Education

PhD   Biochemistry    West Virginia University       Morgantown, WV 

BA     Chemistry     Western Maryland College     Westminster, MD

Associations

American Medical Association
American Society for Pharmacology and Experimental Therapeutics
International Society for the Study of Xenobiotics
American Society for Biochemistry and Molecular Biology

Publications

Fuchs, R.M., Reed, J.R., Paloncýová, M., Šrejber, M., Čechová, P., Otyepka, M., Eyer, M.K. and Backes, W.L. (2024) Identification of the N-terminal residues responsible for the differential microdomain localization of CYP1A1 and CYP1A2. Journal of Biological Chemistry 300 (11) 107891.

Cawley, G.F., Connick, J.P., and Backes, W.L. (2024) Environmentally Persistent Free Radicals inhibit CYP2E1 monooxygenase activities by reaction uncoupling:  Production of reactive oxygen species are stimulated at the expense of substrate metabolism. Drug Metabolism and Disposition DMD-AR-2024-001939; DOI: https://doi.org/10.1124/dmd.124.001939.

Connick, J.P., Stepter, A., Cawley, G.F., Eyer, M.K., and Backes, W.L. (2024) Environmentally Persistent Free Radicals lead to selective inhibition of CYP1 monooxygenase activities, and increased production of Reactive Oxygen species by Reaction Uncoupling. Frontiers in Public Health (2025) DOI: 10.3389/fpubh.2025.1531134.

Huber III, W.J., Scruggs, B., and Backes, W.L. (2009) C-Terminal Membrane Spanning Region of Human Heme Oxygenase-1 Mediates a Time Dependent Complex Formation with Cytochrome P450 Reductase, Biochemistry 41, 190-197 (PMCID: PMC2789667).

Huber III, W.J., Marohnic, C.C., Peters, M., Alam, J., Reed, J.R., Masters, B.S.S., and Backes, W.L. (2009) Measurement of Membrane-Bound Human Heme Oxygenase-1 Activity Using a Chemically Defined Assay System, Drug Metab. Dispos. 37, 857-864 (PMCID: PMC2680543).

Reed, J.R., Eyer, M., and Backes, W.L. (2010) Functional Interactions between Cytochromes P450 1A2 and 2B4 Require Both Enzymes to Reside in the Same Phospholipid Vesicle: Evidence for physical complex formation, J. Biol. Chem. 285, 8942-8952 (PMCID: PMC2838316).

Reed, J.R., Huber, W.J., and Backes, W.L. (2010) Human Heme Oxygenase-1 Efficiently Catabolizes Heme in the Absence of Biliverdin Reductase, Drug Metab. Dispos. 38, 2060-2066 (PMCID: PMC2967390).

Reed, J.R., Cawley, G.F., and Backes, W.L. (2011) Inhibition of Cytochrome P450 1A2-Mediated Metabolism and Production of Reactive Oxygen Species by Heme Oxygenase-1 in Rat Liver Microsomes, Drug Metabolism Letters, 5, 6-16 (PMCID: PMC3252637).

Brignac-Huber, L., Reed, J.R., and Backes, W.L. (2011) Organization of NADPH-Cytochrome P450 Reductase and CYP1A2 in the Endoplasmic Reticulum – Microdomain localization affects monooxygenase function, Mol. Pharmacol. 79, 549-557 (PMCID: PMC3061359).

Marohnic, C.C., Huber, W.J. III, Connick, J.P., Reed, J.R., McCammon, K., Panda, S.P., Martásek, P., Backes, W.L., and Masters, B.S.S. (2011) Mutations of Human Cytochrome P450 Reductase Differentially Modulate Heme Oxygenase-I Activity and Oligomerization, Arch. Biochem. Biophys. 513, 42-50 (PMCID: PMC3516858).

Reed, J.R., Connick, J.P., Cheng, D., Cawley, G.F., and Backes, W.L. (2012) Effect of Homomeric P450•P450 Complexes on P450 Function, Biochem. J. 446, 489-497 (PMID: 22738171; PMCID:PMC3518449).

Reed, J.R. and Backes, W.L. (2012) Formation of P450•P450 Complexes and Their Effect on P450 Function, Pharmacology and Therapeutics 133, 299-310 (PMID: 22155419; PMCID: PMC3272114).

Reed, J.R., Cawley, G.F., and Backes, W.L. (2013) Interactions between CYP2B4 and CYP1A2 Lead to Alterations in Toluene Disposition and P450 Uncoupling, Biochemistry 52, 4003-4013 (PMID: 23675771; PMCID:PMC3750074).

