The sulfuryl transfer mechanism. Crystal structure of a vanadate complex of estrogen sulfotransferase and mutational analysis.
Estrogen sulfotransferase (EST) catalyzes transfer of the 5'-sulfuryl group of adenosine 3'-phosphate 5'-phosphosulfate (PAPS) to the 3alpha-phenol group of estrogenic steroids such as estradiol (E2). The recent crystal structure of EST-adenosine 3', 5'-diphosphate (PAP)- E2 complex has revealed that residues Lys48, Thr45, Thr51, Thr52, Lys106, His108, and Try240 are in position to play a catalytic role in the sulfuryl transfer reaction of EST (Kakuta Y., Pedersen, L. G., Carter, C. W., Negishi, M., and Pedersen, L. C. (1997) Nat. Struct. Biol. 4, 904-908). Mutation of Lys48, Lys106, or His108 nearly abolishes EST activity, indicating that they play a critical role in catalysis. A present 2.2-A resolution structure of EST-PAP-vanadate complex indicates that the vanadate molecule adopts a trigonal bipyramidal geometry with its equatorial oxygens coordinated to these three residues. The apical positions of the vanadate molecule are occupied by a terminal oxygen of the 5'-phosphate of PAP (2.1 A) and a possible water molecule (2. 3 A). This water molecule superimposes well to the 3alpha-phenol group of E2 in the crystal structure of the EST.PAP.E2 complex. These structures are characteristic of the transition state for an in-line sulfuryl transfer reaction from PAPS to E2. Moreover, residues Lys48, Lys106, and His108 are found to be coordinated with the vanadate molecule at the transition state of EST.
Kakuta
Y
Y
Pharmacogenetics Section, Laboratory of Reproductive and Developmental Toxicology, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
Petrotchenko
E V
EV
Pedersen
L C
LC
Negishi
M
M
D000244:Adenosine Diphosphate / Q000737:chemistry*; D000818:Animals; D020134:Catalytic Domain / Q000235:genetics; D003461:Crystallography; D004252:DNA Mutational Analysis; D051379:Mice; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D015238:Sulfotransferases / Q000737:chemistry* / Q000235:genetics; D017356:Synchrotrons; D014638:Vanadates / Q000737:chemistry*
D014638:Vanadates; D000244:Adenosine Diphosphate; C010840:adenosine 3'-phosphate-5'-phosphate; D015238:Sulfotransferases; C020122:estrone sulfotransferase