TY - JOUR
T1 - Oxygenation and EPR spectral properties of Aplysia myoglobins containing cobaltous porphyrins
AU - Ikeda-Saito, Masao
AU - Brunori, Maurizio
AU - Yonetani, Takashi
N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 1978/3/28
Y1 - 1978/3/28
N2 - Cobalt myoglobins (Aplysia) have been reconstituted from apo-myoglobin (Aplysia) and proto-, meso-, and deutero-cobalt porphyrins. Each of them showed the 30-60 times lower oxygen affinity than those of the corresponding cobalt myoglobins (Sperm whale). Kinetic investigation of their oxygenation by the temperature-jump relaxation technique showed that the low oxygen affinity of cobalt myoglobin (Aplysia) is due to a large dissociation rate constant. The electron paramagnetic resonance (EPR) spectrum of oxy cobalt myoglobin (Aplysia) is affected by the replacement of H2O with D2O, suggesting a possible interaction between the bound oxygen and the neighboring hydrogen atom. A low temperature photodissociation study showed that the product of photolysis of oxy cobalt myoglobin (Aplysia) gives an EPR spectrum different from that of the deoxy-cobalt myoglobin (Aplysia) and from that of the photo-lysed form of oxy-cohalt myogloin (Sperm whale). These observations suggest that in oxy-cobalt myoglobin (Aplysia) the bound oxygen might interact with amino acid adjacent to it, but the interaction is weaker than that in oxy cobalt myoglobin (Sperm whale).
AB - Cobalt myoglobins (Aplysia) have been reconstituted from apo-myoglobin (Aplysia) and proto-, meso-, and deutero-cobalt porphyrins. Each of them showed the 30-60 times lower oxygen affinity than those of the corresponding cobalt myoglobins (Sperm whale). Kinetic investigation of their oxygenation by the temperature-jump relaxation technique showed that the low oxygen affinity of cobalt myoglobin (Aplysia) is due to a large dissociation rate constant. The electron paramagnetic resonance (EPR) spectrum of oxy cobalt myoglobin (Aplysia) is affected by the replacement of H2O with D2O, suggesting a possible interaction between the bound oxygen and the neighboring hydrogen atom. A low temperature photodissociation study showed that the product of photolysis of oxy cobalt myoglobin (Aplysia) gives an EPR spectrum different from that of the deoxy-cobalt myoglobin (Aplysia) and from that of the photo-lysed form of oxy-cohalt myogloin (Sperm whale). These observations suggest that in oxy-cobalt myoglobin (Aplysia) the bound oxygen might interact with amino acid adjacent to it, but the interaction is weaker than that in oxy cobalt myoglobin (Sperm whale).
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U2 - 10.1016/0005-2795(78)90561-5
DO - 10.1016/0005-2795(78)90561-5
M3 - Article
C2 - 205264
AN - SCOPUS:0017835365
VL - 533
SP - 173
EP - 180
JO - BBA - Protein Structure
JF - BBA - Protein Structure
SN - 1570-9639
IS - 1
ER -