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Solomon EI, Heppner DE, Johnston EM, Ginsbach JW, Cirera J, Qayyum M, Kieber-Emmons MT, Kjaergaard CH, Hadt RG, Tian L. Copper active sites in biology. Chem Rev 2014; 114:3659-853. [PMID: 24588098 PMCID: PMC4040215 DOI: 10.1021/cr400327t] [Citation(s) in RCA: 1129] [Impact Index Per Article: 112.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
| | - David E. Heppner
- Department of Chemistry, Stanford University, Stanford, CA, 94305
| | | | - Jake W. Ginsbach
- Department of Chemistry, Stanford University, Stanford, CA, 94305
| | - Jordi Cirera
- Department of Chemistry, Stanford University, Stanford, CA, 94305
| | - Munzarin Qayyum
- Department of Chemistry, Stanford University, Stanford, CA, 94305
| | | | | | - Ryan G. Hadt
- Department of Chemistry, Stanford University, Stanford, CA, 94305
| | - Li Tian
- Department of Chemistry, Stanford University, Stanford, CA, 94305
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Behrens JW, Elias JP, Taylor HH, Weber RE. The archaeogastropod mollusc Haliotis iris: tissue and blood metabolites and allosteric regulation of haemocyanin function. J Exp Biol 2002; 205:253-63. [PMID: 11821491 DOI: 10.1242/jeb.205.2.253] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
We investigated divalent cation and anaerobic end-product concentrations and the interactive effects of these substances and pH on haemocyanin oxygen-binding (Hc-O2) in the New Zealand abalone Haliotis iris. During 24 h of environmental hypoxia (emersion), d-lactate and tauropine accumulated in the foot and shell adductor muscles and in the haemolymph of the aorta, the pedal sinus and adductor muscle lacunae, whereas l-lactate was not detected. Intramuscular and haemolymph d-lactate concentrations were similar, but tauropine accumulated to much higher levels in muscle tissues. Repeated disturbance and short-term exposure to air over 3 h induced no accumulation of d- or l-lactate and no change in [Ca2+], [Mg2+], pH and O2-binding properties of the native haemolymph.
The haemolymph showed a low Hc-O2 affinity, a large reverse Bohr effect and marked cooperativity. Dialysis increased Hc-O2 affinity, obliterated cooperativity and decreased the pH-sensitivity of O2 binding. Replacing Mg2+ and Ca2+ restored the native O2-binding properties and the reverse Bohr shift. l- and d-lactate exerted minor modulatory effects on O2-affinity. At in vivo concentrations of Mg2+ and Ca2+, the cooperativity is dependent largely on Mg2+, which modulates the O2 association equilibrium constants of both the high-affinity (KR) and the low-affinity (KT) states (increasing and decreasing, respectively). This allosteric mechanism contrasts with that encountered in other haemocyanins and haemoglobins. The functional properties of H. iris haemocyanin suggest that high rates of O2 delivery to the tissues are not a priority but are consistent with the provision of a large O2 reserve for facultatively anaerobic tissues during internal hypoxia associated with clamping to the substratum.
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Affiliation(s)
- Jane W Behrens
- Department of Zoophysiology, Institute Biological Sciences, University of Aarhus, DK 8000 Aarhus, Denmark
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