Brignac-Huber, L., Reed, J.R., and Backes, W.L. (2013) Relationship between CYP1A2 Localization and Lipid Microdomain Formation as a Function of Lipid Composition, Drug Metabolism and Disposition 41, 1896-1905 (PMCID: PMC3807054).

Johnson, E.F., Connick, J.P., Reed, J.R., Backes, W.L., Desai, M.C., Xu, L., Estrada, R., Laurence, J.S., and Scott, E.E. (2014) Correlating Structure and Function of Drug-Metabolizing Enzymes: Progress and Ongoing Challenges, Drug Metabolism and Disposition 42, 9-22 (PMID:24130370 PMCID:PMC3876788).

Park, J.-W., Reed, J.R., and Backes, W.L. (2014) Cytochrome P450 system proteins reside in different regions of the endoplasmic reticulum, Biochem. J. 464, 241-249 (PMID:25236845; PMCID: PMC4314108).

Reed, J.R., Cawley, G.F., Ardoin, T.G., Dellinger, B., Lomnicki, S.M., Hasan, F., Kiruri, L.W. and Backes, W.L. (2014) Environmentally Persistent Free Radicals Inhibit Cytochromes P450 Activity in Rat Liver Microsomes, Toxicology and Applied Pharmacology 277, 200-209 (PMID: 24713513; PMCID: PMC4049543). 

Reed, J.R., Ardoin, T.G., dela Cruz, A. Lomnicki, S.M. and Backes, W.L. (2015) Inhibition of Cytochrome P450 2B4 by Environmentally Persistent Free Radical-containing Nanoparticles, Biochem. Pharmacol. 95, 126-132. (PMID: 25817938; PMCID: PMC4406862). 

Park, J.-W., Reed, J.R., and Backes, W.L. (2015) The Localization of Cytochrome P450s CYP1A1 and CYP1A2 into Different Lipid Microdomains is Governed by their N-terminal and Internal Protein Regions, J. Biol. Chem. 290, 29449-29460 (PMID: 26468279; PMCID: PMC4705947.

Reed, J.R., dela Cruz, A.L.N., Lomnicki, S.M., and Backes, W.L. (2015) Environmentally persistent free radical-containing particulate matter competitively inhibits metabolism by cytochrome P450 1A2, Toxicol. Appl. Pharmacol. 289, 223-230 (PMID: 26423927; PMCID: PMC4651829).

Scott, E.E., Wolf, C.R., Otyepka, M., Humphreys, S.C., Reed, J.R., Henderson, C.J., McLaughlin, L.A., Paloncýová, M., Navrátilová, V., Berka, K., Anzenbacher, P., Dahal, U.P., Barnaba, C., Brozik, J.A., Jones, J.P., Estrada, D.F., Laurence, J.S., Park, J.W. and Backes, W.L. (2016) The Role of Protein-Protein and Protein-Membrane Interactions on P450 Function, Drug Metabolism and Disposition 44, 1-15 (PMCID: PMC4810767).

Reed, J.R. and Backes, W.L. (2017) Physical studies of P450-P450 interactions: Predicting quaternary structures of P450 complexes in membranes from their X-ray crystal structures, Frontiers of Pharmacology, https://doi.org/10.3389.fphar.2017.00028 (PMCID: PMC5276844).

Pandey, A.V., Henderson, C.J., Ishii, Y., Dranendonk, M., Backes, W.L., Zanger, U.M. (2017) Editorial: Role of protein-protein interactions in metabolism: Genetics, structure, function.  Frontiers in Pharmacology https://doi.org/10.3389/fphar.2017.00881.  PMCID PMC5712015).

Connick, J.P., Reed, J.R., and Backes, W.L. (2018) Characterization of interactions among CYP1A2, CYP2B4, and NADPH-cytochrome P450 reductase: Identification of specific protein complexes. Drug Metabolism and Disposition 46, 197-203. DOI: https://doi.org/10.1124/dmd.117.078642; PMCID: PMC5797933

Harmon, A.C., Hebert, V.Y., Cormier, S.A., Subramanian, B., Reed, J.R., Backes, W.L., and Dugas, T.R. (2018) Particulate matter containing environmentally persistent free radicals induces AhR-dependent cytokine and reactive oxygen species production in human bronchial epithelial cells. PLoS One 13, e0205412. https://doi.org/10.1371/journal.pone.0205412; PMCID:PMC6182347  

Connick, J.P., Reed, J.R., Cawley, G.F., and Backes, W.L. (2020)  Heme oxygenase-1 affects cytochrome P450 function through the formation of heteromeric complexes: Interactions between CYP1A2 and heme oxygenase-1. J. Biol. Chem. 296, 100030; PMCID PMC7948974; https://doi.org/10.1074/jbc.RA120.015911.

