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Catalytic Site Atlas

CSA LITERATURE entry for 2dhn

E.C. namedihydroneopterin aldolase
SpeciesStaphylococcus aureus (Bacteria)
E.C. Number (IntEnz)
CSA Homologues of 2dhnThere are 19 Homologs
CSA Entries With UniProtID P56740
CSA Entries With EC Number
PDBe Entry 2dhn
PDBSum Entry 2dhn
MACiE Entry 2dhn

Literature Report

Introduction7,8 dihydroneopterin from Staphylococcus aureus is able to catalyse the conversion of 7,8 dihydroneopterin to 6 hydroxymethyl 7,8 dihydroneopterin, an aldol cleavage reaction which also produces glycoaldehyde, a key step in the synthesis of folate, which can in turn be used for the synthesis of purines. The enzyme is an attractive target for antibiotics, as the it is found in MRSA, thus structural information can be used to design inhibitors of the enzyme.
MechansimThe reaction is an aldol cleavage reaction similar to those catalysed by aldolases. Deprotonation of the 7C OH by Lys 100, assisted by Glu 22, results in an unstable enamine intermediate which collapses to form the products glycoaldehyde and deprotonated 6 hydroxymethyl dho which picks up a proton from Lys 100 to regenerate the catalytically active form of the enzyme.

Catalytic Sites for 2dhn

Annotated By Reference To The Literature - Site 1 (Perform Site Search)
ResidueChainNumberUniProtKB NumberFunctional PartFunctionTargetDescription
GluA2222macie:sideChainAssists in the deprotonation of the substrate by maintaining Lys 100 in the correct protonation state through electrostatic contacts with the residue.
LysA100100macie:sideChainDeprotonates the substrate thus forming the unstable enamine intermediate which collapses to release the products. Subsequently reprotonates the product to regenerate the active form of the enzyme.

Literature References

Hennig M
Crystal structure and reaction mechanism of 7,8-dihydroneopterin aldolase from Staphylococcus aureus.
Nat Struct Biol 1998 5 357-362
PubMed: 9586996