1
|
Ding K, Liu C, Li L, Yang M, Jiang N, Luo S, Sun L. Acyl-CoA synthase ACSL4: an essential target in ferroptosis and fatty acid metabolism. Chin Med J (Engl) 2023; 136:2521-2537. [PMID: 37442770 PMCID: PMC10617883 DOI: 10.1097/cm9.0000000000002533] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Indexed: 07/15/2023] Open
Abstract
ABSTRACT Long-chain acyl-coenzyme A (CoA) synthase 4 (ACSL4) is an enzyme that esterifies CoA into specific polyunsaturated fatty acids, such as arachidonic acid and adrenic acid. Based on accumulated evidence, the ACSL4-catalyzed biosynthesis of arachidonoyl-CoA contributes to the execution of ferroptosis by triggering phospholipid peroxidation. Ferroptosis is a type of programmed cell death caused by iron-dependent peroxidation of lipids; ACSL4 and glutathione peroxidase 4 positively and negatively regulate ferroptosis, respectively. In addition, ACSL4 is an essential regulator of fatty acid (FA) metabolism. ACSL4 remodels the phospholipid composition of cell membranes, regulates steroidogenesis, and balances eicosanoid biosynthesis. In addition, ACSL4-mediated metabolic reprogramming and antitumor immunity have attracted much attention in cancer biology. Because it facilitates the cross-talk between ferroptosis and FA metabolism, ACSL4 is also a research hotspot in metabolic diseases and ischemia/reperfusion injuries. In this review, we focus on the structure, biological function, and unique role of ASCL4 in various human diseases. Finally, we propose that ACSL4 might be a potential therapeutic target.
Collapse
Affiliation(s)
- Kaiyue Ding
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Chongbin Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Li Li
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Ming Yang
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Na Jiang
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Shilu Luo
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Lin Sun
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| |
Collapse
|
2
|
Miller JC, Lee JHZ, Mclean MA, Chao RR, Stone ISJ, Pukala TL, Bruning JB, De Voss JJ, Schuler MA, Sligar SG, Bell SG. Engineering C-C Bond Cleavage Activity into a P450 Monooxygenase Enzyme. J Am Chem Soc 2023; 145:9207-9222. [PMID: 37042073 PMCID: PMC10795798 DOI: 10.1021/jacs.3c01456] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
The cytochrome P450 (CYP) superfamily of heme monooxygenases has demonstrated ability to facilitate hydroxylation, desaturation, sulfoxidation, epoxidation, heteroatom dealkylation, and carbon-carbon bond formation and cleavage (lyase) reactions. Seeking to study the carbon-carbon cleavage reaction of α-hydroxy ketones in mechanistic detail using a microbial P450, we synthesized α-hydroxy ketone probes based on the physiological substrate for a well-characterized benzoic acid metabolizing P450, CYP199A4. After observing low activity with wild-type CYP199A4, subsequent assays with an F182L mutant demonstrated enzyme-dependent C-C bond cleavage toward one of the α-hydroxy ketones. This C-C cleavage reaction was subject to an inverse kinetic solvent isotope effect analogous to that observed in the lyase activity of the human P450 CYP17A1, suggesting the involvement of a species earlier than Compound I in the catalytic cycle. Co-crystallization of F182L-CYP199A4 with this α-hydroxy ketone showed that the substrate bound in the active site with a preference for the (S)-enantiomer in a position which could mimic the topology of the lyase reaction in CYP17A1. Molecular dynamics simulations with an oxy-ferrous model of CYP199A4 revealed a displacement of the substrate to allow for oxygen binding and the formation of the lyase transition state proposed for CYP17A1. This demonstration that a correctly positioned α-hydroxy ketone substrate can realize lyase activity with an unusual inverse solvent isotope effect in an engineered microbial system opens the door for further detailed biophysical and structural characterization of CYP catalytic intermediates.
Collapse
Affiliation(s)
- Justin C Miller
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Joel H Z Lee
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Mark A Mclean
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Rebecca R Chao
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Isobella S J Stone
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Tara L Pukala
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - John B Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - James J De Voss
- School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, Queensland 4072, Australia
| | - Mary A Schuler
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Stephen G Sligar
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Stephen G Bell
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| |
Collapse
|
3
|
Abstract
The adrenal gland is a source of sex steroid precursors, and its activity is particularly relevant during fetal development and adrenarche. Following puberty, the synthesis of androgens by the adrenal gland has been considered of little physiologic importance. Dehydroepiandrosterone (DHEA) and its sulfate, DHEAS, are the major adrenal androgen precursors, but they are biologically inactive. The second most abundant unconjugated androgen produced by the human adrenals is 11β-hydroxyandrostenedione (11OHA4). 11-Ketotestosterone, a downstream metabolite of 11OHA4 (which is mostly produced in peripheral tissues), and its 5α-reduced product, 11-ketodihydrotestosterone, are bioactive androgens, with potencies equivalent to those of testosterone and dihydrotestosterone. These adrenal-derived androgens all share an oxygen atom on carbon 11, so we have collectively termed them 11-oxyandrogens. Over the past decade, these androgens have emerged as major components of several disorders of androgen excess, such as congenital adrenal hyperplasia, premature adrenarche and polycystic ovary syndrome, as well as in androgen-dependent tumours, such as castration-resistant prostate cancer. Moreover, in contrast to the more extensively studied, traditional androgens, circulating concentrations of 11-oxyandrogens do not demonstrate an age-dependent decline. This Review focuses on the rapidly expanding knowledge regarding the implications of 11-oxyandrogens in human physiology and disease.
