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Richard AM, Estrada DF, Flynn L, Pochapsky SS, Scott EE, Pochapsky TC. Tracking protein-protein interactions by NMR: conformational selection in human steroidogenic cytochrome P450 CYP17A1 induced by cytochrome b5. Phys Chem Chem Phys 2024; 26:16980-16988. [PMID: 38842434 PMCID: PMC11186455 DOI: 10.1039/d4cp01268b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 05/26/2024] [Indexed: 06/07/2024]
Abstract
The human steroidogenic cytochrome P450 CYP17A1 catalyzes two types of reactions in the biosynthetic pathway leading from pregnenolone to testosterone and several other steroid hormones. The first is the hydroxylation of pregnenolone or progesterone to the corresponding 17α-hydroxy steroid, followed by a lyase reaction that converts these 17α-hydroxy intermediates to the androgens dehydroepiandrosterone and androstenedione, respectively. cytochrome b5 (cytb5) is known to act as both an effector and electron donor for the lyase oxidations, markedly stimulating the rate of the lyase reaction in its presence relative to the rate in its absence. Extensive sequential backbone 1H,15N and 13C nuclear magnetic resonance assignments have now been made for oxidized CYP17A1 bound to the prostate cancer drug and inhibitor abiraterone. This is the first eukaryotic P450 for which such assignments are now available. These assignments allow more complete interpretation of the structural perturbations observed upon cytb5 addition. Possible mechanism(s) for the effector activity of cytb5 are discussed in light of this new information.
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Affiliation(s)
- Alaina M Richard
- Chemical Biology Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - D Fernando Estrada
- Department of Medicinal Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, Kansas 66045, USA
| | - Liam Flynn
- Department of Chemistry, Brandeis University, 415 South St., Waltham, MA 02454-9110, USA.
| | - Susan Sondej Pochapsky
- Department of Chemistry, Brandeis University, 415 South St., Waltham, MA 02454-9110, USA.
| | - Emily E Scott
- Chemical Biology Program, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Medicinal Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, Kansas 66045, USA
- Departments of Medicinal Chemistry, Pharmacology, and Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Thomas C Pochapsky
- Department of Chemistry, Brandeis University, 415 South St., Waltham, MA 02454-9110, USA.
- Department of Biochemistry and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, 415 South St., Waltham, MA 02454-9110, USA
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Tateishi Y, Webb SN, Li B, Liu L, Lindsey Rose K, Leser M, Patel P, Guengerich FP. Proteomics, modeling, and fluorescence assays delineate cytochrome b 5 residues involved in binding and stimulation of cytochrome P450 17A1 17,20-lyase. J Biol Chem 2024; 300:105688. [PMID: 38280431 PMCID: PMC10878793 DOI: 10.1016/j.jbc.2024.105688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 01/15/2024] [Accepted: 01/18/2024] [Indexed: 01/29/2024] Open
Abstract
Cytochrome b5 (b5) is known to stimulate some catalytic activities of cytochrome P450 (P450, CYP) enzymes, although mechanisms still need to be defined. The reactions most strongly enhanced by b5 are the 17,20-lyase reactions of P450 17A1 involved in steroid biosynthesis. We had previously used a fluorescently labeled human b5 variant (Alexa 488-T70C-b5) to characterize human P450 17A1-b5 interactions, but subsequent proteomic analyses indicated that lysines in b5 were also modified with Alexa 488 maleimide in addition to Cys-70, due to disulfide dimerization of the T70C mutant. A series of b5 variants were constructed with Cys replacements for the identified lysine residues and labeled with the dye. Fluorescence attenuation and the function of b5 in the steroid lyase reaction depended on the modified position. Apo-b5 (devoid of heme group) studies revealed the lack of involvement of the b5 heme in the fluorescence attenuation. A structural model of b5 with P450 17A1 was predicted using AlphaFold-Multimer algorithms/Rosetta docking, based upon the individual structures, which predicted several new contacts not previously reported, that is, interactions of b5 Glu-48:17A1 Arg-347, b5 Glu-49:17A1 Arg-449, b5 Asp-65:17A1 Arg-126, b5 Asp-65:17A1 Arg-125, and b5 Glu-61:17A1 Lys-91. Fluorescence polarization assays with two modified b5 variants yielded Kd values (for b5-P450 17A1) of 120 to 380 nM, the best estimate of binding affinity. We conclude that both monomeric and dimeric b5 can bind to P450 17A1 and stimulate activity. Results with the mutants indicate that several Lys residues in b5 are sensitive to the interaction with P450 17A1, including Lys-88 and Lys-91.
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Affiliation(s)
- Yasuhiro Tateishi
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Stephany N Webb
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Bian Li
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Lu Liu
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Kristie Lindsey Rose
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, USA; Proteomics Laboratory, Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Micheal Leser
- Proteomics Laboratory, Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Purvi Patel
- Proteomics Laboratory, Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
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Tumilovich A, Yablokov E, Mezentsev Y, Ershov P, Basina V, Gnedenko O, Kaluzhskiy L, Tsybruk T, Grabovec I, Kisel M, Shabunya P, Soloveva N, Vavilov N, Gilep A, Ivanov A. The Multienzyme Complex Nature of Dehydroepiandrosterone Sulfate Biosynthesis. Int J Mol Sci 2024; 25:2072. [PMID: 38396748 PMCID: PMC10889563 DOI: 10.3390/ijms25042072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/16/2024] [Accepted: 01/26/2024] [Indexed: 02/25/2024] Open
Abstract
Dehydroepiandrosterone (DHEA), a precursor of steroid sex hormones, is synthesized by steroid 17-alpha-hydroxylase/17,20-lyase (CYP17A1) with the participation of microsomal cytochrome b5 (CYB5A) and cytochrome P450 reductase (CPR), followed by sulfation by two cytosolic sulfotransferases, SULT1E1 and SULT2A1, for storage and transport to tissues in which its synthesis is not available. The involvement of CYP17A1 and SULTs in these successive reactions led us to consider the possible interaction of SULTs with DHEA-producing CYP17A1 and its redox partners. Text mining analysis, protein-protein network analysis, and gene co-expression analysis were performed to determine the relationships between SULTs and microsomal CYP isoforms. For the first time, using surface plasmon resonance, we detected interactions between CYP17A1 and SULT2A1 or SULT1E1. SULTs also interacted with CYB5A and CPR. The interaction parameters of SULT2A1/CYP17A1 and SULT2A1/CYB5A complexes seemed to be modulated by 3'-phosphoadenosine-5'-phosphosulfate (PAPS). Affinity purification, combined with mass spectrometry (AP-MS), allowed us to identify a spectrum of SULT1E1 potential protein partners, including CYB5A. We showed that the enzymatic activity of SULTs increased in the presence of only CYP17A1 or CYP17A1 and CYB5A mixture. The structures of CYP17A1/SULT1E1 and CYB5A/SULT1E1 complexes were predicted. Our data provide novel fundamental information about the organization of microsomal CYP-dependent macromolecular complexes.
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Affiliation(s)
- Anastasiya Tumilovich
- Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus; (A.T.); (T.T.); (I.G.); (M.K.); (P.S.); (A.G.)
| | - Evgeniy Yablokov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; (E.Y.); (P.E.); (O.G.); (L.K.); (N.S.); (N.V.); (A.I.)
| | - Yuri Mezentsev
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; (E.Y.); (P.E.); (O.G.); (L.K.); (N.S.); (N.V.); (A.I.)
| | - Pavel Ershov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; (E.Y.); (P.E.); (O.G.); (L.K.); (N.S.); (N.V.); (A.I.)
| | - Viktoriia Basina
- Research Centre for Medical Genetics, 1 Moskvorechye Street, 115522 Moscow, Russia;
| | - Oksana Gnedenko
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; (E.Y.); (P.E.); (O.G.); (L.K.); (N.S.); (N.V.); (A.I.)
| | - Leonid Kaluzhskiy
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; (E.Y.); (P.E.); (O.G.); (L.K.); (N.S.); (N.V.); (A.I.)
| | - Tatsiana Tsybruk
- Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus; (A.T.); (T.T.); (I.G.); (M.K.); (P.S.); (A.G.)
| | - Irina Grabovec
- Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus; (A.T.); (T.T.); (I.G.); (M.K.); (P.S.); (A.G.)
| | - Maryia Kisel
- Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus; (A.T.); (T.T.); (I.G.); (M.K.); (P.S.); (A.G.)
| | - Polina Shabunya
- Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus; (A.T.); (T.T.); (I.G.); (M.K.); (P.S.); (A.G.)
| | - Natalia Soloveva
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; (E.Y.); (P.E.); (O.G.); (L.K.); (N.S.); (N.V.); (A.I.)
| | - Nikita Vavilov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; (E.Y.); (P.E.); (O.G.); (L.K.); (N.S.); (N.V.); (A.I.)
| | - Andrei Gilep
- Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus; (A.T.); (T.T.); (I.G.); (M.K.); (P.S.); (A.G.)
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; (E.Y.); (P.E.); (O.G.); (L.K.); (N.S.); (N.V.); (A.I.)
| | - Alexis Ivanov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; (E.Y.); (P.E.); (O.G.); (L.K.); (N.S.); (N.V.); (A.I.)
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Wróbel TM, Jørgensen FS, Pandey AV, Grudzińska A, Sharma K, Yakubu J, Björkling F. Non-steroidal CYP17A1 Inhibitors: Discovery and Assessment. J Med Chem 2023; 66:6542-6566. [PMID: 37191389 DOI: 10.1021/acs.jmedchem.3c00442] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
CYP17A1 is an enzyme that plays a major role in steroidogenesis and is critically involved in the biosynthesis of steroid hormones. Therefore, it remains an attractive target in several serious hormone-dependent cancer diseases, such as prostate cancer and breast cancer. The medicinal chemistry community has been committed to the discovery and development of CYP17A1 inhibitors for many years, particularly for the treatment of castration-resistant prostate cancer. The current Perspective reflects upon the discovery and evaluation of non-steroidal CYP17A1 inhibitors from a medicinal chemistry angle. Emphasis is placed on the structural aspects of the target, key learnings from the presented chemotypes, and design guidelines for future inhibitors.
