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Gupte SA, Bakshi CS, Blackham E, Duhamel GE, Jordan A, Salgame P, D'silva M, Khan MY, Nadler J, Gupte R. The severity of SARS-CoV-2 infection in K18-hACE2 mice is attenuated by a novel steroid-derivative in a gender-specific manner. Br J Pharmacol 2023; 180:2677-2693. [PMID: 37259182 PMCID: PMC10999099 DOI: 10.1111/bph.16155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 06/02/2023] Open
Abstract
BACKGROUND AND PURPOSE COVID-19 infections caused by SARS-CoV-2 disseminated through human-to-human transmission can evoke severe inflammation. Treatments to reduce the SARS-CoV-2-associated inflammation are needed and are the focus of much research. In this study, we investigated the effect of N-ethyl-N'-[(3β,5α)-17-oxoandrostan-3-yl] urea (NEOU), a novel 17α-ketosteroid derivative, on the severity of COVID-19 infections. EXPERIMENTAL APPROACH Studies were conducted in SARS-CoV-2-infected K18-hACE2 mice. KEY RESULTS SARS-CoV-2-infected K18-hACE2 mice developed severe inflammatory crises and immune responses along with up-regulation of genes in associated signalling pathways in male more than female mice. Notably, SARS-CoV-2 infection down-regulated genes encoding drug metabolizing cytochrome P450 enzymes in male but not female mice. Treatment with NEOU (1 mg·kg-1 ·day-1 ) 24 or 72 h post-viral infection alleviated lung injury by decreasing expression of genes encoding inflammatory cytokines and chemokines while increasing expression of genes encoding immunoglobins. In situ hybridization using RNA scope™ probes and immunohistochemical assays revealed that NEOU increased resident CD169+ immunoregulatory macrophages and IBA-1 immunoreactive macrophage-dendritic cells within alveolar spaces in the lungs of infected mice. Consequentially, NEOU reduced morbidity more prominently in male than female mice. However, NEOU increased median survival time and accelerated recovery from infection by 6 days in both males and females. CONCLUSIONS AND IMPLICATIONS These findings demonstrate that SARS-CoV-2 exhibits gender bias by differentially regulating genes encoding inflammatory cytokines, immunogenic factors and drug-metabolizing enzymes, in male versus female mice. Most importantly, we identified a novel 17α-ketosteroid that reduces the severity of COVID-19 infection and could be beneficial for reducing impact of COVID-19.
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Affiliation(s)
- Sachin A Gupte
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
| | - Chandra Shekhar Bakshi
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, New York, USA
| | | | - Gerald E Duhamel
- Department of Biomedical Sciences and New York State Animal Health Diagnostic Center and Section of Anatomic Pathology, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | | | - Padmini Salgame
- Department of Medicine, Division of Infectious Diseases and The Center for Emerging Pathogens, Rutgers-New Jersey Medical School, Newark, New Jersey, USA
| | - Melinee D'silva
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
| | - Mohammad Y Khan
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
| | - Jerry Nadler
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
- Department of Medicine, New York Medical College, Valhalla, New York, USA
| | - Rakhee Gupte
- Department of Pharmacology, New York Medical College, Valhalla, New York, USA
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2
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Hubert SM, Samollow PB, Lindström H, Mannervik B, Ing NH. Conservation of Glutathione Transferase mRNA and Protein Sequences Similar to Human and Horse Alpha Class GST A3-3 across Dog, Goat, and Opossum Species. Biomolecules 2023; 13:1420. [PMID: 37759820 PMCID: PMC10526480 DOI: 10.3390/biom13091420] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 08/29/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023] Open
Abstract
The glutathione transferase A3-3 (GST A3-3) homodimeric enzyme is the most efficient enzyme that catalyzes isomerization of the precursors of testosterone, estradiol, and progesterone in the gonads of humans and horses. However, the presence of GST A3-3 orthologs with equally high ketosteroid isomerase activity has not been verified in other mammalian species, even though pig and cattle homologs have been cloned and studied. Identifying GSTA3 genes is a challenge because of multiple GSTA gene duplications (e.g., 12 in the human genome); consequently, the GSTA3 gene is not annotated in most genomes. To improve our understanding of GSTA3 gene products and their functions across diverse mammalian species, we cloned homologs of the horse and human GSTA3 mRNAs from the testes of a dog, goat, and gray short-tailed opossum, the genomes of which all currently lack GSTA3 gene annotations. The resultant novel GSTA3 mRNA and inferred protein sequences had a high level of conservation with human GSTA3 mRNA and protein sequences (≥70% and ≥64% identities, respectively). Sequence conservation was also apparent for the 12 residues of the "H-site" in the 222 amino acid GSTA3 protein that is known to interact with the steroid substrates. Modeling predicted that the dog GSTA3-3 may be a more active ketosteroid isomerase than the corresponding goat or opossum enzymes. However, expression of the GSTA3 gene was higher in liver than in other dog tissue. Our results improve understanding of the active sites of mammalian GST A3-3 enzymes, inhibitors of which might be useful for reducing steroidogenesis for medical purposes, such as fertility control or treatment of steroid-dependent diseases.
