In
enzymology, a steroid sulfotransferase () is an
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...
that
catalyzes the
chemical reaction
A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the pos ...
:3'-phosphoadenylyl sulfate + a phenolic steroid
adenosine 3',5'-bisphosphate + steroid O-sulfate
Thus, the two
substrates of this enzyme are
3'-phosphoadenylyl sulfate and
phenolic steroid, whereas its two
products
Product may refer to:
Business
* Product (business), an item that serves as a solution to a specific consumer problem.
* Product (project management), a deliverable or set of deliverables that contribute to a business solution
Mathematics
* Produ ...
are
adenosine 3',5'-bisphosphate and
steroid O-sulfate.
This enzyme belongs to the family of
transferase
A transferase is any one of a class of enzymes that catalyse the transfer of specific functional groups (e.g. a methyl or glycosyl group) from one molecule (called the donor) to another (called the acceptor). They are involved in hundreds of ...
s, specifically the sulfotransferases, which transfer sulfur-containing groups. The
systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature.
A semisystematic name or semitrivial ...
of this enzyme class is 3'-phosphoadenylyl-sulfate:phenolic-steroid sulfotransferase. This enzyme is also called steroid alcohol sulfotransferase. This enzyme participates in
steroid metabolism
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run c ...
.
Genes
Of 62 sulfotransferase genes in the human genome, 16 represent cytoplasmic sulfotransferases, and of these 16 cytoplasmic sulfotransferases, five have been found to act as steroid sulfotransferases.
These five sulfotransferase genes are
SULT1A1,
SULT1E1
Estrogen sulfotransferase is an enzyme that in humans is encoded by the ''SULT1E1'' gene.
Sulfotransferase enzymes catalyze the sulfate conjugation of many hormones, neurotransmitters, drugs, and xenobiotic compounds. These cytosolic enzymes are ...
, and
SULT2A1
Bile salt sulfotransferase also known as hydroxysteroid sulfotransferase (HST) or sulfotransferase 2A1 (ST2A1) is an enzyme that in humans is encoded by the ''SULT2A1'' gene.
Function
Sulfotransferase enzymes catalyze the sulfate conjugation ...
, as well as the two isoforms of
SULT2B1,
SULT2B1a
Sulfotransferase family cytosolic 2B member 1 is an enzyme that in humans is encoded by the ''SULT2B1'' gene.
Sulfotransferase enzymes catalyze the sulfate conjugation of many hormones, neurotransmitters, drugs, and xenobiotic chemical compound ...
and
SULT2B1b.
Their substrate specificity is as follows:
* SULT1A1:
Estradiol
Estradiol (E2), also spelled oestradiol, is an estrogen steroid hormone and the major female sex hormone. It is involved in the regulation of the estrous and menstrual female reproductive cycles. Estradiol is responsible for the development o ...
(to
estradiol sulfate
Estradiol sulfate (E2S), or 17β-estradiol 3-sulfate, is a natural, endogenous steroid and an estrogen ester. E2S itself is biologically inactive, but it can be converted by steroid sulfatase (also called estrogen sulfatase) into estradiol, whi ...
)
* SULT1E1: (to
sulfate);
Estrone
Estrone (E1), also spelled oestrone, is a steroid, a weak estrogen, and a minor female sex hormone. It is one of three major endogenous estrogens, the others being estradiol and estriol. Estrone, as well as the other estrogens, are synthesized ...
(to
estrone sulfate
Estrone sulfate, also known as E1S, E1SO4 and estrone 3-sulfate, is a natural, endogenous steroid and an estrogen ester and conjugate.
In addition to its role as a natural hormone, estrone sulfate is used as a medication, for instance in menop ...
); Estradiol (to estradiol sulfate)
* SULT2A1: (to sulfate);
Androsterone
Androsterone, or 3α-hydroxy-5α-androstan-17-one, is an endogenous steroid hormone, neurosteroid, and putative pheromone. It is a weak androgen with a potency that is approximately 1/7 that of testosterone. Androsterone is a metabolite of test ...
(to
androsterone sulfate
Androsterone sulfate, also known as 3α-hydroxy-5α-androstan-17-one 3α-sulfate, is an endogenous, naturally occurring steroid and one of the major urinary metabolites of androgens. It is a steroid sulfate which is formed from sulfation of an ...
);
Pregnenolone
Pregnenolone (P5), or pregn-5-en-3β-ol-20-one, is an endogenous steroid and precursor/ metabolic intermediate in the biosynthesis of most of the steroid hormones, including the progestogens, androgens, estrogens, glucocorticoids, and mineraloc ...
(to
pregnenolone sulfate
Pregnenolone sulfate (PS, PREGS) is an endogenous excitatory neurosteroid that is synthesized from pregnenolone. It is known to have cognitive and memory-enhancing, antidepressant, anxiogenic, and proconvulsant effects.
Biological activity
Pr ...
)
* SULT2B1a: Pregnenolone (to pregnenolone sulfate)
* SULT2B1b:
Cholesterol
Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell mem ...
(to
cholesterol sulfate)
Traditionally, steroid sulfotransferases have been named according to their preferred substrate, for instance estrogen sulfotransferase (SULT1E1) and DHEA sulfotransferase (SULT2A1).
However, cytosolic steroid sulfotransferases show broad substrate specificity, and SULT1E1 and SULT2A1 are not the only steroid sulfotransferases that sulfate estrogens and DHEA, respectively.
See also
*
Estrogen sulfotransferase
*
Estrone sulfotransferase
Estrone sulfotransferase (EST) (), also known as estrogen sulfotransferase, is an enzyme that catalyzes the transformation of an unconjugated estrogen like estrone into a sulfated estrogen like estrone sulfate. It is a steroid sulfotransferase ...
*
Steroid sulfatase
*
Steroidogenic enzyme __NOTOC__
Steroidogenic enzymes are enzymes that are involved in steroidogenesis and steroid biosynthesis. They are responsible for the biosynthesis of the steroid hormones, including sex steroids (androgens, estrogens, and progestogens) and cortic ...
References
*
EC 2.8.2
Enzymes of unknown structure
{{2.8-enzyme-stub