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Affiliation(s)
- Tomasz M Wróbel
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances, Faculty of Pharmacy, Medical University of Lublin, Chodźki 4a, 20093 Lublin, Poland
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Flemming Steen Jørgensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Amit V Pandey
- Pediatric Endocrinology, Department of Pediatrics, University Children's Hospital, Inselspital, Bern and Translational Hormone Research Program, Department of Biomedical Research, University of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Angelika Grudzińska
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances, Faculty of Pharmacy, Medical University of Lublin, Chodźki 4a, 20093 Lublin, Poland
| | - Katyayani Sharma
- Pediatric Endocrinology, Department of Pediatrics, University Children's Hospital, Inselspital, Bern and Translational Hormone Research Program, Department of Biomedical Research, University of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Jibira Yakubu
- Pediatric Endocrinology, Department of Pediatrics, University Children's Hospital, Inselspital, Bern and Translational Hormone Research Program, Department of Biomedical Research, University of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Fredrik Björkling
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Guengerich FP, McCarty KD, Tateishi Y, Liu L. Steroid 17α-hydroxylase/17, 20-lyase (cytochrome P450 17A1). Methods Enzymol 2023; 689:39-63. [PMID: 37802581 DOI: 10.1016/bs.mie.2023.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Cytochrome P450 (P450) 17A1 plays a key role in steroidogenesis, in that this enzyme catalyzes the 17α-hydroxylation of both pregnenolone and progesterone, followed by a lyase reaction to cleave the C-20 land C-21 carbons from each steroid. The reactions are important in the production of both glucocorticoids and androgens. The enzyme is critical in humans but is also a drug target in treatment of prostate cancer. Detailed methods are described for the heterologous expression of human P450 17A1 in bacteria, purification of the recombinant enzyme, reconstitution of the enzyme system in the presence of cytochrome b5, and chromatographic procedures for sensitive analyses of reaction products. Historic assay approaches are reviewed. Some information is also provided about outstanding questions in the research field, including catalytic mechanisms and searches for selective inhibitors.
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Affiliation(s)
- F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, United States.
| | - Kevin D McCarty
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Yasuhiro Tateishi
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Lu Liu
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, United States
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6
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Guengerich FP. On 'Evidence for the participation of cytochrome b5 in hepatic microsomal mixed-function oxidation reactions' by Alfred Hildebrandt and Ronald W. Estabrook. Arch Biochem Biophys 2022; 726:109177. [PMID: 35305998 PMCID: PMC9893037 DOI: 10.1016/j.abb.2022.109177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 03/10/2022] [Indexed: 02/04/2023]
Abstract
This paper by Alfred G. Hildebrandt and Ronald W. Estabrook at the University of Texas (Southwestern) Medical School, led to the concept of cytochrome b5 (b5) as an auxiliary protein facilitating some cytochrome P450 (P450) reactions in the liver and other tissues. The gist of the paper is that DPNH (now known as NADH) enhanced rates of TPNH (now NADPH)-supported N-demethylation of O-ethylmorphine in rat liver microsomes. The conclusion was that b5 was providing an electron to the ferrous-oxy form of P450 (Fe2+O2), which was supported by some spectral observations on the oxidation state of b5 in the microsomes in the steady state. This observation led to a flurry of activity, which is still in progress. This paper has been cited 678 times in Google (558 in Clarivate), and I have often cited it myself. A PubMed search for the terms P450 andb5 yielded 2244 results.
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Affiliation(s)
- F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, 638B Robinson Research Bldg, 2200 Pierce Avenue, Nashville, TN, 37232-0146, USA.
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7
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Singh H, Kumar R, Mazumder A, Salahuddin, Mazumder R, Abdullah MM. Insights into Interactions of Human Cytochrome P450 17A1: Review. Curr Drug Metab 2022; 23:172-187. [DOI: 10.2174/1389200223666220401093833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 01/15/2022] [Accepted: 02/04/2022] [Indexed: 11/22/2022]
Abstract
Abstract:
Cytochrome P450s are a widespread and vast superfamily of hemeprotein monooxygenases that metabolize physiologically essential chemicals necessary for most species' survival, from protists to plants to humans. They catalyze the synthesis of steroid hormones, cholesterol, bile acids, and arachidonate metabolites and the degradation of endogenous compounds such as steroids, fatty acids, and other catabolizing compounds as an energy source and detoxifying xenobiotics such as drugs, procarcinogens, and carcinogens. The human CYP17A1 is one of the cytochrome P450 genes located at the 10q chromosome. The gene expression occurs in the adrenals and gonads, with minor amounts in the brain, placenta, and heart. This P450c17 cytochrome gene is a critical steroidogenesis regulator which performs two distinct activities: 17 alpha-hydroxylase activity (converting pregnenolone to 17-hydroxypregnenolone and progesterone to 17-hydroxyprogesterone, these precursors are further processed to provide glucocorticoids and sex hormones) and 17, 20-lyase activity (which converts 17-hydroxypregnenolone to DHEA). Dozens of mutations within CYP17A1 are found to cause 17-alpha-hydroxylase and 17, 20-lyase deficiency. This condition affects the function of certain hormone-producing glands, resulting in high blood pressure levels (hypertension), abnormal sexual development, and other deficiency diseases. This review highlights the changes in CYP17A1 associated with gene-gene interaction, drug-gene interaction, chemical-gene interaction, and its biochemical reactions; they have some insights to correlate with the fascinating functional characteristics of this human steroidogenic gene. The findings of our theoretical results will be helpful to further the design of specific inhibitors of CYP17A1.
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Affiliation(s)
- Himanshu Singh
- Department of Pharmaceutical Chemistry, Noida Institute of Engineering and Technology (Pharmacy Institute), Greater Noida, India
| | - Rajnish Kumar
- Department of Pharmaceutical Chemistry, Noida Institute of Engineering and Technology (Pharmacy Institute), Greater Noida, India
| | - Avijit Mazumder
- Department of Pharmaceutical Chemistry, Noida Institute of Engineering and Technology (Pharmacy Institute), Greater Noida, India
| | - Salahuddin
- Department of Pharmaceutical Chemistry, Noida Institute of Engineering and Technology (Pharmacy Institute), Greater Noida, India
| | - Rupa Mazumder
- Department of Pharmaceutical Chemistry, Noida Institute of Engineering and Technology (Pharmacy Institute), Greater Noida, India
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Yamagata S, Kageyama K, Usui T, Saito K, Takayasu S, Usutani M, Terui K, Daimon M. Identification of a homozygous c.1039C>T (p.R347C) variant in CYP17A1 in a 67-year-old female patient with partial 17α-hydroxylase/17,20-lyase deficiency. Endocr J 2022; 69:115-120. [PMID: 34483146 DOI: 10.1507/endocrj.ej21-0266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
17α-Hydroxylase/17,20-lyase deficiency (17OHD) is caused by pathogenic mutations in CYP17A1. Impaired 17α-hydroxylase and 17,20-lyase activities typically induce hypertension, hypokalemia, sexual infantilism, and amenorrhea. Most patients with 17OHD are diagnosed in adolescence. Here, we report a female (46, XX) patient with 17OHD who was diagnosed at the age of 67 years. Genetic analysis was performed using direct DNA sequencing of polymerase chain reaction (PCR) products and multiplex ligation-dependent probe amplification (MLPA) analysis. Direct DNA sequencing revealed a homozygous c.1039C>T in CYP17A1, corresponding to a p.R347C amino acid change. MLPA probe signals showed that the CYP17A1 mutation was present in the homozygous carrier state. The patient's dehydroepiandrosterone sulfate and androstenedione levels were extremely low, despite elevated adrenocorticotropic hormone (ACTH) and normal cortisol levels. A corticotropin-releasing hormone (CRH) test showed no response of cortisol, despite a normal response of ACTH. Rapid ACTH injection resulted in elevations in the deoxycorticosterone, corticosterone, aldosterone, and 17-hydroxypregnenolone levels, but not in the cortisol level. These results suggested that 17α-hydroxylase/17,20-lyase activities were partially impaired. Computed tomography revealed bilateral adrenal hyperplasia and a hypoplastic uterus. A high basal plasma ACTH level and a discrepancy between ACTH and cortisol responses in a CRH test may provide a definitive diagnostic clue for this disease.