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Affiliation(s)
- Shawna M. Hubert
- Department of Animal Science, Texas A&M AgriLife Research, Texas A&M University, College Station, TX 77843-2471, USA; (S.M.H.); (N.H.I.)
- Department of Thoracic Head & Neck Medical Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030-4000, USA
| | - Paul B. Samollow
- Department of Veterinary Integrative Biosciences, School of Veterinary Medicine and Biosciences, Texas A&M University, College Station, TX 77843-2471, USA;
| | - Helena Lindström
- Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, SE-10691 Stockholm, Sweden;
| | - Bengt Mannervik
- Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, SE-10691 Stockholm, Sweden;
| | - Nancy H. Ing
- Department of Animal Science, Texas A&M AgriLife Research, Texas A&M University, College Station, TX 77843-2471, USA; (S.M.H.); (N.H.I.)
- Faculty of Biotechnology, Texas A&M University, College Station, TX 77843-2128, USA
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Pham AHN, Thi KOB, Thi MHN, Ngo DN, Naritaka N, Nittono H, Hayashi H, Dao TT, Nguyen KHT, Nguyen HN, Giang H, Tang HS, Nguyen TT, Truong DK, Tran MD. Clinical and genetic features of congenital bile acid synthesis defect with a novel mutation in AKR1D1 gene sequencing: Case reports. Medicine (Baltimore) 2022; 101:e29476. [PMID: 35758383 PMCID: PMC9276355 DOI: 10.1097/md.0000000000029476] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 04/29/2022] [Indexed: 11/26/2022] Open
Abstract
RATIONALE Congenital bile acid synthesis defect (BASD) is a rare disease caused by mutations in the aldo-keto reductase 1D1 gene, which encodes the primary Δ4-3-oxosteroid 5β-reductase enzyme. Early disease diagnosis is critical for early treatment with bile acid replacement therapy, with an excellent chance for recovery. In contrast, protracted diagnosis and treatment may lead to poor outcomes, including decompensated hepatic cirrhosis, liver transplant, and even death. PATIENT CONCERNS Three clinical congenital bile acid synthesis defect cases in the Vietnamese population are herein reported. These pediatric patients presented with symptoms of prolonged postpartum jaundice and abnormal loose stool (mucus, lipids, and white). The clinical examinations showed hepatosplenomegaly. Urinalysis showed a very low fraction of primary bile acids and atypical 3-oxo-Δ4- bile acids in all three patients. DIAGNOSES The patients were diagnosed with primary Δ4-3-oxosteroid 5β-reductase deficiency. Next-generation gene sequencing revealed two homozygous mutations in the aldo-keto reductase family 1 member D1 gene. The first is a documented variant, c.797G>A (p.Arg266Gln), and the second is a novel mutation at c.155T>C (p.Ile52Thr). INTERVENTIONS Immediately after diagnosis, patients were treated with oral chenodeoxycholate 5 mg/kg/d. OUTCOMES The patients' symptoms, signs, and primary bile acids levels improved significantly. LESSONS Clinicians should consider genetic disorders related to cholestasis for effective and life-saving treatment. A prompt genetic analysis by next-generation gene sequencing enables patients to access bile acid replacement therapy earlier, significantly improving short- and long-term outcomes.
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Affiliation(s)
| | - Kim-Oanh Bui Thi
- Hepatology Department, National Children's Hospital, Hanoi, Vietnam
| | | | - Diem-Ngoc Ngo
- Human Genetics Department, National Children's Hospital, Hanoi, Vietnam
| | | | - Hiroshi Nittono
- Laboratory of Molecular Pharmacokinetics, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Hisamitsu Hayashi
- Laboratory of Molecular Pharmacokinetics, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Trang Thi Dao
- Gene Solutions, Ho Chi Minh City, Vietnam
- Medical Genetics Institutes, Ho Chi Minh City, Vietnam
| | - Kim-Huong Thi Nguyen
- Gene Solutions, Ho Chi Minh City, Vietnam
- Medical Genetics Institutes, Ho Chi Minh City, Vietnam
| | - Hoai-Nghia Nguyen
- Medical Genetics Institutes, Ho Chi Minh City, Vietnam
- University of Medicine and Pharmacy at Ho Chi Minh City, Vietnam
| | - Hoa Giang
- Gene Solutions, Ho Chi Minh City, Vietnam
- Medical Genetics Institutes, Ho Chi Minh City, Vietnam
| | - Hung-Sang Tang
- Gene Solutions, Ho Chi Minh City, Vietnam
- Medical Genetics Institutes, Ho Chi Minh City, Vietnam
| | - Tat-Thanh Nguyen
- Gene Solutions, Ho Chi Minh City, Vietnam
- Medical Genetics Institutes, Ho Chi Minh City, Vietnam
| | | | - Minh-Dien Tran
- Hepatology Department, National Children's Hospital, Hanoi, Vietnam
- Human Genetics Department, National Children's Hospital, Hanoi, Vietnam
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Mautschke H, Llabrés i Xamena FX. One-Step Chemo-, Regio- and Stereoselective Reduction of Ketosteroids to Hydroxysteroids over Zr-Containing MOF-808 Metal-Organic Frameworks. Chemistry 2021; 27:10766-10775. [PMID: 33998732 PMCID: PMC8362071 DOI: 10.1002/chem.202100967] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Indexed: 11/08/2022]
Abstract
Zr-containing MOF-808 is a very promising heterogeneous catalyst for the selective reduction of ketosteroids to the corresponding hydroxysteroids through a Meerwein-Ponndorf-Verley (MPV) reaction. Interestingly, the process leads to the diastereoselective synthesis of elusive 17α-hydroxy derivatives in one step, whereas most chemical and biological transformations produce the 17β-OH compounds, or they require several additional steps to convert 17β-OH into 17α-OH by inverting the configuration of the 17 center. Moreover, MOF-808 is found to be stable and reusable; it is also chemoselective (only keto groups are reduced, even in the presence of other reducible groups such as C=C bonds) and regioselective (in 3,17-diketosteroids only the keto group in position 17 is reduced, while the 3-keto group remains almost intact). The kinetic rate constant and thermodynamic parameters of estrone reduction to estradiol have been obtained by a detailed temperature-dependent kinetic analysis. The results evidence a major contribution of the entropic term, thus suggesting that the diastereoselectivity of the process is controlled by the confinement of the reaction inside the MOF cavities, where the Zr4+ active sites are located.
