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Journal of Biochemistry Mar 1986A steroid monooxygenase of Cylindrocarpon radicicola was found to catalyze oxygenative lactonization of 17-ketosteroid, androstenedione, to yield D-homo-17...
A steroid monooxygenase of Cylindrocarpon radicicola was found to catalyze oxygenative lactonization of 17-ketosteroid, androstenedione, to yield D-homo-17 alpha-oxasteroid, testololactone, i.e., the androstenedione monooxygenase reaction, in addition to catalyzing the progesterone monooxygenase reaction. The reaction product was identified by TLC, GLC, and mass spectrometry. The oxygenation proceeded with unitary stoichiometry for 17-ketosteroid, NADPH, and molecular oxygen, indicating that it is a typical monooxygenase reaction of the external electron donor type. The enzyme catalyzed successively the side chain cleavage reaction of 17 alpha-hydroxy-20-ketosteroid to produce its 17-keto derivative and the lactonization of the product. The effects of pH and of the concentration of substrate steroids on the androstenedione monooxygenase reaction were different from those on the progesterone monooxygenase reaction. Progesterone is a strong and competitive inhibitor of the lactonization of 17-ketosteroids. The steroid monooxygenase is concluded to have the activities of both oxygenative esterification of 20-ketosteroids and oxygenative lactonization of 17-ketosteroids.
Topics: Androstenedione; Hydrogen-Ion Concentration; Kinetics; Mitosporic Fungi; NADP; Oxidation-Reduction; Pregnenolone; Progesterone; Steroid 17-alpha-Hydroxylase; Steroid Hydroxylases; Testolactone
PubMed: 3486864
DOI: 10.1093/oxfordjournals.jbchem.a135542 -
The Journal of Cell Biology Aug 1975Exposure of CHO-K1 cells in vitro to dibutyryl adenosine cyclic 3',5'-monophosphate (DBcAMP) plus testololactone produces a rapid, reversible antagonism of...
Exposure of CHO-K1 cells in vitro to dibutyryl adenosine cyclic 3',5'-monophosphate (DBcAMP) plus testololactone produces a rapid, reversible antagonism of ligand-induced collection of initially dispersed concanavalin A (Con A) binding sites into a caplike mass. Morphologically, as Con A capping occurs, the cells become less spread and then round completely. With prolonged Con A exposure, cells cultured in either the absence or the presence of DBcAMP plus testololactone cap and round. Capping is blocked by cold treatment and respiratory inhibitors. Colcemid at concentrations greater than 1 muM promotes both Con A capping and cell rounding. Cytochalasin B at similar concentrations inhibits both capping and cell rounding. Treatment of cells with Con A has little effect on intracellular cAMP concentration. Possible mechanisms by which cAMP may modulate the movement of Con A binding sites are discussed.
Topics: Animals; Azides; Binding Sites, Antibody; Bucladesine; Cell Line; Colchicine; Cold Temperature; Concanavalin A; Cricetinae; Cytochalasin B; Drug Antagonism; Female; Fluoresceins; Iodoacetates; Microscopy, Electron; Ovary; Testolactone; Theophylline
PubMed: 167034
DOI: 10.1083/jcb.66.2.392 -
Hormones (Athens, Greece) 2006The McCune-Albright Syndrome (MAS) is a sporadic rare disease first described in 1936 by McCune and separately by Albright. MAS is characterized by a triad of physical...
The McCune-Albright Syndrome (MAS) is a sporadic rare disease first described in 1936 by McCune and separately by Albright. MAS is characterized by a triad of physical signs: café-au-lait spots, polyostotic fibrous dysplasia and autonomous endocrine hyperfunction. MAS is predominantly observed in girls and is rarely reported in males. We report the case of a 9-year old boy with gonadotropin independent precocious puberty, café-au-lait spots, polyostotic fibrous dysplasia and growth hormone hypersecretion.
Topics: Adenoma; Child; Facial Bones; Fibrous Dysplasia, Polyostotic; Glucagon; Glucose Tolerance Test; Gonadotropin-Releasing Hormone; Growth Hormone-Secreting Pituitary Adenoma; Humans; Male; Puberty, Precocious; Radionuclide Imaging; Skin Pigmentation; Somatostatin; Testolactone
PubMed: 16950755
DOI: 10.14310/horm.2002.11186 -
Fertility and Sterility Jul 1994Severe ovarian hyperstimulation syndrome occurred after the administration of LA to suppress multicystic ovaries. It is possible that this patient with multiple ovarian...
Severe ovarian hyperstimulation syndrome occurred after the administration of LA to suppress multicystic ovaries. It is possible that this patient with multiple ovarian cysts, each 2 to 3 cm in size, is at increased risk for a paradoxical stimulatory rather than inhibitory response to GnRH-a.
Topics: Adult; Estradiol; Female; Humans; Leuprolide; Ovarian Hyperstimulation Syndrome; Polycystic Ovary Syndrome; Testolactone
PubMed: 8005289
DOI: 10.1016/s0015-0282(16)56839-3 -
The Journal of Cell Biology Jul 1974
Comparative Study
Topics: Azides; Bucladesine; Cell Line; Cell Survival; Cell Transformation, Neoplastic; Clone Cells; Concanavalin A; Cyanides; Female; Fluorides; Glycolysis; Iodine Radioisotopes; Iodoacetates; Kinetics; Ovary; Oxidative Phosphorylation; Receptors, Drug; Testolactone; Time Factors
PubMed: 4366107
DOI: 10.1083/jcb.62.1.247 -
The Journal of Biological Chemistry Oct 1961
Topics: Hormones; Lactones; Testolactone
PubMed: 14493683
DOI: No ID Found -
Blood Nov 1972
Comparative Study
Topics: Adult; Aged; Blood Cell Count; Blood Platelets; Breast Neoplasms; Erythrocytes; Female; Hematocrit; Humans; Middle Aged; Testolactone; Testosterone
PubMed: 5078927
DOI: No ID Found