Browse
Submit Data
Databases
API
Help

Dataset Information

17 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Functional consequences of haem orientational disorder in sperm-whale and yellow-fin-tuna myoglobins.

ABSTRACT: Ligand-binding kinetics of native and reconstituted sperm-whale myoglobin were studied in relation to haem orientational disorder by rapid kinetic methods. In addition, native yellow-fin-tuna myoglobin with significant amount of haem disorder was also used. The O2 dissociation and association rates were found for the proteins with different degrees of haem disorder, and these results suggest that the isomers are characterized by almost identical kinetic parameters. Rates of CO recombination after photolysis were also identical for the two orientational isomers. The results clearly indicate that the rotation of the haem about the alpha-gamma meso axis has little or no effect on the ligand-binding properties of these myoglobins.

SUBMITTER: Aojula HS

PROVIDER: S-EPMC1147833 | biostudies-other | 1987 Apr

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

1H-n.m.r. and c.d. studies of haem orientational disorder in sperm-whale myoglobin and human haemoglobin.

Project description:1H-n.m.r. and c.d. studies on sperm-whale myoglobin show that the c.d. signal in the Soret region is inversely and linearly related to the proportion of minor isomer present. An alternative method, 'pH jump', is described for inducing orientational disorder in sperm-whale myoglobin without recourse to reconstitution. 1H-n.m.r. studies on human haemoglobin A indicate little heterogeneity in freshly isolated haemoglobin A, but the effect is enhanced in freeze-dried Sigma haemoglobin A.

| S-EPMC1148933 | biostudies-other

Reaction of variant sperm-whale myoglobins with hydrogen peroxide: the effects of mutating a histidine residue in the haem distal pocket.

Project description:The reaction of hydrogen peroxide with a number of variants of sperm-whale myoglobin in which the distal pocket histidine residue (His64) had been mutated was studied with a combination of stopped-flow spectroscopy and freeze-quench EPR. The rate of the initial bimolecular reaction with hydrogen peroxide in all the proteins studied was found to depend on the polarity of the amino acid side chain at position 64. In wild-type myoglobin there were no significant optical changes subsequent to this reaction, suggesting the rapid formation of the well-characterized oxyferryl species. This conclusion was supported by freeze-quench EPR data, which were consistent with the pattern of reactivity previously reported [King and Winfield (1963) J. Biol. Chem. 238, 1520-1528]. In those myoglobins bearing a mutation at position 64, the initial bimolecular reaction with hydrogen peroxide yielded an intermediate species that subsequently decayed via a second hydrogen peroxide-dependent step leading to modification or destruction of the haem. In the mutant His64-->Gln the calculated electronic absorption spectrum of the intermediate was not that of an oxyferryl species but seemed to be that of a low-spin ferric haem. Freeze-quench EPR studies of this mutant and the apolar mutant (His64-->Val) revealed the accumulation of a novel intermediate after the first hydrogen peroxide-dependent reaction. The unusual EPR characteristics of this species are provisionally assigned to a low-spin ferric haem with bound peroxide as the distal ligand. These results are interpreted in terms of a reaction scheme in which the polarity of the distal pocket governs the rate of binding of hydrogen peroxide to the haem iron and the residue at position 64 governs both the rate of heterolytic oxygen scission and the stability of the oxyferryl product.

| S-EPMC1218643 | biostudies-other

Immunochemistry of sperm-whale myoglobins prepared with various modified porphyrins and metalloporphyrins.

Project description:1. The preparation and characterization of manganese, iron, cobalt, nickel, copper and zinc metalloporphyrins is described. Ferrihaem was also esterified with pyrid-4-ylpropanol and the derivative characterized as the diester. 2. Complexes of these various porphyrins, as well as protoporphyrin IX, with apomyoglobin were formed and the resulting artificial myoglobins characterized. 3. Very little complex-formation was obtained with nickel, cobalt and manganese metalloporphyrins and apomyoglobin. 4. Myoglobin prepared with copper metalloporphyrin was immunochemically identical with native ferrimyoglobin. All the other artificial myoglobins were less reactive to varying degrees. 5. The changes in antigenic reactivities were attributed to conformational reorganization caused by the different co-ordination tendencies of the various metals or by the modification of the side chains of the haem.

| S-EPMC1270364 | biostudies-other

Haem disorder in two myoglobins: comparison of reorientation rate.

Project description:The globins from sperm whale and from Aplysia limacina myoglobins were reconstituted by addition of stoichiometric ferric protohaem and the Soret c.d. was followed as a function of time. For both reconstituted proteins, the Soret c.d. changes with time, reflecting haem reorientation inside its pocket, as previously described [Aojula, Wilson & Drake (1986) Biochem. J. 237, 613-616] for sperm whale myoglobin. The time course of the c.d. transition is found to be approx. 10 times faster in Aplysia than in sperm whale myoglobin, a result which is in agreement with the known structural and physicochemical properties of the two myoglobins; furthermore, these results confirm that c.d. and n.m.r. data on haem orientation in haemoproteins reflect the same molecular phenomenon.

| S-EPMC1148347 | biostudies-other

Haem disorder in modified myoglobins. Effect of reconstitution procedures.

