Oxygen binding characteristics of lobster hemocyanin and its subunits

Johnston, W. W.; James, Thomas W.; Barber, Albert A.

doi:10.1016/0010-406x(67)90186-7

Cited by 23 publications

(3 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Limulus polyphemus He was collected and frozen at the Woods Hole Oceanographic Institute, Woods Hole, MA, and was purified as described above for C. maenas He, Panulirus interruptus He was collected at the Biomarine Lab, Venice, CA, and was purified according to a published procedure (Johnston et al, 1967). Apo-Hcs (containing less than 5% of the copper content of holo-Hc) were prepared from holo-Hc by dialysis against cyanide and EDTA, as described elsewhere (Salvato et al, 1974).…”

Section: Methodsmentioning

confidence: 99%

Preparation and spectroscopic characterization of a coupled binuclear center in cobalt(II)-substituted hemocyanin

Bubacco¹,

Magliozzo²,

Beltramini³

et al. 1992

Biochemistry

View full text Add to dashboard Cite

A binuclear cobalt derivative of arthropod hemocyanin (Hc) has been prepared by the reaction of apo-Hc with Co(II) in the presence of thiocyanate. The crude product of the reaction contains specifically and adventitiously bound metal, the latter being removable by EDTA treatment. The specifically bound Co(II) constitutes a binuclear metal center that exhibits optical and CD spectra typical in their absorption maxima and extinction coefficients of Co(II) complexes with near-tetrahedral geometry. The EPR spectrum of the binuclear Co(II) derivative contains a resonance at g approximately 13, which is characteristic of integer spin systems and indicates coupled metal ions; the excess Co(II) bound to crude products exhibits an EPR signal at g approximately 4. The time course of derivative formation was followed by EPR, optical and atomic absorption techniques, and by fluorimetry. The intensity of the optical absorption in the visible region due to Co(II) increases with increasing stoichiometry of specifically bound metal [up to 2 Co(II) per protein monomer], but the intensity of the Co(II) EPR signal increases only during the formation of a mononuclear derivative. As the reaction proceeds over approximately 100 h to the formation of the binuclear derivative, the EPR signal intensity decreases to 10% of the value expected for 2 mol of EPR-active Co(II)/mol of protein. The binuclear cobalt derivative cannot be reconstituted to native Hc with Cu(I), indicating the stable loading of Co(II) in the active site. EPR and optical spectroscopic evidence is presented showing that the binuclear derivative does not bind oxygen.

show abstract

Section: Methodsmentioning

confidence: 99%

Preparation and spectroscopic characterization of a coupled binuclear center in cobalt(II)-substituted hemocyanin

Bubacco¹,

Magliozzo²,

Beltramini³

et al. 1992

Biochemistry

View full text Add to dashboard Cite

show abstract

“…These were determined by a technique similar to that described by Riggs (1951), with the addition of an oxygen electrode in the tonometer as described by Johnston et al (1967). The tonometer was made from a 100-ml three-necked distilling flask.…”

Section: Oxygen Equilibrium Curves Of Hemoglobin Solutionsmentioning

confidence: 99%

Temperature-induced changes in the oxygen equilibrium curve of the blood of the brown bullhead, Ictalurus nebulosus

Grigg

1969

Comparative Biochemistry and Physiology

View full text Add to dashboard Cite

Abstract-1. The affinity of blood for oxygen is dependent on temperature, which would seem to present a disadvantage to those fishes which encounter large seasonal temperature changes. Considering the well-known acclimatory abilities of many fishes, it would seem reasonable to propose the occurrence of seasonal modification of blood oxygen equilibria to compensate for changes in temperature.2. In Ictalurus nebulosus, blood from one group of fish acclimated at 24°C showed a consistently higher oxygen affinity compared with a group acclimated at 9°C, when measured at the same temperature. This shift, accompanying thermal metabolic acclimation, minimizes the effect of temperature on oxygen affinity.3. The shift did not persist when dilute solutions of hemoglobin were studied. 4. No changes with acclimation were seen in the multiple hemoglobin pattern nor in blood pH. 5. The erythrocyte, rather than the plasma, appears to be the site of modification. 6. Some large changes in erythrocyte potassium accompanied thermal acclimation, but the relation of this to the shift in oxygen affinity is unknown.

show abstract

“…A common property exhibited by all haemocyanins, so far examined in this respect, is their ability to exist in solution in a variety of polymeric forms, the extent of polymerization depending upon environmental factors, such as pH and ionic strength (Brohult, 1940). Several workers have commented upon the possible relation between sigmoidal binding curves observed with different types of haemocyanin and the known polymerization reactions of the proteins (e.g., Larimer and Riggs, 1964;Johnston et al, 1967). The present study attempts to examine the validity of the postulated relationship for the particular system, oxygen-Jams lalandii haemocyanin.…”

mentioning

confidence: 99%

Polymerization behavior of Jasus lalandii hemocyanin and its relation to the allosteric binding of oxygen

Moore¹,

Henderson²,

Nichol³

1968

Biochemistry

View full text Add to dashboard Cite

Oxygen binding characteristics of lobster hemocyanin and its subunits

Cited by 23 publications

References 18 publications

Preparation and spectroscopic characterization of a coupled binuclear center in cobalt(II)-substituted hemocyanin

Preparation and spectroscopic characterization of a coupled binuclear center in cobalt(II)-substituted hemocyanin

Temperature-induced changes in the oxygen equilibrium curve of the blood of the brown bullhead, Ictalurus nebulosus

Polymerization behavior of Jasus lalandii hemocyanin and its relation to the allosteric binding of oxygen

Contact Info

Product

Resources

About