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Affiliation(s)
- H.‐H. Mautschke
- Instituto de Tecnología QuímicaUniversitat Politècnica de ValènciaConsejo Superior de Investigaciones CientíficasAvda. de los Naranjos s/n46022ValenciaSpain
| | - F. X. Llabrés i Xamena
- Instituto de Tecnología QuímicaUniversitat Politècnica de ValènciaConsejo Superior de Investigaciones CientíficasAvda. de los Naranjos s/n46022ValenciaSpain
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Rohman A, Dijkstra BW. Application of microbial 3-ketosteroid Δ 1-dehydrogenases in biotechnology. Biotechnol Adv 2021; 49:107751. [PMID: 33823268 DOI: 10.1016/j.biotechadv.2021.107751] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 03/27/2021] [Accepted: 04/02/2021] [Indexed: 11/19/2022]
Abstract
3-Ketosteroid Δ1-dehydrogenase catalyzes the 1(2)-dehydrogenation of 3-ketosteroid substrates using flavin adenine dinucleotide as a cofactor. The enzyme plays a crucial role in microbial steroid degradation, both under aerobic and anaerobic conditions, by initiating the opening of the steroid nucleus. Indeed, many microorganisms are known to possess one or more 3-ketosteroid Δ1-dehydrogenases. In the pharmaceutical industry, 3-ketosteroid Δ1-dehydrogenase activity is exploited to produce Δ1-3-ketosteroids, a class of steroids that display various biological activities. Many of them are used as active pharmaceutical ingredients in drug products, or as key precursors to produce pharmaceutically important steroids. Since 3-ketosteroid Δ1-dehydrogenase activity requires electron acceptors, among other considerations, Δ1-3-ketosteroid production has been industrially implemented using whole-cell fermentation with growing or metabolically active resting cells, in which the electron acceptors are available, rather than using the isolated enzyme. In this review we discuss biotechnological applications of microbial 3-ketosteroid Δ1-dehydrogenases, covering commonly used steroid-1(2)-dehydrogenating microorganisms, the bioprocess for preparing Δ1-3-ketosteroids, genetic engineering of 3-ketosteroid Δ1-dehydrogenases and related genes for constructing new, productive industrial strains, and microbial fermentation strategies for enhancing the product yield. Furthermore, we also highlight the recent development in the use of isolated 3-ketosteroid Δ1-dehydrogenases combined with a FAD cofactor regeneration system. Finally, in a somewhat different context, we summarize the role of 3-ketosteroid Δ1-dehydrogenase in cholesterol degradation by Mycobacterium tuberculosis and other mycobacteria. Because the enzyme is essential for the pathogenicity of these organisms, it may be a potential target for drug development to combat mycobacterial infections.
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Affiliation(s)
- Ali Rohman
- Department of Chemistry, Faculty of Science and Technology, Universitas Airlangga, Surabaya 60115, Indonesia; Laboratory of Proteomics, Research Center for Bio-Molecule Engineering (BIOME), Universitas Airlangga, Surabaya 60115, Indonesia; Laboratory of Biophysical Chemistry, University of Groningen, 9747 AG Groningen, the Netherlands.
| | - Bauke W Dijkstra
- Laboratory of Biophysical Chemistry, University of Groningen, 9747 AG Groningen, the Netherlands.
