The main objective of the proposed research is to determine the structure of a 16.7 kDa membrane-associated cytochrome-b5, an electron transfer protein found in a variety of cell types. It plays a major role in the catalytic activity of cytochrome-P450, which metabolizes more than 50% of the drugs in clinical use today. It is also involved as an electron transfer component in a number of oxidative reactions in biological tissues, which includes the anabolic metabolism of fats and steroids. It presents significant challenges for experimental techniques of protein structure determination. However, structure determination of membrane proteins by NMR spectroscopy is in a rapid phase of development;recent results on several membrane proteins are promising and indicate that the structure determination of cytochrome-b5 is feasible. The structure of cytochrome-b5 will be determined in micelles by solution NMR and in lipid bilayers by solid state NMR techniques. Structures obtained in free and in complexation with cytochrome-P450 will provide insights into the molecular mechanism by which cytochrome-b5 influences the catalysis of cytochrome-P450.

Public Health Relevance

The outcome of the proposed structural studies on cytochrome-b5 will provide insights into molecular mechanism by which cytochrome-b5 influences oxidation by cytochrome- P450 that metabolizes more than 50% of current-day drugs. These studies will also enable us to understand the role of cytochrome-b5 in the biosynthesis of testosterone and numerous unsaturated lipids, which are necessary for maintaining the integrity of cellular membranes.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Research Project (R01)
Project #
Application #
Study Section
Biochemistry and Biophysics of Membranes Study Section (BBM)
Program Officer
Okita, Richard T
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Michigan Ann Arbor
Schools of Arts and Sciences
Ann Arbor
United States
Zip Code
Yamamoto, Kazutoshi; Caporini, Marc A; Im, Sang-Choul et al. (2015) Cellular solid-state NMR investigation of a membrane protein using dynamic nuclear polarization. Biochim Biophys Acta 1848:342-9
Zhang, Rongchun; Damron, Joshua; Vosegaard, Thomas et al. (2015) A cross-polarization based rotating-frame separated-local-field NMR experiment under ultrafast MAS conditions. J Magn Reson 250:37-44
Nishiyama, Yusuke; Malon, Michal; Ishii, Yuji et al. (2014) 3D ¹?N/¹?N/¹H chemical shift correlation experiment utilizing an RFDR-based ¹H/¹H mixing period at 100 kHz MAS. J Magn Reson 244:1-5
Kotler, Samuel A; Walsh, Patrick; Brender, Jeffrey R et al. (2014) Differences between amyloid-? aggregation in solution and on the membrane: insights into elucidation of the mechanistic details of Alzheimer's disease. Chem Soc Rev 43:6692-700
Yamamoto, Kazutoshi; Pearcy, Paige; Ramamoorthy, Ayyalusamy (2014) Bicelles exhibiting magnetic alignment for a broader range of temperatures: a solid-state NMR study. Langmuir 30:1622-9
Tsukamoto, Manami; Kuroda, Kenichi; Ramamoorthy, Ayyalusamy et al. (2014) Modulation of raft domains in a lipid bilayer by boundary-active curcumin. Chem Commun (Camb) 50:3427-30
Nishiyama, Yusuke; Zhang, Rongchun; Ramamoorthy, Ayyalusamy (2014) Finite-pulse radio frequency driven recoupling with phase cycling for 2D (1)H/(1)H correlation at ultrafast MAS frequencies. J Magn Reson 243:25-32
Vivekanandan, Subramanian; Ahuja, Shivani; Im, Sang-Choul et al. (2014) ¹H, ¹³C and ¹?N resonance assignments for the full-length mammalian cytochrome b? in a membrane environment. Biomol NMR Assign 8:409-13
Huang, Rui; Yamamoto, Kazutoshi; Zhang, Meng et al. (2014) Probing the transmembrane structure and dynamics of microsomal NADPH-cytochrome P450 oxidoreductase by solid-state NMR. Biophys J 106:2126-33
DeToma, Alaina S; Krishnamoorthy, Janarthanan; Nam, Younwoo et al. (2014) Synthetic Flavonoids, Aminoisoflavones: Interaction and Reactivity with Metal-Free and Metal-Associated Amyloid-? Species. Chem Sci 5:4851-4862

Showing the most recent 10 out of 43 publications