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Affiliation(s)
- Satoshi Yamagata
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
| | - Kazunori Kageyama
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
| | - Takeshi Usui
- Department of Medical Genetics, Shizuoka General Hospital, Shizuoka 420-8527, Japan
- Shizuoka Graduate University of Public Health, Shizuoka 420-0881, Japan
| | - Kohei Saito
- Department of Medical Genetics, Shizuoka General Hospital, Shizuoka 420-8527, Japan
| | - Shinobu Takayasu
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
| | - Mari Usutani
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
| | - Ken Terui
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
| | - Makoto Daimon
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
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9
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Zhang D, Yao F, Luo M, Wang Y, Tian T, Deng S, Tian Q. Clinical characteristics and molecular etiology of partial 17α-hydroxylase deficiency diagnosed in 46,XX patients. Front Endocrinol (Lausanne) 2022; 13:978026. [PMID: 36589849 PMCID: PMC9797673 DOI: 10.3389/fendo.2022.978026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Accepted: 11/21/2022] [Indexed: 12/16/2022] Open
Abstract
INTRODUCTION Complete 17α-hydroxylase deficiency (17OHD) is relatively common, with typical juvenile female genitalia, severe hypertension, hypokalemia, and the absence of sexual development, but partial (or non-classical) 17OHD (p17OHD) is extremely rare. The p17OHD patients can present with a broad spectrum of symptoms in 46,XX karyotype including various degree of spontaneous breast development after puberty, recurrent ovarian cysts, oligomenorrhea and infertility depending on specific gene mutations and other influencing factors. METHODS This paper is a retrospective analysis of p17OHD cases from 1997 to 2021 in a Chinese tertiary hospital. Eight patients were recruited from unrelated families according to clinical data. Genotypes of patients were determined by sequencing the CYP17A1 genes. Clinical characteristics were summarized based on manifestations, hormone profiles, and responses to treatments. RESULTS All seven post-pubertal patients had abnormal menses. All patients had enlarged multilocular ovaries, and six (6/8) had a history of ovarian cystectomy prior to a definite diagnosis of p17OHD. All eight patients' sex hormone levels were in accord to hypogonadism with mildly elevated follicle-stimulating hormone levels, and oral contraceptives effectively suppressed the ovarian cysts. Of the four patients who underwent plasma renin activity tests, all showed results below the reference range. Fourteen alleles with a CYP17A1 mutation were found. Exon 6 was the most frequent mutation site (5/14), and four out of these five mutations were c.985_987delTACinsAA, being the most common one. In Case 2, c.1220dupA was a newly reported mutation of CYP17A1. CONCLUSIONS 46,XX p17OHD patients were born with highly fragile ovarian reserve due to diverse mutations of CYP17A1. However, their multi-ovarian cysts can be managed conservatively for fertility preservation. This study focuses on p17OHD in 46,XX by locating the complex genetic causes in novel mutations, summarizing the puzzling spectrum of clinical manifestations, and illustrating the significance of fertility preservation in these scarce cases.
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Affiliation(s)
- Duoduo Zhang
- Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Fengxia Yao
- Clinical Research Laboratory, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Min Luo
- Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Yanfang Wang
- Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Tiffany Tian
- Department of Biology, Emory College of Arts and Sciences, Atlanta, GA, United States
| | - Shan Deng
- Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Qinjie Tian
- Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
- Center for Rare Diseases Research, Chinese Academy of Medical Sciences, Beijing, China
- *Correspondence: Qinjie Tian,
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10
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McGuire MR, Mukhopadhyay D, Myers SL, Mosher EP, Brookheart RT, Kammers K, Sehgal A, Selen ES, Wolfgang MJ, Bumpus NN, Espenshade PJ. Progesterone receptor membrane component 1 (PGRMC1) binds and stabilizes cytochromes P450 through a heme-independent mechanism. J Biol Chem 2021; 297:101316. [PMID: 34678314 PMCID: PMC8591507 DOI: 10.1016/j.jbc.2021.101316] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 10/12/2021] [Accepted: 10/18/2021] [Indexed: 12/03/2022] Open
Abstract
Progesterone receptor membrane component 1 (PGRMC1) is a heme-binding protein implicated in a wide range of cellular functions. We previously showed that PGRMC1 binds to cytochromes P450 in yeast and mammalian cells and supports their activity. Recently, the paralog PGRMC2 was shown to function as a heme chaperone. The extent of PGRMC1 function in cytochrome P450 biology and whether PGRMC1 is also a heme chaperone are unknown. Here, we examined the function of Pgrmc1 in mouse liver using a knockout model and found that Pgrmc1 binds and stabilizes a broad range of cytochromes P450 in a heme-independent manner. Proteomic and transcriptomic studies demonstrated that Pgrmc1 binds more than 13 cytochromes P450 and supports maintenance of cytochrome P450 protein levels posttranscriptionally. In vitro assays confirmed that Pgrmc1 KO livers exhibit reduced cytochrome P450 activity consistent with reduced enzyme levels. Mechanistic studies in cultured cells demonstrated that PGRMC1 stabilizes cytochromes P450 and that binding and stabilization do not require PGRMC1 binding to heme. Importantly, Pgrmc1-dependent stabilization of cytochromes P450 is physiologically relevant, as Pgrmc1 deletion protected mice from acetaminophen-induced liver injury. Finally, evaluation of Y113F mutant Pgrmc1, which lacks the axial heme iron-coordinating hydroxyl group, revealed that proper iron coordination is not required for heme binding, but is required for binding to ferrochelatase, the final enzyme in heme biosynthesis. PGRMC1 was recently identified as the causative mutation in X-linked isolated pediatric cataract formation. Together, these results demonstrate a heme-independent function for PGRMC1 in cytochrome P450 stability that may underlie clinical phenotypes.
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Affiliation(s)
- Meredith R McGuire
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Debaditya Mukhopadhyay
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Stephanie L Myers
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Eric P Mosher
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Rita T Brookheart
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kai Kammers
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Alfica Sehgal
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ebru S Selen
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Michael J Wolfgang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Namandjé N Bumpus
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peter J Espenshade
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
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11
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Kim D, Kim V, Tateishi Y, Guengerich FP. Cytochrome b 5 Binds Tightly to Several Human Cytochrome P450 Enzymes. Drug Metab Dispos 2021; 49:902-909. [PMID: 34330716 DOI: 10.1124/dmd.121.000475] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 07/13/2021] [Indexed: 01/18/2023] Open
Abstract
Numerous studies have been reported in the past 50-plus years regarding the stimulatory role of cytochrome b 5 (b 5) in some, but not all, microsomal cytochrome P450 (P450) reactions with drugs and steroids. A missing element in most of these studies has been a sensitive and accurate measure of binding affinities of b 5 with P450s. In the course of work with P450 17A1, we developed a fluorescent derivative of a human b 5 site-directed mutant, Alexa 488-T70C-b 5, that could be used in binding assays at sub-μM concentrations. Alexa 488-T70C-b 5 bound to human P450s 1A2, 2B6, 2C8, 2C9, 2E1, 2S1, 4A11, 3A4, and 17A1, with estimated K d values ranging from 2.5 to 61 nM. Only weak binding was detected with P450 2D6, and no fluorescence attenuation was observed with P450 2A6. All of the P450s that bound b 5 have some reported activity stimulation except for P450 2S1. The affinity of P450 3A4 for b 5 was decreased somewhat by the presence of a substrate or inhibitor. The fluorescence of a P450 3A4•Alexa 488-T70C-b 5 complex was partially restored by titration with NADPH-P450 reductase (POR) (K d,apparent 89 nM), suggesting the existence of a ternary P450 3A4-b 5-POR complex, as observed previously with P450 17A1. Gel filtration evidence was also obtained for this ternary complex with P450 3A4. Overall, the results indicated that the affinity of b 5 for many P450s is very high, and that ternary P450-b 5-POR complexes are relevant in P450 3A4 reactions as opposed to a shuttle mechanism. SIGNIFICANCE STATEMENT: High-affinity binding of cytochrome b 5 (b 5) (K d < 100 nM) was observed with many drug-metabolizing cytochrome P450 (P450) enzymes. There is some correlation of binding with reported stimulation, with several exceptions. Evidence is provided for a ternary P450 3A4-b 5-NADPH-P450 reductase complex.
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Affiliation(s)
- Donghak Kim
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 (D.K., Y.T., F.P.G.), and Department of Biological Sciences, Konkuk University, Seoul, Republic of Korea (D.K., V.K.)
| | - Vitchan Kim
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 (D.K., Y.T., F.P.G.), and Department of Biological Sciences, Konkuk University, Seoul, Republic of Korea (D.K., V.K.)
| | - Yasuhiro Tateishi
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 (D.K., Y.T., F.P.G.), and Department of Biological Sciences, Konkuk University, Seoul, Republic of Korea (D.K., V.K.)
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 (D.K., Y.T., F.P.G.), and Department of Biological Sciences, Konkuk University, Seoul, Republic of Korea (D.K., V.K.)
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12
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Baker JE, Plaska SW, Qin Z, Liu CJ, Rege J, Rainey WE, Udager AM. Targeted RNA sequencing of adrenal zones using immunohistochemistry-guided capture of formalin-fixed paraffin-embedded tissue. Mol Cell Endocrinol 2021; 530:111296. [PMID: 33915228 PMCID: PMC8456741 DOI: 10.1016/j.mce.2021.111296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 04/05/2021] [Accepted: 04/20/2021] [Indexed: 10/21/2022]
Abstract
Adequate access to fresh or frozen normal adrenal tissue has been a primary limitation to the enhanced characterization of the adrenal zones via RNA sequencing (RNAseq). Herein, we describe the application of targeted RNAseq to formalin-fixed paraffin-embedded (FFPE) normal adrenal gland specimens. Immunohistochemistry (IHC) was used to visualize and guide the capture of the adrenocortical zones and medulla. Following IHC-based tissue capture and isolation of RNA, high-throughput targeted RNAseq highlighted clear transcriptomic differences and identified differentially expressed genes among the adrenal zones. Our data demonstrate the ability to capture FFPE adrenal zone tissue for targeted transcriptomic analyses. Future comparison of normal adrenal zones will improve our understanding of transcriptomic patterns and help identify potential novel pathways controlling zone-specific steroid production.
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Affiliation(s)
- Jessica E Baker
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Samuel W Plaska
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Zhaoping Qin
- Department of Internal Medicine, Division of Hematology/Oncology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Chia-Jen Liu
- Michigan Center for Translational Pathology, Ann Arbor, MI, USA
| | - Juilee Rege
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - William E Rainey
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA; Rogel Cancer Center, University of Michigan, Ann Arbor, MI, USA; Department of Internal Medicine, Division of Metabolism, Endocrine, and Diabetes, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Aaron M Udager
- Michigan Center for Translational Pathology, Ann Arbor, MI, USA; Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA; Rogel Cancer Center, University of Michigan, Ann Arbor, MI, USA.
