Functional and conformational modulation of human cytochrome P450 1B1 by anionic phospholipids.
We investigated the interaction of human P450 1B1 (CYP1B1) with various phospholipid bilayers using the N-terminally deleted (Delta2-4)CYP1B1 and (Delta2-26)CYP1B1 enzymes. Among anionic phospholipids, phosphatidic acid (PA) and cardiolipin specifically increased the catalytic activities, membrane binding affinities, and thermal stabilities of both CYP1B1 proteins when phosphatidylcholine matrix was gradually replaced with these anionic phospholipids. PA- or cardiolipin-dependent changes of CYP1B1 conformation were revealed by altered Trp fluorescence and CD spectra. However, both PA and cardiolipin exerted more significant effects with the (Delta2-4)CYP1B1 than the (Delta2-26)CYP1B1 implying the functional importance of N-terminal region for the interaction with the phospholipid membranes. In contrast, other anionic phospholipids such as phosphatidylserine and the neutral phospholipid phosphatidylethanolamine had no apparent effects on the catalytic activity or conformation of CYP1B1. These data suggest that the chemical and physical properties of membranes influenced by PA or cardiolipin composition are critical for the functional roles of CYP1B1.
Jang
Hyun-Hee
HH
School of Biological Sciences and Technology, Chonnam National University, Gwangju, Republic of Korea.
Kim
Dong-Hyun
DH
Ahn
Taeho
T
Yun
Chul-Ho
CH
D001189:Aryl Hydrocarbon Hydroxylases; D002384:Catalysis; D002942:Circular Dichroism; D065633:Cytochrome P-450 CYP1B1; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism*; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism*; D017434:Protein Structure, Tertiary / Q000502:physiology
D008051:Lipid Bilayers; D010743:Phospholipids; D003577:Cytochrome P-450 Enzyme System; D001189:Aryl Hydrocarbon Hydroxylases; C585496:CYP1B1 protein, human; D065633:Cytochrome P-450 CYP1B1