Membrane environment drives cytochrome P450's spin transition and its interaction with cytochrome b5.
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ABSTRACT:
SUBMITTER: Ravula T
PROVIDER: S-EPMC5710748 | biostudies-literature | 2017 Nov
REPOSITORIES: biostudies-literature
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Membrane environment drives cytochrome P450's spin transition and its interaction with cytochrome b<sub>5</sub>.
Ravula Thirupathi T Barnaba Carlo C Mahajan Mukesh M Anantharamaiah G M GM Im Sang-Choul SC Waskell Lucy L Ramamoorthy Ayyalusamy A
Chemical communications (Cambridge, England) 20171101 95
Heme's spin-multiplicity is key in determining the enzymatic function of cytochrome P450 (cytP450). The origin of the low-spin state in ferric P450 is still under debate. Here, we report the first experimental demonstration of P450's membrane interaction altering its spin equilibrium which is accompanied by a stronger affinity for cytochrome b<sub>5</sub>. These results highlight the importance of lipid membrane for the function of P450. ...[more]
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