Connick, J.P., Reed, J.R., Cawley, G.F., and Backes, W.L. (2021) Heteromeric complex formation between human cytochrome P450 CYP1A1 and heme oxygenase-1.  Biochem. J. 478, 377-388; DOI: https://doi.org/10.1042/BCJ20200768; PMCID: PMC8552777

Saha, A., Connick, J.P., Reed, J.R., Lott, C.S., and Backes, W.L. (2021) Identification of the contact region for the CYP1A2•CYP1A2 complex: The region proximal to the heme disrupts its interaction with P450 reductase. Biochemical Journal 478, 2163-2178, DOI https://doi.org/10.1042/BCJ20210269; PMCID:PMC8522333

Reed, J.R., Guidry, J.J., and Backes, W.L. (2022) Proteomic and bioinformatics analysis of membrane lipid domains after Brij 98 solubilization of uninduced and phenobarbital-induced rat liver microsomes: Defining the membrane localization of the P450 enzyme system.  Drug Metabolism and Disposition 50, (4) 374-385; DOI: https://doi.org/10.1124/dmd.121.000752; (NIHMS1797558).

Reed, J.R., Guidry, J.J., and Backes, W.L. (2023) The influence of lipid microdomain heterogeneity on protein-protein interactions: Proteomic analysis of co-immunoprecipitated binding partners of P450 1A2 and P450 3A in rat liver microsomes.  Drug Metabolism and Disposition 51, 1196-1206; https://dmd.aspetjournals.org/content/early/2023/06/22/dmd.123.001287).

Connick, J.P., Reed, J.R., Cawley, G.F., Saha, A., and Backes, W.L. (2023) Functional characterization of CYP1 enzymes: Complex formation, membrane localization and function. Journal of Inorganic Biochemistry 247, 112325 https://www.sciencedirect.com/science/article/pii/S0162013423002076

Research

Drug Metabolism 

Dr. Backes' research focuses on understanding how P450 system proteins are organized in the endoplasmic reticulum, and how their organization affects monooxygenase function.  His research also examines how protein-lipid interactions influence the localization of P450 system proteins in the endoplasmic reticulum.  Biological membranes are heterogeneous in nature, being comprised of ordered membrane regions enriched in cholesterol and sphingomyelin and phospholipids containing more-saturated fatty acids, and disordered membranes containing more-unsaturated phospholipids.  A goal of this area of research is to identify the amino acid segments that are responsible for raft and non-raft targeting of ER proteins. 

 School of Medicine Research

Lab

Research Interests

Cytochrome P450 refers to a superfamily of heme-containing enzymes involved in the metabolism of a wide variety of drugs, hydrocarbons, and other foreign compounds. This enzyme system is capable of metabolizing substrates of widely varying structure, with the basic process to insert an oxygen atom into the substrate molecule. The resulting product is more water soluble and generally more rapidly excreted; however, some of the resulting metabolites are reactive and can covalently bind to DNA, RNA and proteins. The bioactivation of foreign compounds by cytochrome P450 and some other xenobiotic-metabolizing enzymes can lead to toxicity, mutagenesis, carcinogenesis, and birth defects.

There are two reasons the cytochrome P450 system can metabolize a wide variety of substrates. First, the active site of cytochrome P450 is relatively non-selective and is capable of accommodating substrates of diverse chemical structures. The second reason for its broad selectivity is that there are many different P450 enzymes, each with their own characteristic substrate selectivities. Each of the P450 enzymes is independently regulated at least in part, by nutritional status, and prior exposure to foreign compounds.

The enzymes of the cytochrome P450 system do not act alone, but are part of an electron transport chain found in the endoplasmic reticulum. P450 requires an interaction with NADPH-cytochrome P450 reductase, a flavoprotein that is necessary for the transfer the reducing equivalents to P450. Other proteins that interact with those of the P450 system include cytochrome b5, NADH-cytochrome b5 reductase, and heme oxygenase.

An important characteristic of the P450 system that can influence its catalytic effectiveness is that, in most tissues, P450 is present in a large molar excess over the reductase. This creates conditions where a particular P450 enzyme will need to effectively compete with other P450 enzymes for the available reductase or be metabolically silent. The resulting metabolism of a foreign compound by the P450 system will depend on which P450 enzymes most effectively receive electrons from the reductase. A diagram of the problem is shown where multiple P450 enzymes and other enzymes must compete for the reductase.