Project description:Apomyoglobin was reconstituted with deuterohaem derivatives under various conditions. The fraction of disordered component, which is characterized by a 180 degree rotation of the haem group, for the various preparations was determined by n.m.r. spectroscopy. By using the procedures described, it was shown that the fraction of disordered component is minimized if the reconstitution is carried out with high-spin ferric haem derivatives within an experimentally determined optimum pH range of 8-9.5. Use of low-spin derivatives in either the ferrous or ferric forms leads to substantial increases in the fraction of disordered form. Attempted removal of the disordered form by selective oxidation and chromatographic purification was not effective.

| S-EPMC1152370 | biostudies-other

Blue Whale and Fin Whale

Project description:Balaenoptera musculus (Blue Whale) and Balaenoptera physalus (Fin Whale) Genome sequencing and assembly

| PRJNA704862 | ENA

Fin whale singing decreases with increased swimming speed.

Project description:The attributes of male acoustic advertisement displays are often related to a performer's age, breeding condition and motivation, but these relationships are particularly difficult to study in free-ranging marine mammals. For fin whale singers, we examined the relationships between a singer's swimming speed, song duration and amount of singing. We used a unique set of fin whale singing and swimming data collected in support of the US Navy's marine mammal monitoring programme associated with the Navy's Integrated Undersea Surveillance System. A goal of the programme is to improve understanding of the potential effects of anthropogenic sound sources on baleen whale behaviours and populations. We found that as whales swam faster, some continued to sing, while others did not. If swimming speed is an indication of male stamina, then singing while swimming faster could be a display by which females and/or other males assess a singer's physical fitness and potential reproductive quality. Results have implications for interpreting fin whale singing behaviour and the possible influences of anthropogenic sounds on fin whale mating strategies and breeding success.

| S-EPMC6599786 | biostudies-literature

Fin whale sound reception mechanisms: skull vibration enables low-frequency hearing.

Project description:Hearing mechanisms in baleen whales (Mysticeti) are essentially unknown but their vocalization frequencies overlap with anthropogenic sound sources. Synthetic audiograms were generated for a fin whale by applying finite element modeling tools to X-ray computed tomography (CT) scans. We CT scanned the head of a small fin whale (Balaenoptera physalus) in a scanner designed for solid-fuel rocket motors. Our computer (finite element) modeling toolkit allowed us to visualize what occurs when sounds interact with the anatomic geometry of the whale's head. Simulations reveal two mechanisms that excite both bony ear complexes, (1) the skull-vibration enabled bone conduction mechanism and (2) a pressure mechanism transmitted through soft tissues. Bone conduction is the predominant mechanism. The mass density of the bony ear complexes and their firmly embedded attachments to the skull are universal across the Mysticeti, suggesting that sound reception mechanisms are similar in all baleen whales. Interactions between incident sound waves and the skull cause deformations that induce motion in each bony ear complex, resulting in best hearing sensitivity for low-frequency sounds. This predominant low-frequency sensitivity has significant implications for assessing mysticete exposure levels to anthropogenic sounds. The din of man-made ocean noise has increased steadily over the past half century. Our results provide valuable data for U.S. regulatory agencies and concerned large-scale industrial users of the ocean environment. This study transforms our understanding of baleen whale hearing and provides a means to predict auditory sensitivity across a broad spectrum of sound frequencies.

| S-EPMC4310601 | biostudies-literature

Absorption spectra of sperm-whale ferrimyoglobin.

Project description:1. Sperm-whale ferrimyoglobin was found to contain 0.308% of Fe, on a dry weight basis, corresponding to a molecular weight of 18130. The solid takes up moisture to an equilibrium state, and was then assayed to contain 0.280% of Fe. 2. Absorption spectra are presented for acidic ferrimyoglobin, Fe(+)(H(2)O), and its conjugate base, Fe-OH, as well as for the fluoride and cyanide complexes, within the range 200-2500mmu. Data for ferromyoglobin-carbon monoxide, Fe(II)-CO, in the visible region are also included. 3. Minor spectral differences have been found between whale and horse myoglobins, particularly in the effect of temperature on the visible-absorption spectrum of Fe-OH.

| S-EPMC1264813 | biostudies-other

Fin whale song variability in southern California and the Gulf of California.

Project description:Songs are distinct, patterned sounds produced by a variety of animals including baleen whales. Fin whale songs, which consist of short pulses repeated at regular interpulse intervals (IPIs), have been suggested as a tool to distinguish populations. Fin whale songs were analyzed from data collected from 2000-2012 in Southern California and from 2004-2010 in the Gulf of California using autonomous acoustic recorders. IPIs were measured for each identifiable song sequence during two random days of each month with recordings. Four distinct song types were identified: long doublet, short doublet, long triplet, and short triplet. Long and short doublets were the dominant songs in Southern California, while long and short triplets were dominant in the Gulf of California. An abrupt change in song type occurred in both areas during the monitoring period. We argue that each song type is unique to a population and these changes represent a shift in the primary population in the monitoring area. Occasional temporal and spatial song overlap indicated some exchange or visitation among populations. Fin whales appear to synchronize and gradually modify song rhythm over long time scales. A better understanding of the evolutionary and ecological importance of songs to fin whale populations is needed.

| S-EPMC5579205 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data