Collapse
Affiliation(s)
- Adina F Turcu
- Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, MI, USA.
| | - Juilee Rege
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Richard J Auchus
- Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, MI, USA
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
| | - William E Rainey
- Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, MI, USA
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
4
|
Hu Y, Xiao Y, Rao Z, Kumar V, Liu H, Lu C. Carbon-carbon Bond Cleavage Catalyzed by Human Cytochrome P450 Enzymes: α-ketol as the Key Intermediate Metabolite in Sequential Metabolism of Olanexidine. Drug Metab Lett 2019; 14:41-53. [PMID: 31763971 DOI: 10.2174/1872312813666191125095818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/29/2019] [Accepted: 10/29/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Carbon-carbon bond cleavage of a saturated aliphatic moiety is rarely seen in xenobiotic metabolism. Olanexidine (Olanedine®), containing an n-octyl (C8) side chain, was mainly metabolized to various shortened side chain (C4 to C6) acid-containing metabolites in vivo in preclinical species. In liver microsomes and S9, the major metabolites of olanexidine were from multi-oxidation on its n-octyl (C8) side chain. However, the carbon-carbon bond cleavage mechanism of n-octyl (C8) side chain, and enzyme(s) responsible for its metabolism in human remained unknown. METHODS A pair of regioisomers of α-ketol-containing C8 side chain olanexidine analogs (3,2-ketol olanexidine and 2,3-ketol olanexidine) were synthesized, followed by incubation in human liver microsomes, recombinant human cytochrome P450 enzymes or human hepatocytes, and subsequent metabolite identification using LC/UV/MS. RESULTS Multiple shortened side chain (C4 to C6) metabolites were identified, including C4, C5 and C6- acid and C6-hydroxyl metabolites. Among 19 cytochrome P450 enzymes tested, CYP2D6, CYP3A4 and CYP3A5 were identified to catalyze carbon-carbon bond cleavage. CONCLUSION 3,2-ketol olanexidine and 2,3-ketol olanexidine were confirmed as the key intermediates in carbon-carbon bond cleavage. Its mechanism is proposed that a nucleophilic addition of iron-peroxo species, generated by CYP2D6 and CYP3A4/5, to the carbonyl group caused the carbon-carbon bond cleavage between the adjacent hydroxyl and ketone groups. As results, 2,3-ketol olanexidine formed a C6 side chain acid metabolite. While, 3,2-ketol olanexidine formed a C6 side chain aldehyde intermediate, which was either oxidized to a C6 side chain acid metabolite or reduced to a C6 side chain hydroxyl metabolite.
Collapse
Affiliation(s)
- Yiding Hu
- Drug Metabolism and Pharmacokinetics, Sanofi, Waltham, Massachusetts-MA-02451, United States
| | - Yi Xiao
- Department of Pathology and Laboratory Medicine, Children's Hospital, Los Angeles, California-CA 90027, United States
| | - Zhesui Rao
- Drug Metabolism and Pharmacokinetics, Sanofi, Waltham, Massachusetts-MA-02451, United States
| | - Vasant Kumar
- Analytical R&D, Sanofi, Waltham, Massachusetts-MA-02451, United States
| | - Hanlan Liu
- Department of DMPK and Preformulation, KSQ, Cambridge, Massachusetts- MA 02139, United States
| | - Chuang Lu
- Drug Metabolism and Pharmacokinetics, Sanofi, Waltham, Massachusetts-MA-02451, United States
| |
Collapse
|
5
|
Takeo E, Sugiura Y, Uemura T, Nishimoto K, Yasuda M, Sugiyama E, Ohtsuki S, Higashi T, Nishikawa T, Suematsu M, Fukusaki E, Shimma S. Tandem Mass Spectrometry Imaging Reveals Distinct Accumulation Patterns of Steroid Structural Isomers in Human Adrenal Glands. Anal Chem 2019; 91:8918-8925. [PMID: 31204806 DOI: 10.1021/acs.analchem.9b00619] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Visualizing tissue distribution of steroid hormones is a promising application of MALDI mass spectrometry imaging (MSI). On-tissue chemical derivatization using Girard's T reagent has enhanced the ionization efficiency of steroids. However, discriminating between structural isomers with distinct bioactivities remains a challenge. Herein, we used ion trap MS/tandem MS (MS3) to distinguish a mineralcorticoid aldosterone (Aldo) and a glucocorticoid cortisol (F), from their structural isomers. Our method is also useful to detect hybrid steroids (18-hydroxycortisol [18-OHF] and 18-oxocortisol) with sufficient signal-to-noise ratio. The clinical applicability of the tandem MS method was evaluated by analyzing F, Aldo, and 18-OHF distributions in human adrenal glands. In such clinical specimens, small Aldo-producing cell clusters (APCCs) were identified and were first found to produce a high level of Aldo and not to contain F. Moreover, a part of APCCs produced 18-OHF, presumably converted from F by APCC-specific CYP11B2 activity. Catecholamine species were also visualized with another derivatization reagent (TAHS), and those profiling successfully discriminated pheochromocytoma species. These tandem MSI-methods, coupled with on-tissue chemical derivatization has proven to be useful for detecting low-abundance steroids, including Aldo and hybrid steroids and thus identifying steroid hormone-producing lesions.
Collapse
Affiliation(s)
- Emi Takeo
- Department of Biotechnology, Graduate School of Engineering , Osaka University , 2-1 Yamadaoka , Suita , Osaka 565-0871 , Japan
| | - Yuki Sugiura
- Department of Biochemistry , Keio University School of Medicine , 35 Shinanomachi , Shinjuku-ku, Tokyo 160-8582 , Japan
| | - Tatsuki Uemura
- Department of Pharmaceutical Microbiology, Faculty of Life Sciences , Kumamoto University , 5-1 Oe-honmachi , Chuo-ku, Kumamoto 862-0973 , Japan
| | - Koshiro Nishimoto
- Department of Biochemistry , Keio University School of Medicine , 35 Shinanomachi , Shinjuku-ku, Tokyo 160-8582 , Japan.,Department of Uro-Oncology , Saitama Medical University International Medical Center , 1397-1 Yamane , Hidaka , Saitama 350-1298 , Japan
| | - Masanori Yasuda
- Department of Pathology , Saitama Medical University International Medical Center , 1397-1 Yamane , Hidaka , Saitama 350-1298 , Japan
| | - Eiji Sugiyama
- Department of Biochemistry , Keio University School of Medicine , 35 Shinanomachi , Shinjuku-ku, Tokyo 160-8582 , Japan
| | - Sumio Ohtsuki
- Department of Pharmaceutical Microbiology, Faculty of Life Sciences , Kumamoto University , 5-1 Oe-honmachi , Chuo-ku, Kumamoto 862-0973 , Japan
| | - Tatsuya Higashi
- Faculty of Pharmaceutical Sciences , Tokyo University of Science , 2641 Yamazaki , Noda , Chiba 278-8510 , Japan
| | - Tetsuo Nishikawa
- Endocrinology and Diabetes Center , Yokohama Rosai Hospital , 3211 Kozukuecho , Kohoku-ku, Yokohama , Kanagawa 222-0036 , Japan
| | - Makoto Suematsu
- Department of Biochemistry , Keio University School of Medicine , 35 Shinanomachi , Shinjuku-ku, Tokyo 160-8582 , Japan
| | - Eiichiro Fukusaki
- Department of Biotechnology, Graduate School of Engineering , Osaka University , 2-1 Yamadaoka , Suita , Osaka 565-0871 , Japan
| | - Shuichi Shimma
- Department of Biotechnology, Graduate School of Engineering , Osaka University , 2-1 Yamadaoka , Suita , Osaka 565-0871 , Japan
| |
Collapse
|
6
|
Stowasser M, Gordon RD. Primary Aldosteronism: Changing Definitions and New Concepts of Physiology and Pathophysiology Both Inside and Outside the Kidney. Physiol Rev 2016; 96:1327-84. [DOI: 10.1152/physrev.00026.2015] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In the 60 years that have passed since the discovery of the mineralocorticoid hormone aldosterone, much has been learned about its synthesis (both adrenal and extra-adrenal), regulation (by renin-angiotensin II, potassium, adrenocorticotrophin, and other factors), and effects (on both epithelial and nonepithelial tissues). Once thought to be rare, primary aldosteronism (PA, in which aldosterone secretion by the adrenal is excessive and autonomous of its principal regulator, angiotensin II) is now known to be the most common specifically treatable and potentially curable form of hypertension, with most patients lacking the clinical feature of hypokalemia, the presence of which was previously considered to be necessary to warrant further efforts towards confirming a diagnosis of PA. This, and the appreciation that aldosterone excess leads to adverse cardiovascular, renal, central nervous, and psychological effects, that are at least partly independent of its effects on blood pressure, have had a profound influence on raising clinical and research interest in PA. Such research on patients with PA has, in turn, furthered knowledge regarding aldosterone synthesis, regulation, and effects. This review summarizes current progress in our understanding of the physiology of aldosterone, and towards defining the causes (including genetic bases), epidemiology, outcomes, and clinical approaches to diagnostic workup (including screening, diagnostic confirmation, and subtype differentiation) and treatment of PA.
