenous ligand, probably imidazole.
86 citations
TL;DR: The data are consistent with a model in which protonation of the distal histidine permits protein-free heme FeCO geometry in leghemoglobin-- CO complexes but not in myoglobin-- or hemoglobin--CO complexes, and the heme pockets of leghemoglobins appear to be more flexible than the he me pockets of myoglobin and hemoglobin.
Abstract: The effects of pH upon infrared spectra [CO stretching frequency (vco) region] and visible spectra of the CO complexes of soybean leghemoglobins a, c1, and c2, sperm whale myoglobin, and human hemoglobin A are reported. The vco for leghemoglobin--CO complexes was 1947.5 cm-1 at neutral pH. At acid pH myoglobin-- and hemoglobin--CO complexes developed vco bands at 1966--1968 cm-1, whereas leghemoglobin--CO complexes developed vco bands at approximately 1957 cm-1. All pKapp co values determined by pH-dependent variation of vco fell in the range 4.0--4.6. The pKapp co values determined from visible spectra were consistent with vco-determined values except for that of myoglobin--CO (visible pKapp co = 5.8). The pKapp co values in the 4.0--4.6 range appear to be pK values of the distal histidines, while the visible pKapp co of myoglobin--CO appears to be the pK of a group other than the distal and proximal histidines. The data are consistent with a model in which protonation of the distal histidine permits protein-free heme FeCO geometry in leghemoglobin--CO complexes but not in myoglobin-- or hemoglobin--CO complexes. Thus the heme pockets of leghemoglobins appear to be more flexible than the heme pockets of myoglobin and hemoglobin. The effects of pH upon visible spectra of the O2 complexes of soybean leghemoglobins a, c1, and c2, sperm whale myoglobin, and human hemoglobin A also are reported. pKapp o2 values of approximately 5.5 (leghemoglobins) and 4.4 (hemoglobin) are probably the pK values of the distal histidines. Comparisons of pKapp o2 values with pKapp co values indicate a more flexible heme pocket in leghemoglobins than in hemoglobin. The O2 complex of leghemoglobin c2 differed significantly from the O2 complexes of leghemoglobins a and c1 in visible spectra and titration behavior. These differences might be associated with the small structural differences in the region between the E and F helixes of leghemoglobins.
78 citations
TL;DR: In immunoadsorbent titration studies, the sum of the amounts of antibodies bound in the plateau by the adsorbents of the five sites accounted quantitatively for the entire (100%) antibody response to sperm-whale myoglobin.
TL;DR: The subunit-exchange chromatography method is applicable to cardiac, smooth, or skeletal muscle from mammals, reptiles, birds, and teleost fish, but failed with the one amphibian and the one shark tested.
TL;DR: This different ratio for CO provides further evidence for steric interaction of the bound CO with the protein based on a consideration of the preferred nonlinear geometry of Fe-NO and Fe-O2 and the linear geometry ofFe-CO.
Abstract: The Soret absorption maxima and extinction coefficients of the CO and NO complexes of horse myoglobin and (NMeIm)protoheme (NMeIm = 1-methylimidazole) have been determined. The partition coefficient N, equal to the ratio P1/2 (CO)/P1/2(NO), has been determined spectrophotometrically for horse myoglobin and (NMeIm)protoheme. P1/2-(NO) values calculated from the partition coefficients are 5.7 x 10(7) mmHg for (NMeIm)protheme and 1.1 x 10(6) mmHg for horse myoglobin. The ratio of P1/2(NO) values for protein and model is 1.9 which is similar to a value of 1.6 reported for the ratio of P1/2(O2) values. These values may be compared to a ratio of 15 for CO binding to protein and model complexes. This different ratio for CO provides further evidence for steric interaction of the bound CO with the protein based on a consideration of the preferred nonlinear geometry of Fe-NO and Fe-O2 and the linear geometry of Fe-CO.
TL;DR: Single-proton, exchangeable resonances have been detected in the high spin ferric hemoproteins, met-aquo myoglobin and horseradish peroxidase, which can be assigned to the proximal histidyl imidazole by virtue of their very large hyperfine shifts, indicating a buried heme pocket.
TL;DR: Determination of myoglobin in serum by sensitive and specific method might be of clinical value in the diagnosis of diseases involving muscle tissues and presence of other myoglobin binding substances in serum seemed unlikely.
Abstract: Two solid-phase radioimmunoassays have been developed for the detection of myoglobin in serum and urine. The sensitivity of the methods is 0.1 and 0.5 microgram/l, respectively, with a coefficient of variation of the respective method of 7-8%. The mean serum concentration of myoglobin in ninety-nine healthy blood donors was 44.3 microgram/l +/- 18.0 microgram/l (SD) with a significant difference (P less than 0.001) between men (50.6 +/- 19.8) and women (35.7 +/- 10.4). Serum myoglobin was positively correlated to age (P less than 0.05), body weight (P less than 0.02), serum creatine kinase (P less than 0.001), and serum creatinine (P less than 0.001) to galactose elimination rate. Serum myoglobin levels were not influenced by exhaustive short time dynamic exercise. The mean urinary excretion of myoglobin in twenty-four healthy students was 1.2 microgram/24 h (range 0.1-4 microgram/24 h). Myoglobin excretion was correlated to excretion of beta 2-microglobulin (P less than 0.02) but not to serum levels of myoglobin. No indications of circulating antibodies to myoglobin were obtained when assaying sixty-seven rheumatoid arthritis and thirteen myastenia gravis sera. Presence of other myoglobin binding substances in serum, which would interfere with the assays also seemed unlikely. Determination of myoglobin in serum by sensitive and specific method might be of clinical value in the diagnosis of diseases involving muscle tissues.
