Progesterone hydroxylation

Swinney, D. C., Ryan, D, E., Thomas, E E., and Levin, W. (1987). Regioselective Progesterone Hydroxylation Catalyzed by Eleven Rat Hepatic Cytochrome P-450 Isozymes, BiodKmistiy, 26 7073-7083. 

Cortisol is synthesized from pregnenolone by two pathways in the fasciculata and reticularis zones of the adrenal gland. For simplicity, only one pathway is shown in Figure 51-6. The enzyme 17a-hydroxylase and the enzyme complex A -3P-hydroxysteroid dehydrogenase A ketosteroid isomerase located in the endoplasmic reticulum will synthesize 17a-hydroxyprogesterone from either 17a-hydroxypregnenolone or progesterone. Hydroxylation of this compound by the... 

A recent departure has been motivated by the need for unusual products which may be sterol metabolites. Studies have been directed to the biosynthesis, for example, of the otherwise rare and inaccessible derivatives of progesterone hydroxylated at the 6-, 9-, 14-, or 15-positions that could be accomplished by incubating progesterone in a complex medium with the fungus Apiocrea chrysosperma (Smith et al. 1988). The hydroxylation of progesterone and closely related compounds at the 150-position by cell extracts of Bacillus megaterium has been noted in Section 4.4.1.2. 

E.F. Johnson (1988). Selective inactivation by 21-chlorinated steroids of rabbit liver and adrenal microsomal cytochromes P-450 involved in progesterone hydroxylation. Arch. Biochem. Biophys. 264,462 71. 

Swinney, D.C., D.E. Ryan, P.E. Thomas, and W. Levin (1987). Regioselective progesterone hydroxylation catalyzed by eleven rat hepatic cytochrome P-450 isozymes. Biochemistry 26, 7073-7083. 

C21H36O2. M,p. 238°C. There are four isomeric pregnane-3,20-diols differing only in the orientation of the hydroxyl groups at positions 3 and 20 and with the 5/ configuration. Only the 3a,20a occurs naturally. It is formed by reduction of progesterone in the liver and is the chief urinary metabolite of it, being... 

Pregnenolone is transported from the mitochondria to the ER, where a hydroxyl oxidation and migration of the double bond yield progesterone. Pregnenolone synthesis in the adrenal cortex is activated by adrenocorticotropic hormone (ACTH), a peptide of 39 amino acid residues secreted by the anterior pituitary gland. 

After the initial growth, progesterone (05-5 g l"1) is added as a powder or as an acetone solution. If a powdered form is used, it is wetted with a small amount (0.01%) of Tween to facilitate its dissolution into the reaction mixture. A single addition of progesterone at a concentration of about 5g T1 enables about 86% hydroxylation to take place within about 50h. The remaining progesterone remains unaltered. 

Alternatively, hydroxylation may be carried out in a continuous process. In this the organism is first cultured in one vessel and then transferred to a production vessel. Progesterone is fed into this second vessel at a concentration of 05g l1. Over 50% of the progesterone is hydroxylated when the residence time in the production vessel is about 5h. 

A single crystallisation is unlikely to lead to the isolation of pure crystals. In practice the product recovered in this process contains about 90% 11 a-hydroxyprogeterone with low levels of other products (especially 5 a-pregnane-3,20-dione and 60, lla-dihydroxyprogesterone). An example of a manufacturer who uses microbial 11a hydroxylation is Upjohn progesterone is used as substrate. 

You should have identified this reaction as an 11 a-hydroxylation. The most commonly used organism to carry out lla-hydrolylations is Rhizopus nigrum. The substrate in this case is progesterone. 

Hydroxylation of progesterone and closely related compounds at the 15-(3 position by cell extracts of Bacillus megaterium (Berg et al. 1976). 

Breskvar K, T Hudnik-Plevnik (1977) A possible role of cytochrome P-450 in hydroxylation of progesterone by Rhizopus nigricans. Biochem Biophys Res Comm 74 1192-1198. 

Figure 14.8 Microbial hydroxylation of progesterone to 11-a-OH-progesterone by Rhizopus sp.

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