6B82

Zebra Fish CYP-450 17A1 Mutant Abiraterone Complex

Summary for 6B82

• Entry DOI: 10.2210/pdb6b82/pdb
• Descriptor: Cytochrome P450, family 17, subfamily A, polypeptide 1, PROTOPORPHYRIN IX CONTAINING FE, Abiraterone, ... (6 entities in total)
• Functional Keywords: cytochrome p450, cyp17a1 mutant, p450 17a1, monooxygenase, 17a-hydroxylase, heme protein, cytochrome p450 oxidoreductase, abiraterone, 17a-hydroxylation, membrane, microsome, endoplasmic reticulum, oxidoreductase
• Biological source: Danio rerio (Zebrafish)
• Total number of polymer chains: 2
• Total formula weight: 117146.05

Authors

Pallan, P.S.,Egli, M. (deposition date: 2017-10-05, release date: 2017-12-13, Last modification date: 2024-10-09)

Primary citation

Gonzalez, E.,Johnson, K.M.,Pallan, P.S.,Phan, T.T.N.,Zhang, W.,Lei, L.,Wawrzak, Z.,Yoshimoto, F.K.,Egli, M.,Guengerich, F.P.
Inherent steroid 17 alpha ,20-lyase activity in defunct cytochrome P450 17A enzymes.
J. Biol. Chem., 293:541-556, 2018

PubMed Abstract: Cytochrome P450 (P450) 17A1 catalyzes the oxidations of progesterone and pregnenolone and is the major source of androgens. The enzyme catalyzes both 17α-hydroxylation and a subsequent 17α,20-lyase reaction, and several mechanisms have been proposed for the latter step. Zebrafish P450 17A2 catalyzes only the 17α-hydroxylations. We previously reported high similarity of the crystal structures of zebrafish P450 17A1 and 17A2 and human P450 17A1. Five residues near the heme, which differed, were changed. We also crystallized this five-residue zebrafish P450 17A1 mutant, and the active site still resembled the structure in the other proteins, with some important differences. These P450 17A1 and 17A2 mutants had catalytic profiles more similar to each other than did the wildtype proteins. Docking with these structures can explain several minor products, which require multiple enzyme conformations. The 17α-hydroperoxy (OOH) derivatives of the steroids were used as oxygen surrogates. Human P450 17A1 and zebrafish P450s 17A1 and P450 17A2 readily converted these to the lyase products in the absence of other proteins or cofactors (with catalytically competent kinetics) plus hydroxylated 17α-hydroxysteroids. The 17α-OOH results indicate that a "Compound I" (FeO) intermediate is capable of formation and can be used to rationalize the products. We conclude that zebrafish P450 17A2 is capable of lyase activity with the 17α-OOH steroids because it can achieve an appropriate conformation for lyase catalysis in this system that is precluded in the conventional reaction.

PubMed: 29212707
DOI: 10.1074/jbc.RA117.000504

Experimental method

X-RAY DIFFRACTION (3.03 Å)