DB code: S00310

RLCP classification	3.203.800.83 : Transfer
CATH domain	3.40.50.300 : Rossmann fold	Catalytic domain
E.C.	2.8.2.4
CSA	1hy3
M-CSA	1hy3
MACiE	M0154

CATH domain	Related DB codes (homologues)
3.40.50.300 : Rossmann fold	S00527 S00547 S00548 S00550 S00554 S00555 S00671 S00672 S00676 S00680 S00682 S00913 S00914 S00301 S00302 S00303 S00304 S00307 S00308 S00305 S00306 S00309 S00311 M00114 M00199 D00129 D00130 D00540 M00186

Uniprot Enzyme Name
UniprotKB	Protein name	Synonyms	Pfam	RefSeq
P49891	Estrogen sulfotransferase, testis isoform	EC 2.8.2.4 Sulfotransferase, estrogen-preferring	PF00685 (Sulfotransfer_1) [Graphical View]
P49888	Estrogen sulfotransferase	EC 2.8.2.4 Sulfotransferase, estrogen-preferring EST-1	PF00685 (Sulfotransfer_1) [Graphical View]	NP_005411.1 (Protein) NM_005420.2 (DNA/RNA sequence)

KEGG enzyme name
estrone sulfotransferase 3'-phosphoadenylyl sulfate-estrone 3-sulfotransferase estrogen sulfotransferase estrogen sulphotransferase oestrogen sulphotransferase 3'-phosphoadenylylsulfate:oestrone sulfotransferase

UniprotKB: Accession Number	Entry name	Activity	Subunit	Subcellular location	Cofactor
P49891	ST1E1_MOUSE	3''-phosphoadenylyl sulfate + estrone = adenosine 3'',5''-bisphosphate + estrone 3-sulfate.	Homodimer (By similarity).	Cytoplasm.
P49888	ST1E1_HUMAN	3''-phosphoadenylyl sulfate + estrone = adenosine 3'',5''-bisphosphate + estrone 3-sulfate.	Homodimer.	Cytoplasm.

KEGG Pathways
Map code	Pathways	E.C.
MAP00150	Androgen and estrogen metabolism
MAP00920	Sulfur metabolism

Compound table
	Substrates		Products		Intermediates
KEGG-id	C00053	C00468	C00054	C02538
E.C.
Compound	3'-Phosphoadenylylsulfate	Estrone	Adenosine 3',5'-bisphosphate	Estrone 3-sulfate
Type	amine group,nucleotide ,sulfate group	aromatic ring (only carbon atom),carbohydrate,steroid	amine group,nucleotide	aromatic ring (only carbon atom),carbohydrate,steroid,sulfate group
ChEBI	17980 17980	17263 17263	17985 17985	17474 17474
PubChem	10214 10214	5870 5870	159296 159296	3001028 3001028

1aquA	Unbound	Analogue:EST	Bound:A3P	Unbound	Unbound
1aquB	Unbound	Analogue:EST	Bound:A3P	Unbound	Unbound
1aqyA	Unbound	Unbound	Bound:A3P	Unbound	Unbound
1aqyB	Unbound	Unbound	Bound:A3P	Unbound	Unbound
1bo6A	Unbound	Unbound	Bound:A3P	Unbound	Transtion-state-analogue:A3P-VO4
1bo6B	Unbound	Unbound	Bound:A3P	Unbound	Transtion-state-analogue:A3P-VO4
1hy3A	Bound:PPS	Unbound	Unbound	Unbound	Unbound
1hy3B	Bound:PPS	Unbound	Unbound	Unbound	Unbound

Reference for Active-site residues
resource	references	E.C.
literature [1],[4]

Active-site residues
PDB	Catalytic residues	Cofactor-binding residues	Modified residues	Main-chain involved in catalysis	Comment

