Elsevier

Methods in Enzymology

Volume 52, 1978, Pages 97-101
Methods in Enzymology

[8] Purification of cytochrome b5

https://doi.org/10.1016/S0076-6879(78)52010-7Get rights and content

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This chapter provides information on the purification of cytochrome b5. The isolation of cytochrome b5 from liver endoplasmic reticulum in its complete form requires fractionation procedures with detergents at 0° to avoid loss of peptide fragments by endopeptidase activity. The chapter mentions the procedure for the heme peptide and NADH-cytochrome b5 reductase that can also be used for the complete form of cytochrome b5. NADH and the reductase are added to the cytochrome to yield the reduced spectrum. This procedure is the one that gradually evolved from the original procedure described for rabbit liver. To scale the preparation to large amounts of yearling steer liver, CaCI2 precipitation of microsomes and slightly different column chromatography steps are employed. Cytochrome b5 serves as an electron acceptor for cytochrome b5 reductase and an electron donor for stearyl-CoA desaturase where the binding of the protein to phospholipid.

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