Collapse
Affiliation(s)
- Michael Stowasser
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - Richard D. Gordon
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| |
Collapse
|
7
|
Midzak A, Papadopoulos V. Adrenal Mitochondria and Steroidogenesis: From Individual Proteins to Functional Protein Assemblies. Front Endocrinol (Lausanne) 2016; 7:106. [PMID: 27524977 PMCID: PMC4965458 DOI: 10.3389/fendo.2016.00106] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 07/18/2016] [Indexed: 12/13/2022] Open
Abstract
The adrenal cortex is critical for physiological function as the central site of glucocorticoid and mineralocorticoid synthesis. It possesses a great degree of specialized compartmentalization at multiple hierarchical levels, ranging from the tissue down to the molecular levels. In this paper, we discuss this functionalization, beginning with the tissue zonation of the adrenal cortex and how this impacts steroidogenic output. We then discuss the cellular biology of steroidogenesis, placing special emphasis on the mitochondria. Mitochondria are classically known as the "powerhouses of the cell" for their central role in respiratory adenosine triphosphate synthesis, and attention is given to mitochondrial electron transport, in both the context of mitochondrial respiration and mitochondrial steroid metabolism. Building on work demonstrating functional assembly of large protein complexes in respiration, we further review research demonstrating a role for multimeric protein complexes in mitochondrial cholesterol transport, steroidogenesis, and mitochondria-endoplasmic reticulum contact. We aim to highlight with this review the shift in steroidogenic cell biology from a focus on the actions of individual proteins in isolation to the actions of protein assemblies working together to execute cellular functions.
Collapse
Affiliation(s)
- Andrew Midzak
- Research Institute of the McGill University, Montreal, QC, Canada
- *Correspondence: Andrew Midzak, ; Vassilios Papadopoulos,
| | - Vassilios Papadopoulos
- Research Institute of the McGill University, Montreal, QC, Canada
- Department of Biochemistry, McGill University, Montreal, QC, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
- *Correspondence: Andrew Midzak, ; Vassilios Papadopoulos,
| |
Collapse
|
8
|
Turcu A, Smith JM, Auchus R, Rainey WE. Adrenal androgens and androgen precursors-definition, synthesis, regulation and physiologic actions. Compr Physiol 2014; 4:1369-81. [PMID: 25428847 PMCID: PMC4437668 DOI: 10.1002/cphy.c140006] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The human adrenal produces more 19 carbon (C19) steroids, by mass, than either glucocorticoids or mineralocorticoids. However, the mechanisms regulating adrenal C19 steroid biosynthesis continue to represent one of the most intriguing mysteries of endocrine physiology. This review will discuss the C19 steroids synthesized by the human adrenal and the features within the adrenal that allow production of these steroids. Finally, we consider the effects of these steroids in normal physiology and disorders of adrenal C19 steroid excess.
Collapse
Affiliation(s)
- Adina Turcu
- Department of Internal Medicine, Division of Metabolism Endocrinology and Diabetes, University of Michigan, Ann Arbor, Michigan; Department of Pediatrics, Division of Pediatric Endocrinology, University of Texas Southwestern Medical Center, Texas; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | | | | | | |
Collapse
|
9
|
Habe T, Mikio S, Umezawa T, Higuchi T. Evidence for Deuterium Retention in the Products after Enzymatic C-C and Ether Bond Cleavages of Deuterated Lignin Model Compounds. ACTA ACUST UNITED AC 2014. [DOI: 10.1080/00021369.1985.10867288] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Tsuyostri Habe
- Research Section of Lignin Chemistry,, Wood Research Institute, Kyoto University, Uji, Kyoto 611, Japan
| | - Shimada Mikio
- Research Section of Lignin Chemistry,, Wood Research Institute, Kyoto University, Uji, Kyoto 611, Japan
| | - Toshiaki Umezawa
- Research Section of Lignin Chemistry,, Wood Research Institute, Kyoto University, Uji, Kyoto 611, Japan
| | - Takayoshi Higuchi
- Research Section of Lignin Chemistry,, Wood Research Institute, Kyoto University, Uji, Kyoto 611, Japan
| |
Collapse
|
10
|
Ivanov YD, Frantsuzov PA, Zöllner A, Medvedeva NV, Archakov AI, Reinle W, Bernhardt R. Atomic Force Microscopy Study of Protein-Protein Interactions in the Cytochrome CYP11A1 (P450scc)-Containing Steroid Hydroxylase System. NANOSCALE RESEARCH LETTERS 2011; 6:54. [PMID: 27502676 PMCID: PMC3212078 DOI: 10.1007/s11671-010-9809-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Accepted: 09/15/2010] [Indexed: 05/31/2023]
Abstract
Atomic force microscopy (AFM) and photon correlation spectroscopy (PCS) were used for monitoring of the procedure for cytochrome CYP11A1 monomerization in solution without phospholipids. It was shown that the incubation of 100 μM CYP11A1 with 12% Emulgen 913 in 50 mM KP, pH 7.4, for 10 min at T = 22°C leads to dissociation of hemoprotein aggregates to monomers with the monomerization degree of (82 ± 4)%. Following the monomerization procedure, CYP11A1 remained functionally active. AFM was employed to detect and visualize the isolated proteins as well as complexes formed between the components of the cytochrome CYP11A1-dependent steroid hydroxylase system. Both Ad and AdR were present in solution as monomers. The typical heights of the monomeric AdR, Ad and CYP11A1 images were measured by AFM and were found to correspond to the sizes 1.6 ± 0.2 nm, 1.0 ± 0.2 nm and 1.8 ± 0.2 nm, respectively. The binary Ad/AdR and AdR/CYP11A1mon complexes with the heights 2.2 ± 0.2 nm and 2.8 ± 0.2 nm, respectively, were registered by use of AFM. The Ad/CYP11A1mon complex formation reaction was kinetically characterized based on optical biosensor data. In addition, the ternary AdR/Ad/CYP11A1 complexes with a typical height of 4 ± 1 nm were AFM registered.