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6
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Yuan J, Chen G, Cheng S, Ge F, Qiong W, Li W, Li J. [Accumulation of 9α-hydroxy-4-androstene-3,17-dione by co-expressing kshA and kshB encoding component of 3-ketosteroid-9α-hydroxylase in Mycobacterium sp. NRRL B-3805]. Sheng Wu Gong Cheng Xue Bao 2015; 31:523-533. [PMID: 26380409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
9α-hydroxy-4-androstene-3,17-dione (9-OH-AD) is an important intermediate in the steroidal drugs production. 3-ketosteroid-9α-hydroxylase (KSH), a two protein system of KshA and KshB, is a key-enzyme in the microbial steroid ring B-opening pathway. KSH catalyzes the transformation of 4-androstene-3,17-dione (AD) into 9-OH-AD specifically. In the present study, the putative KshA and KshB genes were cloned from Mycobacterium smegmatis mc(2)155 and Gordonia neofelifaecis NRRL B-59395 respectively, and were inserted into the expression vector pNIT, the co-expression plasmids of kshA-kshB were obtained and electroporated into Mycobacterium sp. NRRL B-3805 cells. The recombinants were used to transform steroids, the main product was characterized as 9α-hydroxy-4-androstene-3,17-dione (9-OH-AD), showing that kshA and kshB were expressed successfully. Different from the original strain Mycobacterium sp. NRRL B-3805 that accumulates 4-androstene-3,17-dione, the recombinants accumulates 9α-hydroxy-4-androstene-3,17-dione as the main product. This results indicates that the putative genes kshA, kshB encode active KshA and KshB, respectively. The process of biotransformation was investigated and the results show that phytosterol is the most suitable substrate for biotransformation, kshA and kshB from M. smegmatis mc(2)155 seemed to exhibit high activity, because the resultant recombinant of them catalyzed the biotransformation of phytosterol to 9-OH-AD in a percent conversion of 90%, which was much higher than that of G. neofelifaecis NRRL B-59395. This study on the manipulation of the ksh genes in Mycobacterium sp. NRRL B-3805 provides a new pathway for producing steroid medicines.
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Abstract
Abstract
As little as 0ṁ02 per cent of phenolic steroid may be determined in the presence of an excess of 3-ketosteroid. The interfering ketonic absorption is eliminated by selective reduction of ketone by potassium borohydride. The slight absorption of the reduction products may be corrected graphically.
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Abstract
Abstract
A method is described for the separation of corticosteroids by paper chromatography. It is more sensitive than the present official test and will control the presence of related foreign steroids to a uniform degree and in a reproducible manner. Details of the application of this test to many pharmaceutically important steroids are given and the relationship of molecular structure to mobility in the solvent systems used is discussed.
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HØYER G. Identification and Determination of α, β-Unsaturated Ketosteroids as Girard-T-Hydrazones by Ultraviolet Spectrophotometry. Scandinavian Journal of Clinical and Laboratory Investigation 2009; 3:303-5. [PMID: 14900986 DOI: 10.3109/00365515109060619] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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CHRISTY NP, WALLACE EZ, JAILER JW. The effect of intravenously-administered ACTH on plasma 17,21-dihydroxy-20- ketosteroids in normal individuals and in patients with disorders of the adrenal cortex. J Clin Invest 2003; 34:899-906. [PMID: 14381520 PMCID: PMC1072621 DOI: 10.1172/jci103146] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Abstract
Cell differentiation is essential for normal growth and homeostasis, and drug-induced differentiation of tumor cells into benign or normal cells is an important approach for anticancer chemotherapy. Studies of induction mechanisms for cell differentiation and discovery of differentiation-inducing factors are thus critical components of drug development. The Screening of differentiation-inducing factors, such as purified aldehyde reductase, a xenobiotic metabolite enzyme, that induces differentiation of human acute myeloid leukemia HL60 cells into monocyte/macrophage cells is described. Mechanisms of all-trans-retinoic acid (RA)-induced differentiation are also covered. RA is a potent inducer of HL60 cell differentiation and when used as a sole agent it can induce complete remission in patients with acute promyelocytic leukemia (APL). While one mechanism of the effect of RA involves RA nuclear receptors, retinoylation (a posttranslational modification of proteins by RA) may be a new nongenomic mechanism by which RA acts on cells. An early event in RA-induced differentiation may be retinoylation of RII alpha (regulatory subunits of cAMP-dependent protein kinase), in which RII alpha units are retinoylated and the retinoylated RII alpha is then translocated to the nucleus. Drugs can also be combined with RA in RA-differentiation therapy. Cytodifferation therapy by RA in APL patients exhibits limitations due to the resistance of relapsed patients to further RA treatment. This may occur through the induction of expression of various genes that reduce RA blood concentrations. Treatment with combinations of RA and other agents may be one way to reduce induction of those genes. Good candidates for such agents include cAMP-elevating agents, retinoids, steroids, and fatty acids that synergistically induce differentiation of HL60 cells. Two derivatives of falconensone A, falconensone A p-bromophenylhydrazone, which has a bromophenyl residue, and falconensone A dioxime, which possesses a hydroxy residue, were synthesized to incorporate features of RA and N-[4-hydroxyphenyl] retinamide. Both derivatives have exhibited more potent biological activity than the parent falconensone A in vitro and in vivo.