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13
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Kim D, Kim V, McCarty KD, Guengerich FP. Tight binding of cytochrome b 5 to cytochrome P450 17A1 is a critical feature of stimulation of C21 steroid lyase activity and androgen synthesis. J Biol Chem 2021; 296:100571. [PMID: 33753170 PMCID: PMC8080067 DOI: 10.1016/j.jbc.2021.100571] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/16/2021] [Accepted: 03/18/2021] [Indexed: 12/19/2022] Open
Abstract
It has been recognized for >50 years that cytochrome b5 (b5) stimulates some cytochrome P450 (P450)–catalyzed oxidations, but the basis of this function is still not understood well. The strongest stimulation of catalytic activity by b5 is in the P450 17A1 lyase reaction, an essential step in androgen synthesis from 21-carbon (C21) steroids, making this an excellent model system to interrogate b5 function. One of the issues in studying b5–P450 interactions has been the limited solution assay methods. We constructed a fluorescently labeled variant of human b5 that can be used in titrations. The labeled b5 bound to WT P450 17A1 with a Kd of 2.5 nM and rapid kinetics, on the order of 1 s−1. Only weak binding was observed with the clinical P450 17A1 variants E305G, R347H, and R358Q; these mutants are deficient in lyase activity, which has been hypothesized to be due to attenuated b5 binding. Kd values were not affected by the presence of P450 17A1 substrates. A peptide containing the P450 17A1 Arg-347/Arg-358 region attenuated Alexa 488-T70C-b5 fluorescence at higher concentrations. The addition of NADPH–P450 reductase (POR) to an Alexa 488-T70C-b5:P450 17A1 complex resulted in a concentration-dependent partial restoration of b5 fluorescence, indicative of a ternary P450:b5:POR complex, which was also supported by gel filtration experiments. Overall, these results are interpreted in the context of a dynamic and tight P450 17A1:b5 complex that also binds POR to form a catalytically competent ternary complex, and variants that disrupt this interaction have low catalytic activity.
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Affiliation(s)
- Donghak Kim
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, USA; Department of Biological Sciences, Konkuk University, Seoul, Republic of Korea
| | - Vitchan Kim
- Department of Biological Sciences, Konkuk University, Seoul, Republic of Korea
| | - Kevin D McCarty
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
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14
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Abstract
Enzymes are complex biological catalysts and are critical to life. Most oxidations of chemicals are catalyzed by cytochrome P450 (P450, CYP) enzymes, which generally utilize mixed-function oxidase stoichiometry, utilizing pyridine nucleotides as electron donors: NAD(P)H + O2 + R → NAD(P)+ + RO + H2O (where R is a carbon substrate and RO is an oxidized product). The catalysis of oxidations is largely understood in the context of the heme iron-oxygen complex generally referred to as Compound I, formally FeO3+, whose basis was in peroxidase chemistry. Many X-ray crystal structures of P450s are now available (≥ 822 structures from ≥146 different P450s) and have helped in understanding catalytic specificity. In addition to hydroxylations, P450s catalyze more complex oxidations, including C-C bond formation and cleavage. Enzymes derived from P450s by directed evolution can even catalyze more unusual reactions, e.g. cyclopropanation. Current P450 questions under investigation include the potential role of the intermediate Compound 0 (formally FeIII-O2 -) in catalysis of some reactions, the roles of high- and low-spin forms of Compound I, the mechanism of desaturation, the roles of open and closed structures of P450s in catalysis, the extent of processivity in multi-step oxidations, and the role of the accessory protein cytochrome b 5. More global questions include exactly how structure drives function, prediction of catalysis, and roles of multiple protein conformations.
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Affiliation(s)
- F. Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
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15
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Nikulina SY, Shulman VA, Chernova AA, Nikulin DA, Semenchukov AA, Marilovceva OV, Tret'jakova SS, Lebedeva II, Maksimov VN. Role of Single Nucleotide Polymorphism of СУР17А Gene in the Development of Stroke. RATIONAL PHARMACOTHERAPY IN CARDIOLOGY 2018. [DOI: 10.20996/1819-6446-2018-14-4-488-493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Background. The search for genetic predictors of stroke development is actively studied in all developed countries due to the need to address the primary prevention of socially significant diseases. Gene CYP17A1 is one of the many genes that can participate in the formation of predisposition to the development of stroke.Aim. To examine association of the single nucleotide polymorphisms rs1004467 CYP17A1 gene with the development of stroke.Material and methods. The study included 184 patients with stroke (active group; 113 men and 71 women; mean age 55.06±9.40 years), 131 of them with ischemic stroke and 41 with hemorrhagic stroke. The comparison group included 251 people with hypertension without stroke (160 men and 91 women; mean age 59.21±6.62 years) and control group – 157 persons without cardiovascular diseases (106 men and 51 women; mean age 54.94±6.64 years). Study participants underwent clinical (collection of complaints, anamnesis, physical examination), laboratory (blood chemistry, lipid profile) and instrumental (computer tomography of the brain, ultrasound duplex scanning of extraand intracranial blood vessels, electrocardiography, echocardioscopy) examination to verify the diagnosis, molecular genetic study of gene polymorphism СУР17А.Results. The study established the association of homozygous genotype AA rs1004467 CYP17A1 gene with the risk of stroke, which is confirmed bya statistically significant increase in the number of carriers of homozygous genotype AA in the common allele A rs1004467 CYP17A1 gene in patients of the main group (73.4±3.3%) compared to the control group (61.8±3.9%; p=0.03). Statistically significant increase in the number of carriers of genotype AA rs1004467 of CYP17A1 gene in patients with hemorrhagic stroke (70.7±7.1%) compared with the control (61.8±3.9%; p=0.01) was revealed. There are no statistically significant associations between the rs1004467 genotypes of CYP17A1 gene and the risk factors of stroke (hypercholesterinemia, burdened hereditary, hypertension, increased intima-media thickness of brachiocephalic arteries).Conclusions. The ability to consider the genetic determinants of brain stroke allows to identify proactively the risk factors of this complex cascade process. Studies of gene polymorphism as a factor of genetic predisposition to various human diseases allow to determine the individual possibilities of optimal therapy for each patient, considering the identified risk factors.
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16
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Sarathi V, Reddy R, Atluri S, Shivaprasad C. A challenging case of primary amenorrhoea. BMJ Case Rep 2018; 2018:bcr-2018-225447. [PMID: 30002216 DOI: 10.1136/bcr-2018-225447] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
The differential diagnosis of a girl presenting with primary amenorrhoea includes numerous conditions. Often, patients of 46XY disorder of sex development (DSD) are reared as girl and present with primary amenorrhoea. Their further evaluation to reach the final diagnosis is often a great challenge. In this article, we report a challenging case of 46XY DSD presented with primary amenorrhoea. Patient had spontaneous breast development which initially confused the diagnosis to complete androgen insensitivity syndrome. However, low testosterone suggested against this possibility and further evaluation revealed hormonal findings consistent with 17α hydroxylase/17,20 lyase (CYP17A1) deficiency. Patient had 46XY karyotype and in consistence with hormonal findings patient was found to have a likely pathogenic homozygous c.1345C>T (p.Arg449Cys) variation in exon 8 of CYP17A1.
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Affiliation(s)
- Vijaya Sarathi
- Endocrinology, Vydehi Institute of Medical Sciences and Research Centre, Bangalore, Karnataka, India
| | - Ramesh Reddy
- General Surgery, Vydehi Institute of Medical Sciences and Research Centre, Bangalore, Karnataka, India
| | - Sridevi Atluri
- Endocrinology, Vydehi Institute of Medical Sciences and Research Centre, Bangalore, Karnataka, India
| | - Channabasappa Shivaprasad
- Endocrinology, Vydehi Institute of Medical Sciences and Research Centre, Bangalore, Karnataka, India
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17
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Peng HM, Barlow C, Auchus RJ. Catalytic modulation of human cytochromes P450 17A1 and P450 11B2 by phospholipid. J Steroid Biochem Mol Biol 2018; 181:63-72. [PMID: 29548669 PMCID: PMC5992074 DOI: 10.1016/j.jsbmb.2018.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 02/19/2018] [Accepted: 03/08/2018] [Indexed: 10/17/2022]
Abstract
Unlike most of the drug-metabolizing cytochrome P450s, microsomal P450 17A1 and mitochondrial P450 11B2 catalyze sequential multi-step reactions in steroid biosynthesis. The membrane phospholipid composition might be one parameter that modulates the efficiency and processivity of specific pathways. Here we systematically examined the effects of physiologically relevant phospholipids on the catalysis of purified P450 17A1, P450 11B2, and P450 11B1 in reconstituted assay systems. Both dioleoylphosphatidylcholine (DOPC, 18:1) and dilauroylphosphatidylcholine (DLPC, 12:0) were found to be very efficient in reconstituting 17-hydroxylase and 1720-lyase reactions of P450 17A1. Phosphatidylethanolamine (PE) specifically enhanced 1720-lyase activity up to 2.4-fold in the presence of phosphatidylcholine. On the other hand, P450 11B2-catalyzed production of aldosterone from 11-deoxycorticosterone was very low and from 18-hydroxycorticosterone nil, implying low processivity. DOPC or cardiolipin, which is exclusively located in the inner mitochondrial membrane, maximized aldosterone yield. In sharp contrast, reconstitution of homologous P450 11B1 with DOPC significantly decreased corticosterone formation without affecting the synthesis of 18-hydroxycorticosterone. The intrinsic fluorescence of P450 17A1 and 11B2 increased in the presence of DOPC, DLPC and PE. Acrylamide quenching studies showed that PE decreased solvent accessibility for tryptophan in P450 17A1, as did 20:4 PC or 18:2 PC for P450 11B2. A moderately positive correlation between the proportion of high-spin substrate-bound species and catalytic activity was only observed in the presence of phosphatidylcholines with low-temperature phase transition. These results demonstrate the potential for phospholipids to regulate the activity of steroidogenic P450 activities and thereby steroid hormone biosynthetic pathways.
