1.13.11.91: 3-mercaptopropionate dioxygenase
This is an abbreviated version!
For detailed information about 3-mercaptopropionate dioxygenase, go to the full flat file.
Word Map on EC 1.13.11.91
-
1.13.11.91
-
non-heme
-
sulfinic
-
l-cysteine
-
vinelandii
-
paramagnetic
-
cysteamine
-
3-sulfinopropionic
-
dioxygenation
-
ferrous
-
denticity
-
bidentate
-
paradoxus
-
polythioester
-
thioether
-
advenella
-
thiol-containing
-
iron-nitrosyl
-
so2
-
biotechnical
-
variovorax
-
dtdp
-
mercaptosuccinate
-
mimigardefordensis
- 1.13.11.91
-
non-heme
-
sulfinic
- l-cysteine
- vinelandii
-
paramagnetic
- cysteamine
-
3-sulfinopropionic
-
dioxygenation
-
ferrous
-
denticity
-
bidentate
- paradoxus
-
polythioester
- thioether
-
advenella
-
thiol-containing
-
iron-nitrosyl
- so2
-
biotechnical
-
variovorax
- dtdp
- mercaptosuccinate
- mimigardefordensis
Reaction
Synonyms
3-mercaptopropionic acid dioxygenase, 3-sulfanylpropanoate dioxygenase, 3MDO, 3MP dioxygenase, CdoA, H16_B1863, MDO, NP_251292, PA2602
ECTree
Advanced search results
General Information
General Information on EC 1.13.11.91 - 3-mercaptopropionate dioxygenase
Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
metabolism
physiological function
active-site cluster models and comparison of CDO, EC 1.13.11.20, and 3-mercaptopropionate dioxygenase MDO. The enzymes have different iron(III)-superoxo-bound structures due to differences in ligand coordination. The differences in the second-coordination sphere and particularly the position of a positively charged Arg residue result in changes in substrate positioning, mobility and enzymatic turnover. For both enzymes, the second oxygen atom transfer has the highest barriers with magnitudes of 14.2 and 15.8 kcal/mol, respectively. Both enzymes have an open-shell singlet-spin iron(III)-superoxo reactant with the substrate bound as a bidentate ligand in the equatorial plane, in MDO the quintet spin state is within 1 kcal/mol. MDO binds the substrate through two anionic bonds of the substrate carboxylate and thiolate groups, and a strong hydrogen-bonding interaction of a Tyr residue towards the superoxo group in MDO is found
metabolism
-
active-site cluster models and comparison of CDO, EC 1.13.11.20, and 3-mercaptopropionate dioxygenase MDO. The enzymes have different iron(III)-superoxo-bound structures due to differences in ligand coordination. The differences in the second-coordination sphere and particularly the position of a positively charged Arg residue result in changes in substrate positioning, mobility and enzymatic turnover. For both enzymes, the second oxygen atom transfer has the highest barriers with magnitudes of 14.2 and 15.8 kcal/mol, respectively. Both enzymes have an open-shell singlet-spin iron(III)-superoxo reactant with the substrate bound as a bidentate ligand in the equatorial plane, in MDO the quintet spin state is within 1 kcal/mol. MDO binds the substrate through two anionic bonds of the substrate carboxylate and thiolate groups, and a strong hydrogen-bonding interaction of a Tyr residue towards the superoxo group in MDO is found
-
-
a network of hydrogen bonds connects residues H157-Y159 and Fe-bound ligands within the enzymatic Fe site. The hydroxyl group of Y159 hydrogen bonds to Fe-bound NO and, by extension, Fe-bound oxygen during native catalysis. This interaction alters both the NO binding affinity and rhombicity of the 3-mercaptopropanoate-bound iron-nitrosyl site
physiological function
mutants are impaired in growth on 3,3-thiodipropionic acid
physiological function
the monoprotonated ES complexes with 3-mercaptopropionic acid and cysteine have different pKs. At higher pH, kcat decreases sigmoidally with a similar pK regardless of substrate. Loss of reactivity at high pH is attributed to deprotonation of tyrosine 159 and its influence on dioxygen binding. A mechanism model shows deprotonation of tyrosine 159 both blocks oxygen binding and concomitantly promotes cystine formation
physiological function
-
the pL-dependent activity of MDO can be rationalized assuming a diprotic enzyme model in which three ionic forms of the enzyme are present [cationic, E(z+1), neutral, Ez, and anionic, E(z-1)]. The activities observed for substrates 3-mercaptopropanoate and cysteine appear to be dominated by electrostatic interactions within the enzymatic active site
physiological function
-
the monoprotonated ES complexes with 3-mercaptopropionic acid and cysteine have different pKs. At higher pH, kcat decreases sigmoidally with a similar pK regardless of substrate. Loss of reactivity at high pH is attributed to deprotonation of tyrosine 159 and its influence on dioxygen binding. A mechanism model shows deprotonation of tyrosine 159 both blocks oxygen binding and concomitantly promotes cystine formation
-