Collapse
Affiliation(s)
- Y D Ivanov
- Institute of Biomedical Chemistry RAMS, Pogodinskaya st. 10, 119121, Moscow, Russia.
| | - P A Frantsuzov
- Institute of Biomedical Chemistry RAMS, Pogodinskaya st. 10, 119121, Moscow, Russia
| | - A Zöllner
- Saarland University, Saarbrücken, Germany
| | - N V Medvedeva
- Institute of Biomedical Chemistry RAMS, Pogodinskaya st. 10, 119121, Moscow, Russia
| | - A I Archakov
- Institute of Biomedical Chemistry RAMS, Pogodinskaya st. 10, 119121, Moscow, Russia
| | - W Reinle
- Saarland University, Saarbrücken, Germany
| | | |
Collapse
|
11
|
Schiffler B, Zöllner A, Bernhardt R. Kinetic and optical biosensor study of adrenodoxin mutant AdxS112W displaying an enhanced interaction towards the cholesterol side chain cleavage enzyme (CYP11A1). EUROPEAN BIOPHYSICS JOURNAL: EBJ 2011; 40:1275-82. [PMID: 21526428 DOI: 10.1007/s00249-011-0703-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 03/18/2011] [Accepted: 03/26/2011] [Indexed: 10/18/2022]
Abstract
In mammals, steroid hormones are synthesized from cholesterol that is metabolized by the mitochondrial CYP11A1 system leading to pregnenolone. The reduction equivalents for this reaction are provided by NADPH, via a small electron transfer chain, consisting of adrenodoxin reductase (AdR) and adrenodoxin (Adx). The reaction partners are involved in a series of transient interactions to realize the electron transfer from NADPH to CYP11A1. Here, we compared the ionic strength effect on the AdR/Adx and Adx/CYP11A1 interactions for wild-type Adx and mutant AdxS112W. Using surface plasmon resonance measurements, stopped flow kinetic investigations and analyses of the product formation, we were able to obtain new insights into the mechanism of these interactions. The replacement of serine 112 by tryptophan was demonstrated to lead to a dramatically decreased k (off) rate of the Adx/CYP11A1 complex, resulting in a four-fold decreased K (d) value and indicating a much higher stability of the complex involving the mutant. Stopped flow analysis at various ionic strengths and in different mixing modes revealed that the binding of reduced Adx to CYP11A1 seems to display the limiting step for electron transfer to CYP11A1 with pre-reduced AdxS112W being much more efficient than wild-type Adx. Finally, the dramatic increase in pregnenolone formation at higher ionic strength using the mutant demonstrates that the interaction of CYP11A1 with Adx is the rate-limiting step in substrate conversion and that hydrophobic interactions may considerably improve this interaction and the efficiency of product formation. The data are discussed using published structural data of the complexes.
Collapse
Affiliation(s)
- Burkhard Schiffler
- Naturwissenschaftlich-Technische Fakultät III, Lehrstuhl für Biochemie, Universität des Saarlandes, Saarbrücken, Germany
| | | | | |
Collapse
|
12
|
SASAKI KEN, OKAMOTO TADASHI, OKA SHINZABURO, KUNICHIKA SANGO. KINETIC STUDY OF AEROBIC CARBON-CARBON BOND CLEAVAGE OF 1,2-DIARYLETHANEDIOL CATALYZED BY BALDWIN'S CAPPED PORPHYRIN IRON COMPLEX. CHEM ENG COMMUN 2010. [DOI: 10.1080/00986448908940656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- KEN SASAKI
- a Institute for Chemical Research , Kyoto University, Uji, Kyoto,
- 611
- Japan
| | - TADASHI OKAMOTO
- a Institute for Chemical Research , Kyoto University, Uji, Kyoto,
- 611
- Japan
| | - SHINZABURO OKA
- a Institute for Chemical Research , Kyoto University, Uji, Kyoto,
- 611
- Japan
| | - SANGO KUNICHIKA
- a Institute for Chemical Research , Kyoto University, Uji, Kyoto,
- 611
- Japan
| |
Collapse
|
13
|
Gunsalus IC, Sligar SG. Oxygen reduction by the P450 monoxygenase systems. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 47:1-44. [PMID: 364937 DOI: 10.1002/9780470122921.ch1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
14
|
Lieberman S, Ma S, He Y. New assumptions about oxidative processes involved in steroid hormone biosynthesis: is the role of cytochrome P-450-activated dioxygen limited to hydroxylation reactions or are dioxygen insertion reactions also possible? J Steroid Biochem Mol Biol 2005; 94:405-20. [PMID: 15876406 DOI: 10.1016/j.jsbmb.2004.12.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Accepted: 12/30/2004] [Indexed: 10/25/2022]
Abstract
The traditional conception of the chemical pathways leading to the formation of the steroid hormones is derived by piecing together the results of several independent in vitro incubation experiments. The results of these experiments have led to the assumption that some relevant cytochrome P-450's (P-450scc, P-450arom, P-450aldo, etc.) are "polyfunctional" and catalyze several successive hydroxylation reactions, which lead to the formation of the hormonal products. This essay offers an alternative view. It advances the suggestion that the oxygenated intermediates in the relevant biosynthetic conversions are reactive species that are formed by addition of both atoms of dioxygen onto two neighboring carbon atoms of steroidal precursors. Space-filled Stuart molecular models, generated by a computer program, suggest that the oxidized intermediates resemble hydroperoxides or cyclic peroxides (1,2-dioxanes). For the aromatization process required for estrogen biosynthesis, the atoms of dioxygen are bonded to C-2 and C-19 of the C19-precursor. For aldosterone formation, dioxygen is bonded to C-11 and C-18 of an appropriate precursor. Moreover, the results obtained from a computer program that provides information about "molecular mechanics" (bond angles and bond distances as well as total potential energies for each conformation of a molecule) suggest that consideration be given to the possibility that cortisol also can be biosynthesized by P-450-activated dioxygen addition to C-11 and C-17 of an appropriate precursor. Neither the traditional view of steroidogenic pathways nor the suggestions advanced here have been established by compelling experimental findings. Both hypotheses are saddled with untested assumptions, which are necessary because the dynamic processes can only be discerned by indirect means. The origins of some naturally occurring steroids hydroxylated at C-17, C-18 and C-19 are examined in the light of the suggestions made in this essay.