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Affiliation(s)
- Noriko Takahashi
- Department of Health Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
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KRUSIUS FE, OKA M. Effect of long-term treatment with corticosteroids on adrenocortical function studies in rheumatoid arthritis in the light of the response of plasma-free and total 17,21-dihydroxy-20 ketosteroids to intravenous corticotropin. Ann Rheum Dis 2000; 17:184-8. [PMID: 13559937 PMCID: PMC1007032 DOI: 10.1136/ard.17.2.184] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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LINDNER F, JUNK R, NESEMANN G, SCHMIDT-THOME J. [Production of 20 beta-hydroxysteroids from 17 alpha, 21-dihydroxy-20- ketosteroids by microbiological hydration with Streptomyces hydrogenans]. ACTA ACUST UNITED AC 2000; 313:117-23. [PMID: 13620227 DOI: 10.1515/bchm2.1958.313.1.117] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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16
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17
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KOIDE SS, CHEN C, FREEMAN S. Inhibition of 3 alpha-hydroxysteroid-mediated transhydrogenase of rat-liver homogenate by Delta 4-3-oxosteroids. ACTA ACUST UNITED AC 1998; 38:374-5. [PMID: 14410581 DOI: 10.1016/0006-3002(60)91266-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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18
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19
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Kempfle M, Müller R, Palluk R, Zachariasse KA. Fluorescence of 3-keto-steroids in aqueous solution. Probes for steroid-protein interactions. Eur Biophys J 1986; 14:29-35. [PMID: 3816697 DOI: 10.1007/bf00260400] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The physiologically important 3-keto-steroids are non-fluorescent or only weakly fluorescent in protic as well as in aprotic solvents. In contrast, the 4,6,8(14)-triene-3-one steroids are highly fluorescent in aqueous solution but they do not appreciably fluoresce in other solvents. Evidence is presented that the introduction of double bonds into the skeleton of the 3-keto-steroids leads to a decrease of the energy of the lowest pi-pi* state, bringing this level into the neighbourhood of the non-fluorescent n-pi* state. As a consequence, for two states of approximately the same energy, relatively small perturbations such as those due to solvent interactions, protein binding and micelle formation, will then determine whether a system will fluoresce (pi-pi* state lowest) or not (n-pi* state lowest). When the fluorescent 3-keto-steroids, having three conjugated double bonds, bind to proteins, the fluorescence intensity becomes almost zero, making these compounds useful as probes for steroid-protein interactions. This quenching of the fluorescence is explained by a decrease in energy of the n-pi* state relative to the pi-pi* state of th steroids due to hydrophobic interactions with the proteins.
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Abstract
Affinity labelling techniques have proved indispensable for the study of reversible biological recognition systems, since they conserve ligand-receptor interaction by covalent linkage. Using photo- and electrophilic labelling, it has become possible to unequivocally identify steroid hormone receptors and their proteolytic degradation products and it is simple to establish receptor peptide maps even in crude receptor preparations. The isolation of receptor proteins has been greatly simplified, as their integrity can be analyzed at any step of a purification protocol by SDS-PAGE analysis after crosslinking. Moreover, affinity-labelled receptors can be purified under denaturing conditions, e.g., in high-resolving preparative SDS-PAGE, and the material obtained can be efficiently used to generate anti-receptor antibodies. Peptide mapping after crosslinking of related receptors has been used to assess the degree of structural homology between different forms of steroid hormone receptors and receptors of different species. Peptide sequence analysis of purified crosslinked receptor protein and anti-receptor antibodies have provided the basis for cloning corresponding genes. Techniques have been established to demonstrate--via crosslinking--that the cloned DNA sequences correspond to the receptor gene binding the correct ligand. The analytical and preparative crosslinking methods developed for steroid receptors are potentially important for the study of any system in which signal transduction proceeds via the reversible interaction between biological macromolecules.
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MESH Headings
- Affinity Labels/metabolism
- Animals
- Binding, Competitive
- Carrier Proteins/metabolism
- Cell Membrane/metabolism
- Chemical Phenomena
- Chemistry
- Chromatin/metabolism
- Cloning, Molecular
- Cross-Linking Reagents
- DNA/metabolism
- Humans
- Ketones
- Ketosteroids
- Molecular Weight
- Peptide Hydrolases/metabolism
- Photochemistry
- Promegestone/metabolism
- Receptors, Androgen/metabolism
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/isolation & purification
- Receptors, Cell Surface/metabolism
- Receptors, Estrogen/metabolism
- Receptors, Glucocorticoid/genetics
- Receptors, Glucocorticoid/metabolism
- Receptors, Progesterone/genetics
- Receptors, Progesterone/metabolism
- Tamoxifen/analogs & derivatives
- Tamoxifen/metabolism
- Ultraviolet Rays
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Abstract
Controlled alkaline hydrolysis of 16 alpha-bromo-17-keto steroids 1, 5 and 7 with potassium carbonate and tetra-n-butylammonium hydroxide (n-Bu4NOH) and synthesis of 2 alpha-hydroxy-3-ones 11, 13 and 16 by the controlled hydrolysis of the corresponding 2 alpha-bromo-3-ones 9, 12 and 15 are described. Treatment of the bromoketones 1,5 and 7 with potassium carbonate in aqueous acetone or with n-Bu4NOH in aqueous dimethylformamide (DMF) gave 16 alpha-hydroxy-17-ones 3m 6 and 8 in 85-90% yield, respectively. 2 alpha-Hydroxy-3-ones 11, 13 and 16 were obtained by hydrolysis of the corresponding bromoketones 9, 12 and 15 in high yields using the above conditions or sodium hydroxide in pyridine or DMF, respectively. Deuterium labeling experiments suggested that equilibration between the 2 alpha-bromoketone 9 and the 2 beta-bromo isomer 10 precedes the formation of the ketol 11 in which the true intermediate might be the 2 beta-isomer 10. However, rearranged androstane derivatives, 3 beta-hydroxy-2-one 18 and 20, were stereoselectively obtained by treatment of the bromoketones 12 and 15 with an excess amount of sodium hydroxide.
