Hydroxysteroid dehydrogenase

About: Hydroxysteroid dehydrogenase is a research topic. Over the lifetime, 1087 publications have been published within this topic receiving 28468 citations. The topic is also known as: hydroxysteroid dehydrogenase.

Method for efficiently producing hydroxysteroid dehydrogenase with testosterone comamonas

Abstract: The invention relates to a method for efficiently producing hydroxysteroid dehydrogenase with testosterone comamonas. The method comprises steps of bacteria culture, seeding tank culture, fermentation tank culture and the like, and can produce hydroxysteroid dehydrogenase efficiently. The hydroxysteroid dehydrogenase has remarkable effects on crops in preventing disease, promoting growth and increasing yield. Furthermore, if being used as a novel fodder enzyme preparation in cultivation in stock farming, the hydroxysteroid dehydrogenase can effectively promote pigs and broiler chickens to grow, improves the laying rate of laying hens, reduces disease of beasts and birds, and has obvious effect in promoting growth. According to the method, viable bacteria in per milliliter of fermentation liquor is improved to be 30 billion from 0.1 billion, the enzyme activity in per gram of dry powder is improved to be 300 thousand from 1 thousand, so that the product cost is greatly lowered, and the method can be used for industrial production.

Congenital Adrenal Hyperplasia (CAH): Definition and Enzymatic Defects in Various Forms

Abstract: Congenital adrenal hyperplasia (CAH) is a group of disorders characterized by enzymatic defects in cortisol biosynthesis. Steroidogenic enzymes can mainly be divided into two groups: cytochrome P450 (CYP) and hydroxysteroid dehydrogenases/ketosteroid reductase (HSDs/KSR). The CYP enzyme group can metabolize more than one substrate and is involved in multiple steps of steroidogenesis. These enzymes have unidirectional function, catalyzing irreversibly the reactions they involved, and have no feedback from downstream precursors. The HSD enzymes catalyze reversible reactions, they modulate the steroid flux in the reductive or oxidative mode. Based on their activity, HSD enzymes are classified into dehydrogenases which oxidate hydroxysteroids to ketosteroids and reductases which reduce ketosteroids to hydroxysteroids. Due to mutations on these enzymes, one or more of the glucocorticoid, mineralocorticoid, and androgen biosynthesis pathways are affected. In all types of CAH, low cortisol production stimulate the secretion of corticotrophin releasing hormone (CRH) and adrenocorticotrophic hormone (ACTH) which leads to adrenal hyperplasia and eventually accumulation of steroid hormone precursors and usually hyperandrogenemia. The most common two forms are CYP21A2 (21-hydroxylase, 95% of cases) and CYP11B1 (11-beta hydroxylase, 5–8% of cases) deficiencies. Rare forms of CAH including 17-alpha hydroxylase and 3-beta hydroxysteroid dehydrogenase type 2 also affect gonadal steroid biosynthesis. Steroidogenic acute regulatory protein (StAR) deficiency and side chain cleavage enzyme deficiencies have similar clinical and laboratory characteristics except having lipoid accumulation in the former. P450 oxydoreductase deficiency is the most complicated form of CAH, and the clinical picture is a combination of 17-alpha hydroxylase and 21-hydroxylase deficiency.

New 7ß-hydroxy steroid dehydrogenases and their use

Abstract: 7-beta -hydroxysteroid dehydrogenase (7beta -HSDH) and its derived functional equivalents, obtainable from bacterium, preferably Collinsella aerofaciensstrain DSM 3979 (ATCC 25986), are claimed. Independent claims are also included for: (1) a 7-beta -HSDH with an amino acid sequence having 263 amino acid residues (SEQ ID NO: 2) or its derived sequence with a degree of identity of at least 80% to the sequence of SEQ ID NO: 2; (2) enzymatic synthesis of 7-beta -hydroxysteroids, comprises reacting the corresponding 7-keto steroids in presence of the 7-beta -HSDH, and optionally isolating at least one reduction product, from the reaction preparation; (3) enzymatic oxidation of 7-beta -hydroxysteroids, comprises reacting the 7-beta -hydroxysteroids in presence of 7-beta -hydroxysteroid dehydrogenase, and optionally isolating the formed oxidation product, from the reaction preparation; and (4) preparing ursodeoxycholic acid derivative of formula (I), comprising (a) optionally chemically oxidizing cholic acid derivative of formula (II) to dehydrocholic acid derivative of formula (III), (b) reducing (III) in presence of at least one 7-beta -HSDH, to 3,12-diketo-7-beta -cholanic acid derivative of formula (IV), (c) reducing (IV) in presence of at least one 3-alpha -hydroxysteroid dehydrogenase (3-alpha -HSDH) to corresponding 12-keto-ursodeoxycholic acid derivative of formula (V), (d) chemically reducing (V) to (I), and (e) optionally further purifying the reaction product. R : alkyl, NR 1>R 2>, H, alkali metal ion or N(R 3>) 4+>; R 3> : H or alkyl; and R 1>, R 2> : not defined. [Image] [Image] [Image].