Collapse
Affiliation(s)
- Seymour Lieberman
- Department of Obstetrics and Gynecology, Institute for Health Sciences, St. Luke's/Roosevelt Hospital Center, 432 West 58th Street, New York, NY 10019, USA.
| | | | | |
Collapse
|
15
|
Umehara K, Shimokawa Y, Koga T, Ohtani T, Miyamoto G. Oxidative one-carbon cleavage of the octyl side chain of olanexidine, a novel antimicrobial agent, in dog liver microsomes. Xenobiotica 2005; 34:61-71. [PMID: 14742137 DOI: 10.1080/00498250310001646335] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
1. The oxidative one-carbon cleavage reaction in the octyl side chain of olanexidine [1-(3,4-dichlorobenzyl)-5-octylbiguanide], a new potent biguanide antiseptic, was characterized in dog liver microsomes. 2. Olanexidine was initially biotransformed to a monohydroxylated metabolite, 8-[5-(3,4-dichlorobenzyl)-1-biguanidino]-2-octanol (DM-215), and DM-215 was subsequently oxidized to the diol derivative, 8-[5-(3,4-dichlorobenzyl)-1-biguanidino]-1,2-octandiol (DM-220). DM-220 was further biotransformed to 2-hydroxy aldehyde derivative, 2-hydroxy carboxylic acid derivative, and an oxidative C-1-C-2 bond cleavage metabolite, 7-[5-(3,4-dichlorobenzyl)-1-biguanidino] heptanoic acid [DM-223 (C7), a seven-carbon chain derivative], after incubation with dog liver microsomes. 3. DM-223 formation required NADPH as a cofactor and was inhibited by quinidine and quinine, relatively selective inhibitors of CYP2D subfamilies in dogs. 4. The results suggest that the one-carbon fragment of the octyl side chain of olanexidine could be removed by the oxidative C-C bond cleavage with the possible involvement of cytochrome P450 systems such as CYP2D subfamily. This oxidative C-C bond cleavage reaction by cytochrome P450s could play an important role in the removal of one-carbon fragment of other drugs or endogenous compounds containing aliphatic chains.
Collapse
Affiliation(s)
- K Umehara
- Tokushima Research Institute, Otsuka Pharmaceutical Co., Ltd, Japan.
| | | | | | | | | |
Collapse
|
16
|
Schiffler B, Zöllner A, Bernhardt R. Stripping down the mitochondrial cholesterol hydroxylase system, a kinetics study. J Biol Chem 2004; 279:34269-76. [PMID: 15181009 DOI: 10.1074/jbc.m402798200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The origin of steroid hormones in mammals is cholesterol that is metabolized by the mitochondrial CYP11A1 system. The cytochrome P450 is fed with reduction equivalents via a small electron transfer chain consisting of NADPH, adrenodoxin reductase, and adrenodoxin. Though the redox behavior of the individual protein components has been studied previously, the kinetics of the system in its entirety has not yet been analyzed. In this study we combine surface plasmon resonance experiments to determine the binding constants for the different pairs of redox partners with measurements of the pre-steady-state kinetics of the different reaction steps of this system and steady-state kinetics. We could correlate the individual protein-protein interactions with the effect of distinct reduction-oxidation steps on the overall catalytic activity of the CYP11A1 system. For the first time, we were able to follow the reduction of each of the protein components of this system within one measurement when we mixed all oxidized protein components with NADPH. These measurements allowed the determination of the individual apparent rate constants for the reduction of all three proteins involved. In addition, variation of the ionic strength in these experiments revealed different optimum salt concentrations for the reduction of adrenodoxin reductase and adrenodoxin, respectively, and unraveled dramatically changing reduction rates of CYP11A1 by adrenodoxin.
Collapse
Affiliation(s)
- Burkhard Schiffler
- Naturwissenschaftlich-Technische Fakultät III, FR 8.8-Biochemie, Universität des Saarlandes, P. O. Box 151150, D-66041 Saarbrücken, Germany
| | | | | |
Collapse
|
17
|
Morisaki M, Sato S, Ikekawa N, Shikita M. Stereochemical specificity at carbon-20 and -22 of hydroxylated cholesterols for side-chain cleavage by adrenocortical cytochrome P
-450scc. FEBS Lett 2001; 72:337-40. [PMID: 16386053 DOI: 10.1016/0014-5793(76)80999-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- M Morisaki
- Laboratory of Chemistry for Natural Products, Tokyo Institute of Technology, Meguro-Ku, Tokyo 152, Japan
| | | | | | | |
Collapse
|
18
|
Schiffler B, Kiefer M, Wilken A, Hannemann F, Adolph HW, Bernhardt R. The interaction of bovine adrenodoxin with CYP11A1 (cytochrome P450scc) and CYP11B1 (cytochrome P45011beta ). Acceleration of reduction and substrate conversion by site-directed mutagenesis of adrenodoxin. J Biol Chem 2001; 276:36225-32. [PMID: 11459837 DOI: 10.1074/jbc.m102320200] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The kinetics of protein-protein interaction and heme reduction between adrenodoxin wild type as well as eight mutants and the cytochromes P450 CYP11A1 and CYP11B1 was studied in detail. Rate constants for the formation of the reduced CYP11A1.CO and CYP11B1.CO complexes by wild type adrenodoxin, the adrenodoxin mutants Adx-(4-108), Adx-(4-114), T54S, T54A, and S112W, and the double mutants Y82F/S112W, Y82L/S112W, and Y82S/S112W (the last four mutants are Delta113-128) are presented. The rate constants observed differ by a factor of up to 10 among the respective adrenodoxin mutants for CYP11A1 but not for CYP11B1. According to their apparent rate constants for CYP11A1, the adrenodoxin mutants can be grouped into a slow (wild type, T54A, and T54S) and a fast group (all the other mutants). The adrenodoxin mutants forming the most stable complexes with CYP11A1 show the fastest rates of reduction and the highest rate constants for cholesterol to pregnenolone conversion. This strong correlation suggests that C-terminal truncation of adrenodoxin in combination with the introduction of a C-terminal tryptophan residue enables a modified protein-protein interaction rendering the system almost as effective as the bacterial putidaredoxin/CYP101 system. Such a variation of the adrenodoxin structure resulted in a mutant protein (S112W) showing a 100-fold increased efficiency in conversion of cholesterol to pregnenolone.