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Fishman J, Raju MS. Mechanism of estrogen biosynthesis. Stereochemistry of C-1 hydrogen elimination in the aromatization of 2 beta-hydroxy-19-oxoandrostenedione. J Biol Chem 1981; 256:4472-7. [PMID: 7012154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
19-Hydroxy[1 alpha-3H]androstenedione was synthesized and its specific activity was accurately determined. Upon aromatization of the above material by placental microsomal aromatase preparation, a process involving 1 beta hydrogen elimination, only 7.4% of the isotope was lost establishing the alpha orientation of the 3H at C-1 in the substrate. The 19-hydroxy[1 alpha]3H]androstenedione was used as the starting material in the synthesis of 2 beta-hydroxy-19-oxo[1 alpha-3H]androstenedione which therefore had the same specific activity and isotope orientation as its precursor. The nonenzymatic collapse of 2 beta-hydroxy-19-oxo[1 alpha-3H]androstenedione in pH 7.1 buffer to estrone was associated with the elimination of only 2.6% of the isotope indicating that this process proceeds also with stereospecific 1 beta hydrogen elimination. The stereochemistry of hydrogen loss in the nonenzymatic aromatization of the 2 beta-hydroxy-19-oxo derivative is therefore beta and identical with that of estrogen biosynthesis. This provides further evidence in support of the hypothesis that the final enzymatic hydroxylation of the aromatization sequence takes place at position 2 beta of the androgen substrate and that its product, the 2 beta-hydroxy-19-aldehyde, is the proximate precursor of estrogen with the final conversion occurring nonenzymatically.
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23
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Sehgal PK, Joseph KT, Chandrakasan G. Studies on collagen ketosteroids interactions. Indian J Biochem Biophys 1980; 17:233-6. [PMID: 7450810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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24
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Abstract
Two proteins in the rat, androgen binding protein (ABP) and the cytoplasmic receptor (CR), have high affinity and limited capacity for binding androgens. To determine the structural requirements for binding with high affinity, each protein was partially purified and the ability of over 100 steroids to compete with [3H]dihydrotestosterone (17 beta-hydroxy-5 alpha-androstan-3-one) for binding sites was assessed. The results indicate marked differences in the steroid specificities of the two proteins. Some alterations of dihydrotestosterone at C-2 or C-2 and C-3 increase binding to ABP two to four-fold. Similarly, the affinity of 17 beta-hydroxy-7 alpha-methyl-4-estren-3-one for ABP increases two-fold when a double bond is created at C-14. Addition of a methyl group in the alpha position at C-7 or C-17, or an ethinyl group at C-17 cause little change in affinity; however, modifications at C-11 and C-17 beta, and deletion of the methyl group at C-10 significantly impair binding to ABP. Binding to the CR is maintained or increased by deletion of the methyl group at C-10. Binding is lessened by modifications at C-3 and C-17 beta. Most alterations at C-2, C-7, C-11, and C-17 alpha have only minor effects on binding to the CR. These studies should provide a molecular basis for predicting the effects of specific structural modifications. When some modifications at C-2 or C-2 and C-3 are combined with changes at C-17 beta, the resulting steroids retain very high affinity for ABP and very limited binding to the CR. Such steroids may provide a means for assessing the function of ABP.
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25
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Tsitsa P, Tsatsas G, Sandris C. Synthesis and reduction of steroid C-20 alkylidene cyanoacetates. Steroids 1979; 33:23-31. [PMID: 452059 DOI: 10.1016/s0039-128x(79)80003-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The geometry of the condensation products between ethyl cyanoacetate and 20-ketosteroids (5 alpha-pregnane-20-one, 3 beta-hydroxypregn-5-en-20-one and 3 beta-acetoxypregn-5-en-20-one) was established by NMR spectra. Reduction of these steroid C-20 alkylidene cyanoacetates was shown to afford one of the two possible 20-C epimers, which seen to correspond to the 20 beta-methyl configuration.