TL;DR: The potential application of low-temperature radiolysis method to produce oneelectron-addition compounds of the oxygen-hemoprotein complexes in glassy matrices for spectroscopic analysis is demonstrated and the data show the differences in the pathway of oneElectron reduction of oxyperoxidase and oxymyoglobin, which can be correlated with basic functional properties of the hemoproteins.
TL;DR: The observed effect of the addition of myoglobin or hemoglobin α-chains on the minimum gelling concentration of sickle cell hemoglobin is smaller than predicted, and it is suggested that this difference may arise from self-association of the added species.
TL;DR: The binding of various linear and branched chain alkylisocyanides to soybean leghemoglobin has been studied with respect to association and dissociation kinetics and the results compared with those obtained in parallel on sperm whale and horse heart myoglobins; the linear ligands used cover a greater distribution of chain lengths than hitherto used.
TL;DR: The circular dichroism of the porphyrin transitions suggests that the packing of the amino acid side chains around the p Morphyrin is different than that in the native metmyoglobin.
Abstract: Copper(II) protoporphyrin IX has been introduced into apomyoglobin, and its utility as a reporter group of the heme environment has been examined. The Soret and visible absorption bands and electron spin resonance spectrum show that the Cu(II) is five coordinate, probably through coordination to the F-8 proximal histidine. The resonance Raman spectrum does not indicate any appreciable distortion from the solution conformation of copper(II) protoporphyrin IX dimethyl ester in CS2. The ultraviolet circular dichroism shows no alteration of the helical content of the globin from that of metmyoglobin. The circular dichroism of the porphyrin transitions suggests that the packing of the amino acid side chains around the porphyrin is different than that in the native metmyoglobin.
TL;DR: In this paper, the effects of ionizing radiation on beef pigments were studied by determining the absorption spectra of myoglobin solutions and the reflectance spectrum of radiation-sterilized beef slices.
Abstract: Effects of ionizing radiation on beef pigments were studied by determining the absorption spectra of myoglobin solutions and the reflectance spectra of radiation-sterilized beef slices. Bovine and ovine oxymyoglobin (MbO2) and met(ferri)myoglobin (metMb) were extracted, purified, and treated with gamma radiation. Increasing dose and temperature of gamma radiation produced increasing shifts in characteristic peaks and progressive decreases in the Soret bands of these pigments. The total color difference (▵E), computed from tri-stimulus values of reflectance spectra of radiation-sterilized beef, showed similar dependence of color on radiation dose and temperature. Re-irradiation of beef allowed to brown in air caused the unstable red pigment to re-form. The presence of oxygen in the container during radiation-sterilization reduced the red color formation. The results show that ionizing radiation reduces the heme iron of the brown pigment of cooked meat (globin myohemichromogen) to an unstable red pigment (globin myohemochromogen), which, upon exposure to air, reverts to the original ferric (brown) pigment.
TL;DR: The kinetics of methemoglobin reduction by Fe(EDTA) 2− have been studied and found to follow a second order rate law with k = 29.0 M −1 s −1 and values range over ten orders of magnitude with heme ⪢ myoglobin > hemoglobin.
TL;DR: Serum myoglobin levels were measured in normal, hyperthyroid, and hypothyroid subjects by RIA and there was a significant inverse correlation between serum T4 or T3 levels and Mb levels in these subjects.
Abstract: Serum myoglobin (Mb) levels were measured in normal, hyperthyroid, and hypothyroid subjects by RIA. Serum Mb levels were significantly higher (P < 0.001) in untreated hypothyroid patients and significantly lower (P < 0.01) in untreated hyperthyroid patients than in normal subjects. There was a significant inverse correlation (P < 0.001) between serum T4 or T3 levels and Mb levels in these subjects. Serum Mb levels were normalized after correction of the abnormal thyroid states.
TL;DR: The results suggest that detection of serum myoglobin by enzyme‐immunoassay may be a valuable test in the early diagnosis of acute myocardial infarction.
TL;DR: Investigation of the effect of temperature on the stability of the Fe(II) myoglobin-ligand complexes indicates that more than one bound states exists in dissociation of the ligand molecule from the ferrous heme iron of the reduced azide and imidazole derivatives.
TL;DR: Compared with myoglobins from species previously studied, there are many more differences in amino acid sequences, and in many positions residues are found that are more characteristic of alpha- and beta-globins, suggesting a conservation of residues over a long period of evolutionary time.