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Affiliation(s)
- Hwei-Ming Peng
- Division of Metabolism, Endocrinology, and Diabetes, Departments of Internal Medicine and Pharmacology, University of Michigan, Ann Arbor, MI, 48109, United States
| | - Chase Barlow
- Division of Metabolism, Endocrinology, and Diabetes, Departments of Internal Medicine and Pharmacology, University of Michigan, Ann Arbor, MI, 48109, United States
| | - Richard J Auchus
- Division of Metabolism, Endocrinology, and Diabetes, Departments of Internal Medicine and Pharmacology, University of Michigan, Ann Arbor, MI, 48109, United States.
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18
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Guengerich FP, Yoshimoto FK. Formation and Cleavage of C-C Bonds by Enzymatic Oxidation-Reduction Reactions. Chem Rev 2018; 118:6573-6655. [PMID: 29932643 DOI: 10.1021/acs.chemrev.8b00031] [Citation(s) in RCA: 154] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Many oxidation-reduction (redox) enzymes, particularly oxygenases, have roles in reactions that make and break C-C bonds. The list includes cytochrome P450 and other heme-based monooxygenases, heme-based dioxygenases, nonheme iron mono- and dioxygenases, flavoproteins, radical S-adenosylmethionine enzymes, copper enzymes, and peroxidases. Reactions involve steroids, intermediary metabolism, secondary natural products, drugs, and industrial and agricultural chemicals. Many C-C bonds are formed via either (i) coupling of diradicals or (ii) generation of unstable products that rearrange. C-C cleavage reactions involve several themes: (i) rearrangement of unstable oxidized products produced by the enzymes, (ii) oxidation and collapse of radicals or cations via rearrangement, (iii) oxygenation to yield products that are readily hydrolyzed by other enzymes, and (iv) activation of O2 in systems in which the binding of a substrate facilitates O2 activation. Many of the enzymes involve metals, but of these, iron is clearly predominant.
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Affiliation(s)
- F Peter Guengerich
- Department of Biochemistry , Vanderbilt University School of Medicine , Nashville , Tennessee 37232-0146 , United States.,Department of Chemistry , University of Texas-San Antonio , San Antonio , Texas 78249-0698 , United States
| | - Francis K Yoshimoto
- Department of Biochemistry , Vanderbilt University School of Medicine , Nashville , Tennessee 37232-0146 , United States.,Department of Chemistry , University of Texas-San Antonio , San Antonio , Texas 78249-0698 , United States
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19
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Gonzalez E, Johnson KM, Pallan PS, Phan TTN, Zhang W, Lei L, Wawrzak Z, Yoshimoto FK, Egli M, Guengerich FP. Inherent steroid 17α,20-lyase activity in defunct cytochrome P450 17A enzymes. J Biol Chem 2017; 293:541-556. [PMID: 29212707 DOI: 10.1074/jbc.ra117.000504] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/11/2017] [Indexed: 01/08/2023] Open
Abstract
Cytochrome P450 (P450) 17A1 catalyzes the oxidations of progesterone and pregnenolone and is the major source of androgens. The enzyme catalyzes both 17α-hydroxylation and a subsequent 17α,20-lyase reaction, and several mechanisms have been proposed for the latter step. Zebrafish P450 17A2 catalyzes only the 17α-hydroxylations. We previously reported high similarity of the crystal structures of zebrafish P450 17A1 and 17A2 and human P450 17A1. Five residues near the heme, which differed, were changed. We also crystallized this five-residue zebrafish P450 17A1 mutant, and the active site still resembled the structure in the other proteins, with some important differences. These P450 17A1 and 17A2 mutants had catalytic profiles more similar to each other than did the wildtype proteins. Docking with these structures can explain several minor products, which require multiple enzyme conformations. The 17α-hydroperoxy (OOH) derivatives of the steroids were used as oxygen surrogates. Human P450 17A1 and zebrafish P450s 17A1 and P450 17A2 readily converted these to the lyase products in the absence of other proteins or cofactors (with catalytically competent kinetics) plus hydroxylated 17α-hydroxysteroids. The 17α-OOH results indicate that a "Compound I" (FeO3+) intermediate is capable of formation and can be used to rationalize the products. We conclude that zebrafish P450 17A2 is capable of lyase activity with the 17α-OOH steroids because it can achieve an appropriate conformation for lyase catalysis in this system that is precluded in the conventional reaction.
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Affiliation(s)
- Eric Gonzalez
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - Kevin M Johnson
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - Pradeep S Pallan
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - Thanh T N Phan
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - Wei Zhang
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - Li Lei
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - Zdzislaw Wawrzak
- the Life Sciences Collaborative Access Team, Sector 21, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, and
| | | | - Martin Egli
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - F Peter Guengerich
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146,
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20
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Lampe JN. Advances in the Understanding of Protein-Protein Interactions in Drug Metabolizing Enzymes through the Use of Biophysical Techniques. Front Pharmacol 2017; 8:521. [PMID: 28848438 PMCID: PMC5550701 DOI: 10.3389/fphar.2017.00521] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Accepted: 07/24/2017] [Indexed: 02/01/2023] Open
Abstract
In recent years, a growing appreciation has developed for the importance of protein-protein interactions to modulate the function of drug metabolizing enzymes. Accompanied with this appreciation, new methods and technologies have been designed for analyzing protein-protein interactions both in vitro and in vivo. These technologies have been applied to several classes of drug metabolizing enzymes, including: cytochrome P450's (CYPs), monoamine oxidases (MAOs), UDP-glucuronosyltransferases (UGTs), glutathione S-transferases (GSTs), and sulfotransferases (SULTs). In this review, we offer a brief description and assessment of the impact of many of these technologies to the study of protein-protein interactions in drug disposition. The still expanding list of these techniques and assays has the potential to revolutionize our understanding of how these enzymes carry out their important functions in vivo.
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Affiliation(s)
- Jed N Lampe
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical CenterKansas City, MO, United States
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21
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Bhatt MR, Khatri Y, Rodgers RJ, Martin LL. Role of cytochrome b5 in the modulation of the enzymatic activities of cytochrome P450 17α-hydroxylase/17,20-lyase (P450 17A1). J Steroid Biochem Mol Biol 2017; 170:2-18. [PMID: 26976652 DOI: 10.1016/j.jsbmb.2016.02.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 02/25/2016] [Accepted: 02/27/2016] [Indexed: 12/13/2022]
Abstract
Cytochrome b5 (cyt b5) is a small hemoprotein that plays a significant role in the modulation of activities of an important steroidogenic enzyme, cytochrome P450 17α-hydroxylase/17,20-lyase (P450 17A1, CYP17A1). Located in the zona fasciculata and zona reticularis of the adrenal cortex and in the gonads, P450 17A1 catalyzes two different reactions in the steroidogenic pathway; the 17α-hydroxylation and 17,20-lyase, in the endoplasmic reticulum of these respective tissues. The activities of P450 17A1 are regulated by cyt b5 that enhances the 17,20-lyase reaction by promoting the coupling of P450 17A1 and cytochrome P450 reductase (CPR), allosterically. Cyt b5 can also act as an electron donor to enhance the 16-ene-synthase activity of human P450 17A1. In this review, we discuss the many roles of cyt b5 and focus on the modulation of CYP17A1 activities by cyt b5 and the mechanisms involved.
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Affiliation(s)
- Megh Raj Bhatt
- Everest Biotech Pvt. Ltd., Khumaltar, Lalitpur, P.O. Box 21608, Kathmandu 44600, Nepal
| | - Yogan Khatri
- Institute of Biochemistry, Saarland University, 66123 Saarbrücken, Germany
| | - Raymond J Rodgers
- School of Medicine, Robinson Research Institute, University of Adelaide, Adelaide SA 5005, Australia
| | - Lisandra L Martin
- School of Chemistry, Monash University, Clayton, 3800, Victoria, Australia.
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22
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Peng HM, Auchus RJ. Molecular Recognition in Mitochondrial Cytochromes P450 That Catalyze the Terminal Steps of Corticosteroid Biosynthesis. Biochemistry 2017; 56:2282-2293. [DOI: 10.1021/acs.biochem.7b00034] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Hwei-Ming Peng
- Division of Metabolism, Endocrinology,
and Diabetes, Department of Internal Medicine, and Department of Pharmacology, University of Michigan Health System, Ann Arbor, Michigan 48109, United States
| | - Richard J. Auchus
- Division of Metabolism, Endocrinology,
and Diabetes, Department of Internal Medicine, and Department of Pharmacology, University of Michigan Health System, Ann Arbor, Michigan 48109, United States
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23
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Auchus RJ. Steroid 17-hydroxylase and 17,20-lyase deficiencies, genetic and pharmacologic. J Steroid Biochem Mol Biol 2017; 165:71-78. [PMID: 26862015 PMCID: PMC4976049 DOI: 10.1016/j.jsbmb.2016.02.002] [Citation(s) in RCA: 123] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 01/22/2016] [Accepted: 02/03/2016] [Indexed: 12/12/2022]
Abstract
Steroid 17-hydroxylase 17,20-lyase (cytochrome P450c17, P450 17A1, CYP17A1) catalyzes two major reactions: steroid 17-hydroxylation followed by the 17,20-lyase reactions. The most severe mutations in the cognate CYP17A1 gene abrogate all activities and cause combined 17-hydroxylase/17,20-lyase deficiency (17OHD), a biochemical phenotype that is replicated by treatment with the potent CYP17A1 inhibitor abiraterone acetate. The adrenals of patients with 17OHD synthesize 11-deoxycorticosterone (DOC) and corticosterone but no 19-carbon steroids, similar to the rodent adrenal, and DOC causes hypertension and hypokalemia. Loss of 17,20-lyase activity precludes sex steroid synthesis and leads to sexual infantilism. Rare missense CYP17A1 mutations minimally disrupt 17-hydroxylase activity but cause isolated 17,20-lyase deficiency (ILD), Mutations in the POR gene encoding the required cofactor protein cytochrome P450-oxidoreductase causes a spectrum of disease from ILD to 17OHD combined with 21-hydroxylase and aromatase deficiencies, sometimes including skeletal malformations. Mutations in the CYB5A gene encoding a second cofactor protein cytochrome b5 also selectively disrupt 17,20-lyase activity and cause the purest form of ILD. The clinical manifestations of these conditions are best understood in the context of the biochemistry of CYP17A1.