1aquA	LYS 48;LYS 106;HIS 108;SER 138
1aquB	LYS 48;LYS 106;HIS 108;SER 138
1aqyA	LYS 48;LYS 106;HIS 108;SER 138
1aqyB	LYS 48;LYS 106;HIS 108;SER 138
1bo6A	LYS 48;LYS 106;HIS 108;SER 138
1bo6B	LYS 48;LYS 106;HIS 108;SER 138
1hy3A	LYS 47;LYS 105;HIS 107;SER 137
1hy3B	LYS 47;LYS 105;HIS 107;SER 137

References for Catalytic Mechanism
References	Sections	No. of steps in catalysis
[1]	p.906-907
[2]	Fig.4, p.27327-27329	2
[4]	Fig.4, p.152-154	2
[5]	Fig.5, p.17931	2

References
[1]
Resource
Comments
Medline ID
PubMed ID	9360604
Journal	Nat Struct Biol
Year	1997
Volume	4
Pages	904-8
Authors	Kakuta Y, Pedersen LG, Carter CW, Negishi M, Pedersen LC
Title	Crystal structure of estrogen sulphotransferase.
Related PDB	1aqu 1aqy 1bo6
Related UniProtKB	P49891
[2]
Resource
Comments
Medline ID
PubMed ID	9765259
Journal	J Biol Chem
Year	1998
Volume	273
Pages	27325-30
Authors	Kakuta Y, Petrotchenko EV, Pedersen LC, Negishi M
Title	The sulfuryl transfer mechanism. Crystal structure of a vanadate complex of estrogen sulfotransferase and mutational analysis.
Related PDB
Related UniProtKB
[3]
Resource
Comments
Medline ID
PubMed ID	9556564
Journal	J Biol Chem
Year	1998
Volume	273
Pages	10888-92
Authors	Zhang H, Varlamova O, Vargas FM, Falany CN, Leyh TS, Varmalova O
Title	Sulfuryl transfer: the catalytic mechanism of human estrogen sulfotransferase.
Related PDB
Related UniProtKB
[4]
Resource
Comments	Review
Medline ID
PubMed ID
Journal	Arch Biochem Biophys
Year	2001
Volume	390
Pages	149-57
Authors	Negishi M, Pedersen LG, Petrotchenko E, Shevtsov S, Gorokhov A, Kakuta Y, Pedersen LC
Title	Structure and function of sulfotransferases.
Related PDB
Related UniProtKB
[5]
Resource
Comments
Medline ID
PubMed ID	11884392
Journal	J Biol Chem
Year	2002
Volume	277
Pages	17928-32
Authors	Pedersen LC, Petrotchenko E, Shevtsov S, Negishi M
Title	Crystal structure of the human estrogen sulfotransferase-PAPS complex: evidence for catalytic role of Ser137 in the sulfuryl transfer reaction.
Related PDB	1hy3
Related UniProtKB

Comments
According to the paper [1], the catalytic mechanism of this enzyme, EST, can involve SN2 attack by the 3alpha-pehoxide of the substrate on the sulfate of PAPS. Moreover, the trigonal bi-pyramidal transition state intermediate of the reaction could be stablized by positively charged Lys106 and Lys48. This paper also mentioned the fundamental differences between sulfonation and phosphorylation [1]. In sulfonation, the charge on the transferred sulfur trioxide [SO3] is 0, whilst the charge on the metaphosphate [PO3-] is -1 for phosphorylation at physiological pH. Moreover, catalysis involving phosphorylation frequently requires presence of a metal ion, usually magnesium. Yet, there is little evidence suggesting that metal ions are required for sulfotransferase activity [1]. The literature [2] reported the transition-state like structure with EST-PAP-vanadate complex, in which vanadium atom mimicks the transferring sulfate group. The structure suggested the transition state of an in-line transfer reaction. The stabilization by Lys48, His108, and Lys106 of the transition state may also be essential for the high catalytic efficiency [2]. According to the literature [4], the catalytic mechanism is proposed as follows: The conserved histidine (His108 for 1aqu) can be a general base that abstracts the proton from the acceptor hydroxy group, thereby converting this group to a strong nuceophile. Once formed, the nucleophile attacks the sulfur atom of PAPS, which in turn leads to an accumulation of negative charge at the bridging oxygen (i.e., leaving oxygen) between the 5'-phosphate and sulfate. On the other hand, the conserved lysine (Lys48 for 1aqu) residue may donate its proton to the bridging oxygen, thereby assisting in the dissociation of the sulfate group from PAPS. This catalytic lysine must also stabilize the transient state in aiding the dissociation of the sulfate from the PAPS. The conserved serine residue (Ser138 for 1aqu) seems to regulate the sulfur transfer reaction as the switch for the catalytic lysine, through its interaction. The sidechain coordination of the serine residue to the catalytic lysine occurs subsequent to the binding of the 3'-phosphate of PAPS to this serine. Whereas the serine interacts with the lysine to decrease the PAPS hydrolysis, the sidechain nitrogen of the lysine must be coordinated with the bridging oxygen to play a role as catalytic acid. The conserved histidine may play the major role in the switch as the catalytic base. Following the substrate binding, the histidine removes the proton from the acceptor group, making it the nucleophile that subsequently attacks the sulfur atom of the PAPS molecule. Negative charge accumulates on the bridging oxygen. Finally, the developing negative charge forces the sidechain nitrogen of the catalytic lysine to switch from the serine to the bridging oxygen and the sulfate dissociation occurs [4],[5].