Abstract: Myoglobin isolated from red muscle of the shark H. portusjacksoni was purified by ion-exchange chromatography on sulfopropyl-Sephadex and gel-filtration. Amino acid analysis and sequence determination showed 148 amino acid residues. The amino terminal residue is acetylated as shown by mass spectrographic analysis of N-terminal peptides. There is a deletion of four residues at the amino terminal end as well as one residue in the CD interhelical area relative to other myoglobins.
Journal Article•
TL;DR: The reliability of serum myoglobin as a marker for acute myocardial infarction was evaluated in 157 consecutive coronary-care admissions and an elevated myoglobin was elevated in association with angina, congestive heart failure, arrhythmias, and renal insufficiency.
Abstract: The reliability of serum myoglobin as a marker for acute myocardial infarction was evaluated in 157 consecutive coronary-care admissions. Admission myoglobin was elevated in 47 of 52 patients with acute infarction. Excluding those patients who presented later than 24 hr after symptom onset, only one patient with acute infarct had a normal admission myoglobin. In 22 of 105 patients with no infarct, myoglobin was elevated in association with angina, congestive heart failure, arrhythmias, and renal insufficiency. The detection of acute infarction by serum myoglobin measurement equals that of serial serum creatine phosphokinase isoenzymes (CPK-MB) by electrophoresis, but an elevated myoglobin is not specific for what is now considered clinically significant myocardial infarction.
Journal Article•
TL;DR: It is suggested that protein pl and urine pH are important in determining nephrotoxicity; a mechanism by which these low molecular weight serum proteins and TAMM-HORSFALL proteins interact in the distal nephron to initiate acute renal failure in postulated.
Abstract: Three types of low molecular weight serum proteins, myoglobin, hemoglobin and BENCE-JONES proteins, are associated clinically with acute renal failure. All have isoelectric points which render them anionic at blood pH but cationic in the distal nephron under conditions of aciduria. Experiments in which these proteins were mixed with TAMM-HORSFALL mucoprotein in vitro and the pH lowered with lN HCl showed co-precipitation of proteins at pH levels of 5.5 and below. In vivo experiments in which 11 different BENCE-JONES proteins of pl ranging from 5.2 to 6.6 were injected into aciduric, hydropenic rats showed an acute rise in serum urea nitrogen and creatinine concentrations with BENCE-JONES proteins of pl greater than 5.7 compared with little change in rats injected with BENCE-JONES proteins of pl less than 5.7. These data suggest that protein pl and urine pH are important in determining nephrotoxicity; a mechanism by which these low molecular weight serum proteins and TAMM-HORSFALL proteins interact in the distal nephron to initiate acute renal failure in postulated.
TL;DR: The molecular variants of the myoglobins of Paramecium tetraurelia have been purified as five separate components and designated Mb 1 to Mb 5, which appear to have identical molecular weights and amino acid compositions and differ only in their isoelectric points and relative concentrations in vivo.
Abstract: 1. 1. The molecular variants of the myoglobins of Paramecium tetraurelia have been purified as five separate components and designated Mb 1 to Mb 5. 2. 2. The five molecular forms are homogeneous on polyacrylamide gel electrophoresis (PAGE) and isoelectric focusing (IF). 3. 3. The myoglobin species appear to have identical molecular weights and amino acid compositions and differ only in their isoelectric points and relative concentrations in vivo. 4. 4. The myoglobin species have an apparent molecular weight of 15,000 ± 500 and possess a single heme group per mole which appears to be protoporphyrin IX. 5. 5. The amino acid composition of the five species is: lys12, his3, arg4, asp17, thr9, ser6, glu16, pro4, gly11, ala15, cys0, val8, met2, ile7, leu10, tyr5, phe7. 6. 6. The spectra of several ferrous and ferric derivatives of the mixture Mb 1–Mb 5 are presented.
TL;DR: In twenty patients admitted to hospital with the clinical diagnosis acute myocardial infarction, the serum myoglobin concentration profiles were in close agreement with the final diagnosis.
Abstract: A radioimmunoassay for quantitation of serum myoglobin in healthy individuals and patients with different diseases is described. Purified myoglobin was labelled by an 125I-labelled ester (N-succinimidyl 3-(-4 hydroxy, 5-[125I]iodophenyl) propionate), a commercially available antiserum was used, and the antigen-antibody complex was precipitated with polyethylene glycol 6000. The rapid assay can be performed within 1 h at 37 degrees C with a detection limit of 45 micrograms/l. Prolonged incubation at 4 degrees C for 18 or 72 h gives a detection limit of 6 and 2 micrograms/l, respectively. The mean coefficient of variation of the routine assay was 11%. In healthy human subjects a significant difference in mean serum myoglobin concentration was found between 43 women (34 +/- 17 micrograms/l) and 51 mean 47 +/- 15 micrograms/l). In twenty patients admitted to hospital with the clinical diagnosis acute myocardial infarction, the serum myoglobin concentration profiles were in close agreement with the final diagnosis. In three patients with myocardial infarction serum samples were taken every 2 h after the acute episode, and serum myoglobin levels were compared with the levels of creatine kinase, lactate dehydrogenase, aspartate aminotransferase and creatine kinase isoenzyme-MB.