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Affiliation(s)
- Richard J Auchus
- Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine and Department of Pharmacology, University of Michigan, Rm. 5560A MSRBII, 1150 W Medical Center Drive, Ann Arbor, MI 48109, United States.
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24
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Bird IM, Abbott DH. The hunt for a selective 17,20 lyase inhibitor; learning lessons from nature. J Steroid Biochem Mol Biol 2016; 163:136-46. [PMID: 27154414 PMCID: PMC5046225 DOI: 10.1016/j.jsbmb.2016.04.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/26/2016] [Accepted: 04/28/2016] [Indexed: 01/10/2023]
Abstract
Given prostate cancer is driven, in part, by its responsiveness to androgens, treatments historically employ methods for their removal from circulation. Approaches as crude as castration, and more recently blockade of androgen synthesis or receptor binding, are still of limited use long term, since other steroids of adrenal origin or tumor origin can supersede that role as the 'castration resistant' tumor re-emerges. Broader inhibition of steroidogenesis using relatively nonselective P450 inhibitors such as ketoconazole is not an alternative since a general disruption of steroid biosynthesis is neither safe nor effective. The recent emergence of drugs more selectively targeting CYP17 have been more effective, and yet extension of life has been on the scale of months rather than years. It is now becoming clear this shortcoming arises from the adaptive capabilities of many tumors to initiate local steroid synthesis and/or become responsive to novel early pathway adrenal steroids that are synthesized when lyase activity is not selectively blocked, and ACTH rises in the face of declining cortisol feedback. Abiraterone has been described as a lyase selective inhibitor, yet its use still requires co-administration of prednisone to suppress such a rise of ACTH and fall in cortisol. So is creation of a selective lyase inhibitor even possible? Can C19 steroid production be achieved without a prominent decline in cortisol and corresponding rise in ACTH? Decades of scientific study of CYP17 in humans and nonhuman primates, as well as nature's own experiments of gene mutations in humans, reveal 'true' or 'isolated' 17,20 lyase deficiency does quite selectively prevent C19 steroid biosynthesis whereas simple 17 hydroxylase deficiency also suppresses cortisol. We propose these known outcomes of natural mutations should be used to guide analysis of clinical trials and long term outcomes of CYP17 targeted drugs. In this review, we use that framework to re-evaluate the basic and clinical outcomes of many compounds being used or in development for treatment of castration resistant prostate cancer. Specifically, we include the nonselective drug ketoconazole, and then the CYP17 targeted drugs abiraterone, orteronel (TAK-700), galaterone (TOK-001), and seviteronel (VT-464). Using this framework, we can fully discriminate the clinical outcomes for ketoconazole, a drug with broad specificity, yet clinically ineffective, from that of abiraterone, the first CYP17 targeted therapy that is limited by its need for prednisone co-therapy. We also can identify potential next generation CYP17 targeted drugs now emerging that show signs of being far more 17,20 lyase selective. We conclude that a future for improved therapy without substantial cortisol decline, thus avoiding prednisone co-administration, seems possible at long last.
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Affiliation(s)
- Ian M Bird
- Department Ob/Gyn, University of Wisconsin-Madison SMPH, Madison, WI, USA.
| | - David H Abbott
- Department Ob/Gyn, University of Wisconsin-Madison SMPH, Madison, WI, USA; Wisconsin National Primate Research Center, University of Wisconsin, Madison, WI, USA
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25
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Peng HM, Im SC, Pearl NM, Turcu AF, Rege J, Waskell L, Auchus RJ. Cytochrome b5 Activates the 17,20-Lyase Activity of Human Cytochrome P450 17A1 by Increasing the Coupling of NADPH Consumption to Androgen Production. Biochemistry 2016; 55:4356-65. [PMID: 27426448 PMCID: PMC5287367 DOI: 10.1021/acs.biochem.6b00532] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Human cytochrome P450 17A1 is required for all androgen biosynthesis and is the target of abiraterone, a drug used widely to treat advanced prostate cancer. P450 17A1 catalyzes both 17-hydroxylation and subsequent 17,20-lyase reactions with pregnenolone, progesterone, and allopregnanolone. The presence of cytochrome b5 (b5) markedly stimulates the 17,20-lyase reaction, with little effect on 17-hydroxylation; however, the mechanism of this b5 effect is not known. We determined the influence of b5 on coupling efficiency-defined as the ratio of product formation to NADPH consumption-in a reconstituted system using these 3 pairs of substrates for the 2 reactions. Rates of NADPH consumption ranged from 4 to 13 nmol/min/nmol P450 with wild-type P450 17A1. For the 17-hydroxylase reaction, progesterone oxidation was the most tightly coupled (∼50%) and negligibly changed upon addition of b5. Rates of NADPH consumption were similar for the 17-hydroxylase and corresponding 17,20-lyase reactions for each steroid series, and b5 only slightly increased NADPH consumption. For the 17,20-lyase reactions, b5 markedly increased product formation and coupling in parallel with all substrates, from 6% to 44% with the major substrate 17-hydroxypregnenolone. For the naturally occurring P450 17A1 mutations E305G and R347H, which impair 17,20-lyase activity, b5 failed to rescue the poor coupling with 17-hydroxypregnenolone (2-4%). When the conserved active-site threonine was mutated to alanine (T306A), both the activity and coupling were markedly decreased with all substrates. We conclude that b5 stimulation of the 17,20-lyase reaction primarily derives from more efficient use of NADPH for product formation rather than side products.
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Affiliation(s)
- Hwei-Ming Peng
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109
| | - Sang-Choul Im
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109
- Department of Anesthesiology, University of Michigan and the VA Medical Center, 2215 Fuller Road, Building 31, Room 225, Ann Arbor, MI 48105, United States
| | - Naw May Pearl
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109
- Department of Anesthesiology, University of Michigan and the VA Medical Center, 2215 Fuller Road, Building 31, Room 225, Ann Arbor, MI 48105, United States
| | - Adina F. Turcu
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109
| | - Juilee Rege
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109
| | - Lucy Waskell
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109
- Department of Anesthesiology, University of Michigan and the VA Medical Center, 2215 Fuller Road, Building 31, Room 225, Ann Arbor, MI 48105, United States
| | - Richard J. Auchus
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109
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26
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Guengerich FP, Waterman MR, Egli M. Recent Structural Insights into Cytochrome P450 Function. Trends Pharmacol Sci 2016; 37:625-640. [PMID: 27267697 PMCID: PMC4961565 DOI: 10.1016/j.tips.2016.05.006] [Citation(s) in RCA: 208] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 05/07/2016] [Accepted: 05/11/2016] [Indexed: 02/08/2023]
Abstract
Cytochrome P450 (P450) enzymes are important in the metabolism of drugs, steroids, fat-soluble vitamins, carcinogens, pesticides, and many other types of chemicals. Their catalytic activities are important issues in areas such as drug-drug interactions and endocrine function. During the past 30 years, structures of P450s have been very helpful in understanding function, particularly the mammalian P450 structures available in the past 15 years. We review recent activity in this area, focusing on the past 2 years (2014-2015). Structural work with microbial P450s includes studies related to the biosynthesis of natural products and the use of parasitic and fungal P450 structures as targets for drug discovery. Studies on mammalian P450s include the utilization of information about 'drug-metabolizing' P450s to improve drug development and also to understand the molecular bases of endocrine dysfunction.
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Affiliation(s)
- F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA.
| | - Michael R Waterman
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA
| | - Martin Egli
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA.