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26
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Atrat P, Deppmeyer V, Hörhold C, Möller L, Knöll R. [Steroid converting enzymes from microorganisms. VIII. Effect of the organic solvent specific hydrophobicity of the binding on the affinity-matrix- affinity chromatography of a 4-en-3-oxo-steroid: (Acceptor)-1-en-oxidoreductase from Nocardia opaca]. J Steroid Biochem 1978; 9:691-4. [PMID: 692134 DOI: 10.1016/0022-4731(78)90183-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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27
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Atrat P, Deppmeyer V, Hörhold C. [Steroid metabolizing enzymes from microorganisms. VII. The nature of the biospecific binding to an affinity matrix-affinity chromatography of 4-en-3-oxo-steroid: (acceptor)-1-en-oxidoreductase from Nocardia opaca]. J Steroid Biochem 1978; 9:579-82. [PMID: 692123 DOI: 10.1016/0022-4731(78)90125-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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28
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Lestrovaja NN, Dänhardt S, Hörhold C. [Steroid transforming enzymes from microorganisms. V. Purification of a 4-en-3-oxosteroid: (acceptor)-1-en-oxidoreductase from Nocardia opaca and characterization of the prosthetic group]. Z Allg Mikrobiol 1978; 18:189-96. [PMID: 695702 DOI: 10.1002/jobm.3630180306] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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29
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Meagher RB. Purification and partial amino acid sequence of the cyanogen bromide fragments of muconolactone isomerase from Pseudomonas putida. Biochim Biophys Acta 1977; 494:33-47. [PMID: 901811 DOI: 10.1016/0005-2795(77)90132-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Muconolactone isomerase is shown to be resistant to proteolytic cleavage by trypsin. Cyanogen bromide cleavage at the methionine residues of the polypeptide is at least 95% complete. Six cyanogen bromide fragments are separated on DEAE-cellulose. One fragment is shown by amino acid analysis and carboxyl-terminal analysis to be an incomplete cleavage product. The five remaining fragments represent the entire polypeptide and have been ordered with respect to the entire muconolactone isomerase sequence. Approximately 50% of the polypeptide sequence could be determined from these fragments by the dansyl-Edman technique. The possible evolutionarily homologous origins of muconolactone isomerase and two analogous isomerases, carboxymuconolactone decarboxylase and sigma5-3-ketosteroid isomerase, are discussed.
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30
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Atrat P, Deppmeyer V, Gabert A, Flemming C, Hörhold C. [Steroid conjugating enzyme from microorganisms. VI. Purification of 4-en-o-oxosteroid: (acceptor)-1-en-oxidoreductase from Nocardia opaca by affinity chromatography]. J Steroid Biochem 1977; 8:1017-24. [PMID: 916673 DOI: 10.1016/0022-4731(77)90201-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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31
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Eckstein B, Nimrod A. Properties of microsomal delta4-3-ketosteroid 5alpha-reductase in immature rat ovary. Inhibition by estradiol-17beta. Biochim Biophys Acta 1977; 499:1-9. [PMID: 889890 DOI: 10.1016/0304-4165(77)90222-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The subcellular distribution of immature rat ovarian 5alpha-reductase has been studied by utilizing 20alpha-hydroxypregn-4-en-3-one as substrate. The main enzyme activity was found to be associated with the microsomal fraction, with lower activities in the 1000 X g and 10 000 X g fractions. The enzyme activity associated with the microsomes exhibited an apparent Km of 3.0 +/- 1.1 micrometer for 20alpha-hydroxypregn-4-en-3-one and 36.3 +/- 6.7 micrometer for testosterone as substrate. Progesterone and testosterone competitively inhibited the 5alpha-reduction of 20alpha-hydroxypregn-4-en-3-one; estradiol-17beta was found to be a noncompetitive inhibitor of this reaction. A concentration of estradiol-17beta as low as 1 micrometer when added to 25 micrometer concentration of 20alpha-hydroxypregn-4-en-3-one exerted a significant inhibition of 5alpha-reductase activity.
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32
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Lestrovaja NN, Groh H, Hörhold C, Dänhardt S, Schubert K. Steroid transforming enzymes from microorganisms. IV. Purification and cofactor requirement of the 4-ene-3-oxosteroid-5alpha-reductase from Mycobacterium smegmatis. J Steroid Biochem 1977; 8:313-7. [PMID: 18639 DOI: 10.1016/0022-4731(77)90026-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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33
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Chang HL, Cimarusti CM, Diassi PA, Grabowich P. Influence of a 9alpha-fluorine on the epoxidation of an 11beta-hyroxy-delta4-3-keto steroid with basic hydrogen peroxide. J Org Chem 1977; 42:358-9. [PMID: 830869 DOI: 10.1021/jo00422a046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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34
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Shimizu Y. Mass spectral fragmentation of 18-norsteroids and 12-oxo-20-hydroxysteroids. Steroids 1976; 28:159-78. [PMID: 973233 DOI: 10.1016/0039-128x(76)90107-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Comparison of the mass spectra of 18-norsteroids with those of the corresponding normal steroids revealed that the absence of the 18-methyl group has little effect on the fragmentation pattern, especially on the D-ring and side-chain cleavage. The results indicate that the stability-of the cation or radical species, due to the quarternary nature of C-13, is not a major driving force in the key 13-17 cleavage. Hydrogen transfer observed in the D-ring fragmentation of 20-hydroxy-18-nor-5 alpha-pregnan-13-ones was not found to be specific to the 18-norcompounds. Deuterium labeling at the 20-OH and 20 alpha-H has suggested the involvement of a unique triple hydrogen rearrangement in this major cleavage. Migration of the 20-hydrogen to the 12-keto oxygen was also observed in the fragmentation of dammarane derivatives and was likewise confirmed by deuterium labeling.