Collapse
Affiliation(s)
- B Schiffler
- Universität des Saarlandes, FR 8.8 Biochemie, P.O. Box 151150, D-66041 Saarbrücken, Germany
| | | | | | | | | | | |
Collapse
|
19
|
Grinberg AV, Hannemann F, Schiffler B, Müller J, Heinemann U, Bernhardt R. Adrenodoxin: structure, stability, and electron transfer properties. Proteins 2000; 40:590-612. [PMID: 10899784 DOI: 10.1002/1097-0134(20000901)40:4<590::aid-prot50>3.0.co;2-p] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Adrenodoxin is an iron-sulfur protein that belongs to the broad family of the [2Fe-2S]-type ferredoxins found in plants, animals and bacteria. Its primary function as a soluble electron carrier between the NADPH-dependent adrenodoxin reductase and several cytochromes P450 makes it an irreplaceable component of the steroid hormones biosynthesis in the adrenal mitochondria of vertebrates. This review intends to summarize current knowledge about structure, function, and biochemical behavior of this electron transferring protein. We discuss the recently solved first crystal structure of the vertebrate-type ferredoxin, the truncated adrenodoxin Adx(4-108), that offers the unique opportunity for better understanding of the structure-function relationships and stabilization of this protein, as well as of the molecular architecture of [2Fe-2S] ferredoxins in general. The aim of this review is also to discuss molecular requirements for the formation of the electron transfer complex. Essential comparison between bacterial putidaredoxin and mammalian adrenodoxin will be provided. These proteins have similar tertiary structure, but show remarkable specificity for interactions only with their own cognate cytochrome P450. The discussion will be largely centered on the protein-protein recognition and kinetics of adrenodoxin dependent reactions.
Collapse
Affiliation(s)
- A V Grinberg
- Naturwissenschaftlich-Technische Fakultät III, Fachrichtung 8.8 - Biochemie, Universität des Saarlandes, Saarbrücken, Germany
| | | | | | | | | | | |
Collapse
|
20
|
Rabiee AR, Lean IJ, Gooden JM, Miller BG. Relationships among metabolites influencing ovarian function in the dairy cow. J Dairy Sci 1999; 82:39-44. [PMID: 10022004 DOI: 10.3168/jds.s0022-0302(99)75206-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Time series analysis was used to evaluate relationships between the uptake of metabolites, ovarian blood flow, arterial LH concentrations, and the output of steroid hormones by the ovary. There were no significant correlations between cholesterol uptake and progesterone output; therefore, cholesterol uptake was not a factor that immediately limited progesterone output. Although no significant correlations were found between cholesterol and oxygen uptake, significant cross-correlations between the uptake of glucose and oxygen by the ovary at lag 0 indicated some immediate oxidation of glucose. This result strongly indicates that glucose is a major source of energy for the bovine ovary. Arterial LH concentrations had little influence on ovarian metabolism. The examination of interrelationships among factors that influence ovarian function was useful in identifying factors that can limit ovarian activity.
Collapse
Affiliation(s)
- A R Rabiee
- Department of Veterinary Science, University of Melbourne, Werribee, Australia
| | | | | | | |
Collapse
|
21
|
Takahashi M, Kayo T, Karakida T, Nakagawa S, Kato M, Matsuno S, Koide Y, Sakato M, Kawashima S. Potent and selective aromatase inhibitor: in vitro and in vivo studies with s-triazine derivative SEF19. Endocr Res 1997; 23:1-13. [PMID: 9187534 DOI: 10.1080/07435809709031838] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We found a potent aromatase inhibitor through the screening of agents for estrogen-dependent breast cancer. SEF19 (2-(imidazol-1-yl)-4,6-dimorphorino-1,3,5-triazine) decreased 50% of human placental aromatase activity in vitro at the concentration of 5.3 nM. In order to clarify the selectivity of SEF19 for enzyme inhibition, we determined the effect of SEF19 on the activities of four steroidogenic cytochrome P450 enzymes in porcine adrenal gland, P450SCC(side-chain cleavage of cholesterol), P450(11 beta) (11 beta-hydroxylase), P450(17 alpha)(17 alpha-hydroxylase/C17,20 lyase) and P450C21 (21-hydroxylase). SEF19 failed to inhibit the activities of porcine adrenal P450SCC, P450(17 alpha) and P450C21 up to the concentration of 100 microM and showed some inhibition on P450(11 beta) activity at 100 microM, while SEF19 completely nullified the aromatase activity at 1 microM. We also determined the potency of SEF19 for the suppression of aromatase activity in vivo. SEF19 suppressed dose-dependently the uterine hypertrophy of immature rats caused by administration of androstenedione (30 mg/kg, s.c.). The ED50 of SEF19 for the suppression of uterine hypertrophy was 0.8 mumol/kg. These results suggest that SEF19 may serve as a potent and selective agent for the treatment of estrogen-dependent breast cancer.