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27
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Jeřábek P, Florián J, Martínek V. Membrane-Anchored Cytochrome P450 1A2–Cytochrome b5 Complex Features an X-Shaped Contact between Antiparallel Transmembrane Helices. Chem Res Toxicol 2016; 29:626-36. [DOI: 10.1021/acs.chemrestox.5b00349] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Petr Jeřábek
- Department
of Biochemistry, Faculty of Science, Charles University in Prague, Albertov 2030, 128 43 Prague 2, Czech Republic
| | - Jan Florián
- Department
of Chemistry and Biochemistry, Loyola University Chicago, 1032 West Sheridan
Road, Chicago, Illinois 60660, United States
| | - Václav Martínek
- Department
of Biochemistry, Faculty of Science, Charles University in Prague, Albertov 2030, 128 43 Prague 2, Czech Republic
- Department of Teaching and Didactics of Chemistry, Faculty of Science, Charles University in Prague, Albertov 3, 128 43 Prague 2, Czech Republic
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28
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Sondhi V, Owen BM, Liu J, Chomic R, Kliewer SA, Hughes BA, Arlt W, Mangelsdorf DJ, Auchus RJ. Impaired 17,20-Lyase Activity in Male Mice Lacking Cytochrome b5 in Leydig Cells. Mol Endocrinol 2016; 30:469-78. [PMID: 26974035 PMCID: PMC4814474 DOI: 10.1210/me.2015-1282] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Androgen and estrogen biosynthesis in mammals requires the 17,20-lyase activity of cytochrome P450 17A1 (steroid 17-hydroxylase/17,20-lyase). Maximal 17,20-lyase activity in vitro requires the presence of cytochrome b5 (b5), and rare cases of b5 deficiency in human beings causes isolated 17,20-lyase deficiency. To study the consequences of conditional b5 removal from testicular Leydig cells in an animal model, we generated Cyb5flox/flox:Sf1-Cre (LeyKO) mice. The LeyKO male mice had normal body weights, testis and sex organ weights, and fertility compared with littermates. Basal serum and urine steroid profiles of LeyKO males were not significantly different than littermates. In contrast, marked 17-hydroxyprogesterone accumulation (100-fold basal) and reduced testosterone synthesis (27% of littermates) were observed after human chorionic gonadotropin stimulation in LeyKO animals. Testis homogenates from LeyKO mice showed reduced 17,20-lyase activity and a 3-fold increased 17-hydroxylase to 17,20-lyase activity ratio, which were restored to normal upon addition of recombinant b5. We conclude that Leydig cell b5 is required for maximal androgen synthesis and to prevent 17-hydroxyprogesterone accumulation in the mouse testis; however, the b5-independent 17,20-lyase activity of mouse steroid 17-hydroxylase/17,20-lyase is sufficient for normal male genital development and fertility. LeyKO male mice are a good model for the biochemistry but not the physiology of isolated 17,20-lyase deficiency in human beings.
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Affiliation(s)
- Varun Sondhi
- Departments of Pharmacology (V.S., B.M.O., S.A.K., D.J.M.) and Molecular Biology (S.A.K.) and the Howard Hughes Medical Institute (D.J.M.), University of Texas Southwestern Medical Center, Dallas, Texas 75390; Departments of Internal Medicine and Pharmacology (J.L., R.J.A.) and the Michigan Metabolomics and Obesity Center (R.C.), University of Michigan, Ann Arbor, Michigan 48109; and the Institute of Metabolism and Systems Research (B.A.H., W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Bryn M Owen
- Departments of Pharmacology (V.S., B.M.O., S.A.K., D.J.M.) and Molecular Biology (S.A.K.) and the Howard Hughes Medical Institute (D.J.M.), University of Texas Southwestern Medical Center, Dallas, Texas 75390; Departments of Internal Medicine and Pharmacology (J.L., R.J.A.) and the Michigan Metabolomics and Obesity Center (R.C.), University of Michigan, Ann Arbor, Michigan 48109; and the Institute of Metabolism and Systems Research (B.A.H., W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Jiayan Liu
- Departments of Pharmacology (V.S., B.M.O., S.A.K., D.J.M.) and Molecular Biology (S.A.K.) and the Howard Hughes Medical Institute (D.J.M.), University of Texas Southwestern Medical Center, Dallas, Texas 75390; Departments of Internal Medicine and Pharmacology (J.L., R.J.A.) and the Michigan Metabolomics and Obesity Center (R.C.), University of Michigan, Ann Arbor, Michigan 48109; and the Institute of Metabolism and Systems Research (B.A.H., W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Robert Chomic
- Departments of Pharmacology (V.S., B.M.O., S.A.K., D.J.M.) and Molecular Biology (S.A.K.) and the Howard Hughes Medical Institute (D.J.M.), University of Texas Southwestern Medical Center, Dallas, Texas 75390; Departments of Internal Medicine and Pharmacology (J.L., R.J.A.) and the Michigan Metabolomics and Obesity Center (R.C.), University of Michigan, Ann Arbor, Michigan 48109; and the Institute of Metabolism and Systems Research (B.A.H., W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Steven A Kliewer
- Departments of Pharmacology (V.S., B.M.O., S.A.K., D.J.M.) and Molecular Biology (S.A.K.) and the Howard Hughes Medical Institute (D.J.M.), University of Texas Southwestern Medical Center, Dallas, Texas 75390; Departments of Internal Medicine and Pharmacology (J.L., R.J.A.) and the Michigan Metabolomics and Obesity Center (R.C.), University of Michigan, Ann Arbor, Michigan 48109; and the Institute of Metabolism and Systems Research (B.A.H., W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Beverly A Hughes
- Departments of Pharmacology (V.S., B.M.O., S.A.K., D.J.M.) and Molecular Biology (S.A.K.) and the Howard Hughes Medical Institute (D.J.M.), University of Texas Southwestern Medical Center, Dallas, Texas 75390; Departments of Internal Medicine and Pharmacology (J.L., R.J.A.) and the Michigan Metabolomics and Obesity Center (R.C.), University of Michigan, Ann Arbor, Michigan 48109; and the Institute of Metabolism and Systems Research (B.A.H., W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Wiebke Arlt
- Departments of Pharmacology (V.S., B.M.O., S.A.K., D.J.M.) and Molecular Biology (S.A.K.) and the Howard Hughes Medical Institute (D.J.M.), University of Texas Southwestern Medical Center, Dallas, Texas 75390; Departments of Internal Medicine and Pharmacology (J.L., R.J.A.) and the Michigan Metabolomics and Obesity Center (R.C.), University of Michigan, Ann Arbor, Michigan 48109; and the Institute of Metabolism and Systems Research (B.A.H., W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - David J Mangelsdorf
- Departments of Pharmacology (V.S., B.M.O., S.A.K., D.J.M.) and Molecular Biology (S.A.K.) and the Howard Hughes Medical Institute (D.J.M.), University of Texas Southwestern Medical Center, Dallas, Texas 75390; Departments of Internal Medicine and Pharmacology (J.L., R.J.A.) and the Michigan Metabolomics and Obesity Center (R.C.), University of Michigan, Ann Arbor, Michigan 48109; and the Institute of Metabolism and Systems Research (B.A.H., W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Richard J Auchus
- Departments of Pharmacology (V.S., B.M.O., S.A.K., D.J.M.) and Molecular Biology (S.A.K.) and the Howard Hughes Medical Institute (D.J.M.), University of Texas Southwestern Medical Center, Dallas, Texas 75390; Departments of Internal Medicine and Pharmacology (J.L., R.J.A.) and the Michigan Metabolomics and Obesity Center (R.C.), University of Michigan, Ann Arbor, Michigan 48109; and the Institute of Metabolism and Systems Research (B.A.H., W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom
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29
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Simonov AN, Holien JK, Yeung JCI, Nguyen AD, Corbin CJ, Zheng J, Kuznetsov VL, Auchus RJ, Conley AJ, Bond AM, Parker MW, Rodgers RJ, Martin LL. Mechanistic Scrutiny Identifies a Kinetic Role for Cytochrome b5 Regulation of Human Cytochrome P450c17 (CYP17A1, P450 17A1). PLoS One 2015; 10:e0141252. [PMID: 26587646 PMCID: PMC4654539 DOI: 10.1371/journal.pone.0141252] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 10/06/2015] [Indexed: 01/12/2023] Open
Abstract
Cytochrome P450c17 (P450 17A1, CYP17A1) is a critical enzyme in the synthesis of androgens and is now a target enzyme for the treatment of prostate cancer. Cytochrome P450c17 can exhibit either one or two physiological enzymatic activities differentially regulated by cytochrome b5. How this is achieved remains unknown. Here, comprehensive in silico, in vivo and in vitro analyses were undertaken. Fluorescence Resonance Energy Transfer analysis showed close interactions within living cells between cytochrome P450c17 and cytochrome b5. In silico modeling identified the sites of interaction and confirmed that E48 and E49 residues in cytochrome b5 are essential for activity. Quartz crystal microbalance studies identified specific protein-protein interactions in a lipid membrane. Voltammetric analysis revealed that the wild type cytochrome b5, but not a mutated, E48G/E49G cyt b5, altered the kinetics of electron transfer between the electrode and the P450c17. We conclude that cytochrome b5 can influence the electronic conductivity of cytochrome P450c17 via allosteric, protein-protein interactions.
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Affiliation(s)
| | - Jessica K. Holien
- ACRF Rational Drug Discovery Centre, St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | | | - Ann D. Nguyen
- School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - C. Jo Corbin
- School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Jie Zheng
- Department of Physiology and Membrane Biology, School of Medicine, University of California Davis, Davis, California, United States of America
| | | | - Richard J. Auchus
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Alan J. Conley
- School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Alan M. Bond
- School of Chemistry, Monash University, Clayton, Victoria, Australia
| | - Michael W. Parker
- ACRF Rational Drug Discovery Centre, St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Raymond J. Rodgers
- Discipline of Obstetrics and Gynaecology, School of Paediatrics and Reproductive Health, Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
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30
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Storbeck KH, Swart AC, Fox CL, Swart P. Cytochrome b5 modulates multiple reactions in steroidogenesis by diverse mechanisms. J Steroid Biochem Mol Biol 2015; 151:66-73. [PMID: 25446886 DOI: 10.1016/j.jsbmb.2014.11.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 11/02/2014] [Accepted: 11/21/2014] [Indexed: 12/18/2022]
Abstract
Cytochrome b5 (cyt-b5) is a relatively small haemoprotein which plays an important role in the regulation of mammalian steroidogenesis. This unique protein has the ability to modulate the activity of key steroidogenic enzymes via a number of diverse reaction mechanisms. Cyt-b5 can augment the 17,20-lyase activity of CYP17A1 by promoting the interaction of CYP17A1 and POR; enhance the 16-ene-synthase activity of CYP17A1 by acting as an electron donor; and enhance the activity of 3βHSD by increasing the affinity of 3βHSD for its cofactor NAD(+). We review the modulation of CYP17A1 and 3βHSD activity by cyt-b5 and discuss the reaction mechanisms associated with each activity. The physiological importance of cyt-b5 in regulating mammalian steroidogenesis is presented and the impact of inactivating cyt-b5 mutations are reviewed. This article is part of a Special Issue entitled 'Steroid/Sterol signaling'.