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Nakajima S, Konaka R, Takeda K. [Oxidation of 2- and 3-oxo-steroids. II. Oxidation of 3-oxo-steroids with oxygen in basic solution (author's transl)]. YAKUGAKU ZASSHI 1976; 96:863-79. [PMID: 184269 DOI: 10.1248/yakushi1947.96.7_863] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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36
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Tomita T, Saito K, Takakuwa E. [Steroid 5beta-reductase activity in the livers of rats administered with lead acetate (author's transl)]. Nihon Eiseigaku Zasshi 1976; 31:361-6. [PMID: 987416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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37
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Nakajima S, Konaka R, Takeda K. [Oxidation of 2- and 3-oxo-steroids. I. Oxidation of 2-oxo-steroids with oxygen in basic solution (author's transl)]. YAKUGAKU ZASSHI 1976; 96:764-76. [PMID: 987212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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38
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Pradhan SK, Radhakrishnan TV, Subramanian R. A study of the Stork reductive cyclization of steroidal acetylenic ketones in aprotic media with the naphthalene anion radicals. J Org Chem 1976; 41:1943-52. [PMID: 1262997 DOI: 10.1021/jo00873a012] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Lewbart ML. Reactions of alpha-ketols and other 21-hydroxy steroids with phosgene. IV. Formation of 20-chloro-17,20-cyclic carbonates from 17 alpha-hydroxy-20-ones. J Org Chem 1976; 41:78-84. [PMID: 1244460 DOI: 10.1021/jo00863a017] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Vilkov I, Dokumov S, Spasov S, Genkova P. [Cytogenetic studies of patients with primary amenorrhea]. Akush Ginekol (Mosk) 1975:10-3. [PMID: 1240727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Abstract
A method is described to determine the mass of 7alpha-hydroxy cholesterol synthetized in vitro by liver microsomes without the use of a radioactive substrate.
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Steele PA, Flint AP, Turnbull AC. Proceedings: Evidence of steroid C17, 20 lyase activity in ovine foeto-placental tissue. J Endocrinol 1975; 64:41P. [PMID: 1133527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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49
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Martyr RJ, Benisek WF. Chemical modification of amino acid residues associated with the delta-4-3-ketosteroid-dependent photoinactivation of delta-5-3-ketosteroid isomerase. J Biol Chem 1975; 250:1218-22. [PMID: 1167545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The photoinactivation of the Δ (5)-3-ketosteroid isomerase of Pseudomonas testosteroni in the presence of 3-oxo-4-estren-17β-yl acetate and air is accompanied by destruction of histidine and aspartate (or asparagine). The first order rate constant of photoinactivation of the enzyme is equal, within experimental error, to the first order rate constant for the destruction of a single aspartate (or asparagine) residue and is considerably greater than the first order rate constant for the destruction of a single residue of histidine. When the photolysis is carried out under anaerobic conditions, only aspartic acid (or asparagine) is destroyed as enzyme is inactivated. Both inactivation and aspartate (or asparagine) destruction occur to a greater extent in the absence of oxygen than in its presence. The destruction of histidine, on the other hand, is found to be strictly oxygen-dependent. These results suggest that photochemical modification of a single residue of aspartate (or asparagine) is largely, if not entirely, responsible for photoinactivation of the enzyme under these conditions. When irradiated in the presence of 3-oxo-4-entren-17β-yl acetate, performic acid-oxidized bovine pancreatic ribonuclease does not suffer any detectable destruction of its aspartic or asparaginyl residues but does undergo significant destruction of its histidine residues. These observations suggest that the aspartate (or asparagine) residue modification found with isomerase is an active site-directed photochemical reaction, whereas the modification of histidine may not be.
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50
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Vandenheuvel FA. Gas-liquid chromatographic studies of reactions and structural relationships of steroids. II. Positions 3, 11, and 20 in the pregnane series. J Chromatogr A 1975; 103:113-34. [PMID: 1117033 DOI: 10.1016/s0021-9673(00)83806-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Qualitative and quantitative effects of classical reactions on steroids observed by gas-liquid chromatography (GLC) under standardized conditions, including the double internal standard technique, are reported. Simple procedures applicable to nanogram amounts of reactants which afford excellent yields of the major products are described. Reactions studied include the Wolff-Kishner removal of keto groups (WK), their conversion to hydroxyl groups by NaBH4(RD), and to dioxolone derivatives by ethylene glycol (DO); the conversion of hydroxyl to keto groups by CrO3 (OX), and to TMS ethers by hexamethyldisilazane; the hydrolysis of dioxolone and TMS derivatives by H+ (HY). GLC chromatograms of reaction mixtures of single and multistep reactions readily provide information on effects on functional groups at positions 3, 11, and 20 in the pregnane series, and the retention times of many steroids unavailable from commercial or other sources. GLC data analysis provides relationships between steroid structure and retention time from which methods for the computation of retention times and for steroid identification are designed. The accuracy of the computation methods is demonstrated.
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