Demonstration by 2H ENDOR spectroscopy that myo-inositol binds via an alkoxide bridge to the mixed-valent diiron center of myo-inositol oxygenase.
myo-Inositol oxygenase (MIOX) is a non-heme diiron oxygenase that cleaves cyclohexane-(1,2,3,5/4,6-hexa)-ol (myo-inositol, MI) to d-glucuronate. Here, we use 2H ENDOR spectroscopy to demonstrate that MI binds to the diiron(II/III) cofactor of MIOX via an alkoxide bridge, most likely involving O1. Analysis shows that MI adopts a symmetrical geometry in which the O-C-2H plane of the bridge is approximately orthogonal to the Fe-O-Fe plane.
Kim
Sun Hee
SH
Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Xing
Gang
G
Bollinger
J Martin
JM
Krebs
Carsten
C
Hoffman
Brian M
BM
D007294:Inositol / Q000737:chemistry* / Q000378:metabolism; D050562:Inositol Oxygenase / Q000737:chemistry* / Q000378:metabolism; D007501:Iron / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008956:Models, Chemical; D015394:Molecular Structure; D011485:Protein Binding
D007294:Inositol; D007501:Iron; D050562:Inositol Oxygenase