Collapse
Affiliation(s)
- M Takahashi
- Research Laboratory, Zenyaku Kogyo Co., Ltd., Tokyo, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
On The Mechanism of Ironporphyrin-Catalyzed Aerobic Carbon-Carbon Bond Cleavage of Vic-Diols in the Presence of Nad (P) H Model Compounds. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/s0167-2991(08)62831-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
23
|
Prasad VV, Lieberman S. Master lecture. Reconsidering some of the biosynthetic pathways leading to formation of C19-steroids. Ann N Y Acad Sci 1990; 595:1-16. [PMID: 2197965 DOI: 10.1111/j.1749-6632.1990.tb34278.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- V V Prasad
- Department of Obstetrics and Gynecology, St. Luke's-Roosevelt Institute for Health Sciences, New York, New York 10019
| | | |
Collapse
|
24
|
Tuckey RC, Atkinson HC. Pregnenolone synthesis from cholesterol and hydroxycholesterols by mitochondria from ovaries following the stimulation of immature rats with pregnant mare's serum gonadotropin and human choriogonadotropin. EUROPEAN JOURNAL OF BIOCHEMISTRY 1989; 186:255-9. [PMID: 2598930 DOI: 10.1111/j.1432-1033.1989.tb15203.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The rate of pregnenolone synthesis by cytochrome P-450scc was measured in mitochondria isolated from ovaries of immature rats treated with pregnant mare's serum gonadotropin and human choriogonadotropin. Using cholesterol, 25-hydroxycholesterol, 20 alpha-hydroxycholesterol, (22R)-22-hydroxycholesterol and (22R)-20 alpha,22-dihydroxycholesterol as substrates, we have determined that the first hydroxylation of cholesterol, in the 22R position, is rate limiting in pregnenolone synthesis. It proceeds at only 22% of the rate of either of the subsequent two hydroxylations. 25-Hydroxycholesterol proved to be a suitable substrate for determining the maximum rate of pregnenolone synthesis by cytochrome P-450scc in isolated mitochondria. The maximum rate was 13 mol steroid.min-1.mol cytochrome P-450scc-1 and did not change after the follicles in the immature ovary had been stimulated to mature and luteinize with gonadotropin. Using endogenous cholesterol in isolated mitochondria as substrate, the time course of pregnenolone synthesis was the same during the follicular phase as in the luteal stage of gonadotropin-induced development. We conclude that during the artificial induced development of follicles in the immature ovary, the major cause of the increase in the rate of pregnenolone synthesis is the increase in the cytochrome P-450scc content of the mitochondria, rather than changes in the catalytic activity of cytochrome P-450scc or the cholesterol availability to the cytochrome.
Collapse
Affiliation(s)
- R C Tuckey
- Department of Biochemistry, University of Western Australia, Perth
| | | |
Collapse
|
25
|
Tsubaki M, Iwamoto Y, Hiwatashi A, Ichikawa Y. Inhibition of electron transfer from adrenodoxin to cytochrome P-450scc by chemical modification with pyridoxal 5'-phosphate: identification of adrenodoxin-binding site of cytochrome P-450scc. Biochemistry 1989; 28:6899-907. [PMID: 2819041 DOI: 10.1021/bi00443a019] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Covalent modification of cytochrome P-450scc (purified from bovine adrenocortical mitochondria) with pyridoxal 5'-phosphate (PLP) was found to cause inhibition of the electron-accepting ability of this enzyme from its physiological electron donor, adrenodoxin, without conversion to the "P-420" form. Reaction conditions leading to the modification level of 0.82 and 2.85 PLP-Lys residues per cytochrome P-450scc molecule resulted in 60% and 98% inhibition, respectively, of electron-transfer rate from adrenodoxin to cytochrome P-450scc (with beta-NADPH as an electron donor via NADPH-adrenodoxin reductase and with phenyl isocyanide as the exogenous heme ligand of the cytochrome). It was found that covalent PLP modification caused a drastic decrease of cholesterol side-chain cleavage activity when the cholesterol side-chain cleavage enzyme system was reconstituted with native (or PLP-modified) cytochrome P-450scc, adrenodoxin, and NADPH-adrenodoxin reductase. Approximately 60% of the original enzymatic activity of cytochrome P-450scc was protected against inactivation by covalent PLP modification when 20% mole excess adrenodoxin was included during incubation with PLP. Binding affinity of substrate (cholesterol) to cytochrome P-450scc was found to be increased slightly upon covalent modification with PLP by analyzing a substrate-induced spectral change. The interaction of adrenodoxin with cytochrome P-450scc in the absence of substrate (cholesterol) was analyzed by difference absorption spectroscopy with a four-cuvette assembly, and the apparent dissociation constant (Ks) for adrenodoxin binding was found to be increased from 0.38 microM (native) to 33 microM (covalently PLP modified).(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- M Tsubaki
- Department of Biochemistry, Kagawa Medical School, Japan
| | | | | | | |
Collapse
|
26
|
Trzaskos JM, Fischer RT, Favata MF. Mechanistic studies of lanosterol C-32 demethylation. Conditions which promote oxysterol intermediate accumulation during the demethylation process. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(19)75980-8] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
27
|
|
28
|
Mitani F, Iizuka T, Shimada H, Ueno R, Ishimura Y. Flash photolysis studies on the CO complexes of ferrous cytochrome P-450scc and cytochrome P-45011 beta. Effects of steroid binding on the photochemical and ligand binding properties. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(17)38982-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|
29
|
Whitesides GM, Wong CH. Enzymes as Catalysts in Synthetic Organic Chemistry [New Synthetic Methods (53)]. ACTA ACUST UNITED AC 1985. [DOI: 10.1002/anie.198506173] [Citation(s) in RCA: 361] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
30
|
|
31
|
Hall PF. Trophic stimulation of steroidogenesis: in search of the elusive trigger. RECENT PROGRESS IN HORMONE RESEARCH 1985; 41:1-39. [PMID: 2996086 DOI: 10.1016/b978-0-12-571141-8.50005-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
|
32
|
Hall PF. Role of cytochromes P-450 in the biosynthesis of steroid hormones. VITAMINS AND HORMONES 1985; 42:315-68. [PMID: 3913122 DOI: 10.1016/s0083-6729(08)60065-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
33
|
Adrenodoxin interaction with adrenodoxin reductase and cytochrome P-450scc. Cross-linking of protein complexes and effects of adrenodoxin modification by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(18)90921-x] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
34
|
Gorsky LD, Koop DR, Coon MJ. On the stoichiometry of the oxidase and monooxygenase reactions catalyzed by liver microsomal cytochrome P-450. Products of oxygen reduction. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(17)39800-9] [Citation(s) in RCA: 257] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
35
|
Abstract
The discovery of a role for the cytoskeleton in the responses to ACTH and cyclic AMP was somewhat unexpected - at least this was the case 9 years ago (1). In fact, many endocrinologists are forced to confess that they were innocent of any understanding of the cytoskeleton and were not even aware that all mammalian cells possess microfilaments and microtubules. A new generation of endocrinologists has arrived on the scene who have been brought up with the cytoskeleton so that we can expect to see considerable progress during the coming decade in our understanding of the role of the cytoskeleton in endocrine cells.