Comments

According to the paper [1], the catalytic mechanism of this enzyme, EST, can involve SN2 attack by the 3alpha-pehoxide of the substrate on the sulfate of PAPS. Moreover, the trigonal bi-pyramidal transition state intermediate of the reaction could be stablized by positively charged Lys106 and Lys48.
This paper also mentioned the fundamental differences between sulfonation and phosphorylation [1]. In sulfonation, the charge on the transferred sulfur trioxide [SO3] is 0, whilst the charge on the metaphosphate [PO3-] is -1 for phosphorylation at physiological pH. Moreover, catalysis involving phosphorylation frequently requires presence of a metal ion, usually magnesium. Yet, there is little evidence suggesting that metal ions are required for sulfotransferase activity [1].
The literature [2] reported the transition-state like structure with EST-PAP-vanadate complex, in which vanadium atom mimicks the transferring sulfate group. The structure suggested the transition state of an in-line transfer reaction. The stabilization by Lys48, His108, and Lys106 of the transition state may also be essential for the high catalytic efficiency [2].
According to the literature [4], the catalytic mechanism is proposed as follows:
The conserved histidine (His108 for 1aqu) can be a general base that abstracts the proton from the acceptor hydroxy group, thereby converting this group to a strong nuceophile. Once formed, the nucleophile attacks the sulfur atom of PAPS, which in turn leads to an accumulation of negative charge at the bridging oxygen (i.e., leaving oxygen) between the 5'-phosphate and sulfate. On the other hand, the conserved lysine (Lys48 for 1aqu) residue may donate its proton to the bridging oxygen, thereby assisting in the dissociation of the sulfate group from PAPS. This catalytic lysine must also stabilize the transient state in aiding the dissociation of the sulfate from the PAPS.
The conserved serine residue (Ser138 for 1aqu) seems to regulate the sulfur transfer reaction as the switch for the catalytic lysine, through its interaction. The sidechain coordination of the serine residue to the catalytic lysine occurs subsequent to the binding of the 3'-phosphate of PAPS to this serine. Whereas the serine interacts with the lysine to decrease the PAPS hydrolysis, the sidechain nitrogen of the lysine must be coordinated with the bridging oxygen to play a role as catalytic acid. The conserved histidine may play the major role in the switch as the catalytic base. Following the substrate binding, the histidine removes the proton from the acceptor group, making it the nucleophile that subsequently attacks the sulfur atom of the PAPS molecule. Negative charge accumulates on the bridging oxygen. Finally, the developing negative charge forces the sidechain nitrogen of the catalytic lysine to switch from the serine to the bridging oxygen and the sulfate dissociation occurs [4],[5].

Created	Updated
2002-05-02	2009-02-26