Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.1.1.1 (
alcohol dehydrogenase
)
9,284
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Alcohol dehydrogenase from horse (isoenzyme SS and ES, but not EE), rat and human liver were found to catalyze the NAD-dependent oxidation of 3beta-hydroxy groups in 5alpha- and 5beta-steroids of the C19,
C21
, and C24 series. The enzymes from horse and rat liver were more active on 5beta-than on 5alpha-steroids. This difference was most marked with the enzyme from rat liver, especially with 3beta-hydroxyandrostan-17-ones and 3beta-hydroxypregnan-20-ones as substrates. The Km of isoenzyme ES from horse liver was lower for 3beta-hydroxy-5alpha-cholanoic acid (0.4 muM) than for 3beta-hydroxy-5beta-cholanoic acid (0.9 muM). 3alpha-Hydroxysteroids were not substrates for the enzymes from horse and rat liver. Human liver
alcohol dehydrogenase
had low affinity for 3beta-hydroxy-5alpha (and 5beta)-cholanoic acids, but oxidation could be clearly demonstrated by gas chromatographic analysis of the products.
...
PMID:Steroid oxidoreductase activity of alcohol dehydrogenases from horse, rat, and human liver. 17 Jul 65
One step competitive enzyme linked immunosorbent assay (ELISA) for direct estimation of testosterone in human serum is described. Testosterone-3-O-carboxymethyl-oxime-bovine serum albumin (testosterone-3-O-CMO-BSA), was used as immunogen and testosterone-3-O-carboxymethyl-oxime-adipic-acid dihydrazide-horseradish peroxidase (testosterone-3-O-CMO-ADH-HRP) was used as tracer. To the testosterone antibody coated microtiter wells, standard or serum samples (100 microL), along with testosterone-3-O-CMO-
ADH
-HRP conjugate (100 microL) were incubated for 1 h at 37 degrees C. Bound enzyme activity was measured by using tetra methyl benzidine/hydrogen peroxide (TMB/H2O2) as a substrate. In this new strategy, charcoal stripped pooled human serum spiked with non-cross reactive C18, C19,
C21
, and C27 steroids, used for preparing the standards and blocking the sex hormone binding globulin (SHBG)/and other steroid binding globulins (SBG). The sensitivity of the assay was 0.015 ng/mL. The intra-assay and inter-assay coefficients of variation (CVs) were ranged from 7.8 to 11.8 and 4.8 to 10.4, respectively. The serum testosterone values, obtained by this method, were correlated well with those obtained by radioimmunoassay r = .98 (n = 100).
...
PMID:One step enzyme linked immunosorbent assay for direct estimation of serum testosterone. 1277 72
The polycyclic tetramate macrolactam HSAF is an antifungal natural product isolated from
Lysobacter enzymogenes
. HSAF and its analogues have a distinct chemical structure and new mode of antifungal action. The mechanism by which the 5/5/6 tricycle of HSAF is formed from the polyene precursor is not totally clear. Here, we used purified OX4, a homologous enzyme of
alcohol dehydrogenase
/Zn-binding proteins, to show the enzymatic mechanism for six-membered ring formation. The results from the deuterium isotope incorporation demonstrated that OX4 selectively transfers the
pro
-
R
hydride of NADPH to
C21
and one proton from water to C10 of 3-deOH alteramide C (
1
), resulting in 3-deOH HSAF (
2
) through a reductive cyclization of the polyene precursor by a mechanism consistent with an extended 1,6-Michael addition reaction. The regioselective incorporation of the NADPH hydride into
C21
of
1
is also stereoselective, leading to the 21
S
configuration of
2
. This work represents the first characterization of the activity and selectivity of the enzyme for six-membered ring formation in a group of distinct antifungal polycyclic tetramate macrolactams.
...
PMID:OX4 Is an NADPH-Dependent Dehydrogenase Catalyzing an Extended Michael Addition Reaction To Form the Six-Membered Ring in the Antifungal HSAF. 3103 29