Collapse
|
36
|
|
37
|
Kinetics of O2 and CO Binding to adrenal cytochrome P-450scc. Effect of cholesterol, intermediates, and phosphatidylcholine vesicles. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(18)32611-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
38
|
Inhibition of adrenocortical cytochrome P-450scc by (20R)-20-phenyl-5-pregnene-3 beta,20-diol. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(18)32741-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
39
|
Sheets JJ, Vickery LE. C-22-substituted steroid derivatives as substrate analogues and inhibitors of cytochrome P-450scc. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(18)33045-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
40
|
19 P-450 Oxygenases in Lipid Transformation. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/s1874-6047(08)60317-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
|
41
|
Sheets JJ, Vickery LE. Proximity of the substrate binding site and the heme-iron catalytic site in cytochrome P-450scc. Proc Natl Acad Sci U S A 1982; 79:5773-7. [PMID: 6964388 PMCID: PMC346992 DOI: 10.1073/pnas.79.19.5773] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
As an approach to "mapping" the active site of the cytochrome P-450 that catalyzes cholesterol side-chain cleavage, designated cytochrome P-450scc, we have synthesized steroid derivatives with the potential to interact with both the substrate binding site and the heme-iron catalytic site of the enzyme. The effects of these substrate analogs were studied with cytochrome P-450scc purified from bovine adrenal cortex. One derivative, 22-amino-23,24-bisnor-5-cholen-3 beta-ol, was found to be a potent inhibitor of pregnenolone formation in a reconstituted enzyme system, and a kinetic analysis of the inhibition showed that binding of the derivative is competitive with respect to cholesterol. The spectral properties of a stable complex formed between the steroidal amine and the purified cytochrome suggest that the 22-amine group coordinates directly to the heme-iron. A model for the structure of this inhibitor-enzyme complex is proposed in which the 5-androstene ring system of the steroid occupies the substrate binding site, and the amine group of the side chain occupies an axial coordination position of the Fe(III) center. This places limits on the distance between these two domains in the enzyme and offers support for proposed mechanisms of cytochrome P-450-catalyzed oxygen-insertion reactions in which an iron-bound oxidant directly attacks the substrate.
Collapse
|
42
|
Tuckey RC, Kamin H. The oxyferro complex of adrenal cytochrome P-450scc. Effect of cholesterol and intermediates on its stability and optical characteristics. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(18)34070-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
43
|
|
44
|
Lambeth J, Kitchen S, Farooqui A, Tuckey R, Kamin H. Cytochrome P-450scc-substrate interactions. Studies of binding and catalytic activity using hydroxycholesterols. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(19)68119-6] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
45
|
ASCOLI MARIO. Regulation of Steroid Production in Adrenal, Gonadal, and Placental Tumor Cells. CELLULAR REGULATION OF SECRETION AND RELEASE 1982:409-444. [DOI: 10.1016/b978-0-12-185058-6.50019-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
|
46
|
Nakajin S, Shively JE, Yuan PM, Hall PF. Microsomal cytochrome P-450 from neonatal pig testis: two enzymatic activities (17 alpha-hydroxylase and c17,20-lyase) associated with one protein. Biochemistry 1981; 20:4037-42. [PMID: 6793062 DOI: 10.1021/bi00517a014] [Citation(s) in RCA: 222] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Studies have been performed to test the hypothesis that cytochrome P-450 from testicular microsomes consists of a single protein with two enzymatic activities (17 alpha-hydroxylase and C17,20-lyase). Three lines of evidence to support the hypothesis were obtained. (1) The enzyme appears to be homogeneous by immunochemical criteria with anti-P-450 IgG (line of identity on immunodiffusion and a single band on immunoelectrophoresis), by demonstration of a single NH2-terminal amino acid (methionine) and the finding of 16 single amino acids at the NH2 terminus. (2) Optima for pH and temperature are the same for both enzymatic activities (pH 7.25 and 37 degrees C), and temperatures between 30 and 44 degrees C decreased both activities in such a way that the ratio of hydroxylase to lyase was the same at all temperatures tested. (3) A variety of inhibitors affect both activities to the same extent: Ki values for two competitive inhibitors (SU 8000, 0.04 microM; SU 10603, 0.3 microM) are the same for hydroxylase and lyase; partition coefficients for inhibition by carbon monoxide are similar for hydroxylase and lyase (20 +/- 2 and 27 +/- 3); anti-P-450 (serum and IgG) causes inhibition of both activities to the same extent, and the same is true of a variety of less specific inhibitors. It is concluded that a single heme protein (cytochrome P-450) from microsomes of neonatal pig testis catalyzes two reactions (hydroxylase and lyase) which are sequential steps in the synthesis of androgens by the testis leading to conversion of C21 precursors to C19 steroid hormones.
Collapse
|
47
|
Hanukoglu I, Spitsberg V, Bumpus JA, Dus KM, Jefcoate CR. Adrenal mitochondrial cytochrome P-450scc. Cholesterol and adrenodoxin interactions at equilibrium and during turnover. J Biol Chem 1981; 256:4321-8. [PMID: 7217084 DOI: 10.1016/s0021-9258(19)69436-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
|
48
|
Nakajin S, Hall P. Microsomal cytochrome P-450 from neonatal pig testis. Purification and properties of A C21 steroid side-chain cleavage system (17 alpha-hydroxylase-C17,20 lyase). J Biol Chem 1981. [DOI: 10.1016/s0021-9258(19)69538-4] [Citation(s) in RCA: 139] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
49
|
Strauss JF, Schuler LA, Rosenblum MF, Tanaka T. Cholesterol metabolism by ovarian tissue. ADVANCES IN LIPID RESEARCH 1981; 18:99-157. [PMID: 6275662 DOI: 10.1016/b978-0-12-024918-3.50009-5] [Citation(s) in RCA: 73] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
50
|
Light D, Walsh C. Flavin analogs as mechanistic probes of adrenodoxin reductase-dependent electron transfer to the cholesterol side chain cleavage cytochrome P-450 of the adrenal cortex. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)85662-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|