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Affiliation(s)
- Karl-Heinz Storbeck
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7600, South Africa
| | - Amanda C Swart
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7600, South Africa
| | - Cheryl L Fox
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7600, South Africa
| | - Pieter Swart
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7600, South Africa.
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31
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Zhang H, Gao N, Liu T, Fang Y, Qi B, Wen Q, Zhou J, Jia L, Qiao H. Effect of Cytochrome b5 Content on the Activity of Polymorphic CYP1A2, 2B6, and 2E1 in Human Liver Microsomes. PLoS One 2015; 10:e0128547. [PMID: 26046844 PMCID: PMC4457846 DOI: 10.1371/journal.pone.0128547] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 04/28/2015] [Indexed: 11/18/2022] Open
Abstract
Human cytochrome b5 (Cyt b5) plays important roles in cytochrome P450 (CYP)-mediated drug metabolism. However, the expression level of Cyt b5 in normal human liver remains largely unknown. The effect of Cyt b5 on overall CYP activity in human liver microsomes (HLM) has rarely been reported and the relationship between Cyt b5 and the activity of polymorphic CYP has not been systematically investigated. In this study, we found that the median value of Cyt b5 protein was 270.01 pmol/mg from 123 HLM samples, and 12- and 19-fold individual variation was observed in Cyt b5 mRNA and protein levels, respectively. Gender and smoking clearly influenced Cyt b5 content. In addition, we found that Cyt b5 protein levels significantly correlated with the overall activity of CYP1A2, 2B6, and 2E1 in HLM. However, when the CYP activities were sorted by single nucleotide polymorphisms (SNP), the effect of Cyt b5 protein on the kinetic parameters varied greatly. There were significant correlations between Cyt b5 content and Vmax and CLint of CYP1A2 wild-types (3860GG, 2159GG, and 5347CC) as well as homozygous mutants (163AA and 3113GG). In contrast to Vmax and CLint, the Km of CYP2B6 516GG and 785AA genotypes was inversely associated with Cyt b5 content. Correlations between Cyt b5 content and Vmax and CLint of CYP2E1 -1293GG, -1293GC, 7632TT, 7632TA, -333TT, and -352AA genotypes were also observed. In conclusion, Cyt b5 expression levels varied considerably in the Chinese cohort from this study. Cyt b5 had significant impact on the overall activity of CYP1A2, 2B6, and 2E1 in HLM and the effects of Cyt b5 protein on polymorphic CYP1A2, 2B6, and 2E1 activity were SNP-dependent. These findings suggest that Cyt b5 plays an important role in CYP-mediated activities in HLM and may possibly be a contributing factor for the individual variation observed in CYP enzyme activities.
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Affiliation(s)
- Haifeng Zhang
- Institute of Clinical Pharmacology, Zhengzhou University, Zhengzhou, China
| | - Na Gao
- Institute of Clinical Pharmacology, Zhengzhou University, Zhengzhou, China
| | - Tingting Liu
- Institute of Clinical Pharmacology, Zhengzhou University, Zhengzhou, China
| | - Yan Fang
- Institute of Clinical Pharmacology, Zhengzhou University, Zhengzhou, China
| | - Bing Qi
- Institute of Clinical Pharmacology, Zhengzhou University, Zhengzhou, China
| | - Qiang Wen
- Institute of Clinical Pharmacology, Zhengzhou University, Zhengzhou, China
| | - Jun Zhou
- Institute of Clinical Pharmacology, Zhengzhou University, Zhengzhou, China
| | - Linjing Jia
- Institute of Clinical Pharmacology, Zhengzhou University, Zhengzhou, China
| | - Hailing Qiao
- Institute of Clinical Pharmacology, Zhengzhou University, Zhengzhou, China
- * E-mail:
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32
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Turcu AF, Rege J, Chomic R, Liu J, Nishimoto HK, Else T, Moraitis AG, Palapattu GS, Rainey WE, Auchus RJ. Profiles of 21-Carbon Steroids in 21-hydroxylase Deficiency. J Clin Endocrinol Metab 2015; 100:2283-90. [PMID: 25850025 PMCID: PMC4454804 DOI: 10.1210/jc.2015-1023] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Marked elevations of 17-hydroxyprogesterone (17OHP) are characteristic of classic 21-hydroxylase deficiency (21OHD). Testing of 17OHP provides the basis for 21OHD diagnosis, although it suffers from several pitfalls. False-positive or false-negative results and poor discrimination of nonclassic 21OHD from carriers limit the utility of serum 17OHP and necessitate dynamic testing after cosyntropin stimulation when values are indeterminate. OBJECTIVE The objective was to provide a detailed characterization of 21-carbon (C21) steroids in classic 21OHD, which might identify other candidate steroids that could be employed for the diagnosis of 21OHD. SETTING AND PARTICIPANTS Patients (11 women, 10 men) with classic 21OHD and 21 sex- and age-matched controls seen in a tertiary referral center were studied. METHODS C21 steroids in the peripheral sera from all subjects, as well as in media from cultured testicular adrenal rest tumor (TART) cells and normal adrenal (NA) cells, were analyzed using liquid chromatography/tandem mass spectrometry (10 steroids). Additionally, the dynamics of C21 steroid metabolism in TART and NA cells were assessed with radiotracer studies. RESULTS Five C21 steroids were significantly higher in 21OHD patients: 17OHP (67-fold; P < .01), 21-deoxycortisol (21dF; 35-fold; P < .01), 16α-hydroxyprogesterone (16OHP; 28-fold; P < .01), progesterone (2-fold; P < .01), and 11β-hydroxyprogesterone (11OHP; not detected in controls; P < .01). The same steroids were the highest in media from TART cells relative to the NA cells: 11OHP, 58- to 65-fold; 21dF, 30- to 41-fold; 17OHP, 9-fold; progesterone, 9- to 12-fold; and 16OHP, 7-fold. CONCLUSION Measurement of 16OHP and 11OHP along with 17OHP and 21dF by liquid chromatography/tandem mass spectrometry might comprise a biomarker panel to accurately diagnose all forms of 21OHD.
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Affiliation(s)
- Adina F Turcu
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
| | - Juilee Rege
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
| | - Robert Chomic
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
| | - Jiayan Liu
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
| | - Hiromi K Nishimoto
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
| | - Tobias Else
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
| | - Andreas G Moraitis
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
| | - Ganesh S Palapattu
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
| | - William E Rainey
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
| | - Richard J Auchus
- Division of Metabolism, Endocrinology, and Diabetes (A.F.T., J.L., T.E., A.G.M., W.E.R., R.J.A.), Department of Molecular and Integrative Physiology and Medicine (J.R., H.K.N., W.E.R.), Michigan Metabolomics and Obesity Center (R.C.), Department of Urology (G.S.P.), and Department of Pharmacology (R.J.A.), University of Michigan, Ann Arbor, Michigan 48109
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Pallan PS, Nagy LD, Lei L, Gonzalez E, Kramlinger VM, Azumaya CM, Wawrzak Z, Waterman MR, Guengerich FP, Egli M. Structural and kinetic basis of steroid 17α,20-lyase activity in teleost fish cytochrome P450 17A1 and its absence in cytochrome P450 17A2. J Biol Chem 2014; 290:3248-68. [PMID: 25533464 DOI: 10.1074/jbc.m114.627265] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cytochrome P450 (P450) 17A enzymes play a critical role in the oxidation of the steroids progesterone (Prog) and pregnenolone (Preg) to glucocorticoids and androgens. In mammals, a single enzyme, P450 17A1, catalyzes both 17α-hydroxylation and a subsequent 17α,20-lyase reaction with both Prog and Preg. Teleost fish contain two 17A P450s; zebrafish P450 17A1 catalyzes both 17α-hydroxylation and lyase reactions with Prog and Preg, and P450 17A2 is more efficient in pregnenolone 17α-hydroxylation but does not catalyze the lyase reaction, even in the presence of cytochrome b5. P450 17A2 binds all substrates and products, although more loosely than P450 17A1. Pulse-chase and kinetic spectral experiments and modeling established that the two-step P450 17A1 Prog oxidation is more distributive than the Preg reaction, i.e. 17α-OH product dissociates more prior to the lyase step. The drug orteronel selectively blocked the lyase reaction of P450 17A1 but only in the case of Prog. X-ray crystal structures of zebrafish P450 17A1 and 17A2 were obtained with the ligand abiraterone and with Prog for P450 17A2. Comparison of the two fish P450 17A-abiraterone structures with human P450 17A1 (DeVore, N. M., and Scott, E. E. (2013) Nature 482, 116-119) showed only a few differences near the active site, despite only ∼50% identity among the three proteins. The P450 17A2 structure differed in four residues near the heme periphery. These residues may allow the proposed alternative ferric peroxide mechanism for the lyase reaction, or residues removed from the active site may allow conformations that lead to the lyase activity.
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Affiliation(s)
- Pradeep S Pallan
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 and
| | - Leslie D Nagy
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 and
| | - Li Lei
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 and
| | - Eric Gonzalez
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 and
| | - Valerie M Kramlinger
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 and
| | - Caleigh M Azumaya
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 and
| | - Zdzislaw Wawrzak
- the Life Sciences Collaborative Access Team, Sector 21, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439
| | - Michael R Waterman
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 and
| | - F Peter Guengerich
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 and
| | - Martin Egli
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 and
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