Escherichia coli K-12 substr. MG1655 Reaction:

Superclasses: Reactions Classified By Conversion Type Simple Reactions Chemical Reactions
Reactions Classified By Substrate Small-Molecule Reactions

EC Number:

Enzymes and Genes:
UDP-sugar hydrolase Inferred from experiment : ushA

Reaction Locations: periplasmic space (sensu Gram-negative Bacteria)

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction in which it was curated.

Most BioCyc compounds have been protonated to a reference pH value of 7.3, and some reactions have been computationally balanced for hydrogen by adding free protons. Please see the PGDB Concepts Guide for more information.

Mass balance status: Marked as unbalanced.

Enzyme Commission Primary Name: UDP-sugar diphosphatase

Enzyme Commission Synonyms: nucleosidediphosphate-sugar pyrophosphatase, nucleosidediphosphate-sugar diphosphatase, UDP-sugar hydrolase, UDP-sugar pyrophosphatase

Enzyme Commission Summary:
A divalent cation is required for activity. UDP-sugar is the best substrate, although other nucleoside-sugar diphosphates are used as substrates with similar Km values but much lower maximum velocities. Thus, this enzyme has a specificity distinct from that of ADP-sugar diphosphatase (EC Some but not all enzymes of this class also appear to have 5′-nucleotidase (see EC activity.

Citations: [Glaser67, Garrett89]

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

Instance reaction of [a nucleoside 5'-monophosphate[periplasmic space] + H2O[periplasmic space] → a nucleoside[periplasmic space] + phosphate[periplasmic space]] (no EC#):
i1: a ribonucleoside 5'-monophosphate + H2O → a ribonucleoside + phosphate (

Instance reactions of [a ribonucleoside 5'-monophosphate + H2O → a ribonucleoside + phosphate] (
i2: CMP + H2O → cytidine + phosphate (

i3: UMP + H2O → uridine + phosphate (

i4: AMP + H2O → adenosine + phosphate (

Instance reactions of [a 2'-deoxyribonucleoside 5'-monophosphate + H2O → a 2'-deoxynucleoside + phosphate] (
i5: dCMP + H2O → 2'-deoxycytidine + phosphate (

i6: dUMP + H2O → 2'-deoxyuridine + phosphate (

i7: dTMP + H2O → thymidine + phosphate (

i8: dAMP + H2O → 2'-deoxyadenosine + phosphate (

i9: dGMP + H2O → 2'-deoxyguanosine + phosphate (

Relationship Links: BRENDA:EC: , ENZYME:EC: , IUBMB-ExplorEnz:EC:


Garrett89: Garrett AR, Johnson LA, Beacham IR (1989). "Isolation, molecular characterization and expression of the ushB gene of Salmonella typhimurium which encodes a membrane-bound UDP-sugar hydrolase." Mol Microbiol 3(2);177-86. PMID: 2548058

Glaser67: Glaser L, Melo A, Paul R (1967). "Uridine diphosphate sugar hydrolase. Purification of enzyme and protein inhibitor." J Biol Chem 1967;242(8);1944-54. PMID: 5337593

Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of EcoCyc: Nucleic Acids Research 41:D605-12 2013
Page generated by SRI International Pathway Tools version 19.0 on Tue Oct 6, 2015, BIOCYC14B.