Physical Sciences and Mathematics Commons^™

Substrate Specificity, Metal Binding Properties, And Spectroscopic Characterization Of The Dape-Encoded N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase From Haemophilus Influenzae, David L. Bienvenue, Danuta M. Gilner, Ryan S. Davis, Brian Bennett, Richard C. Holz

Physics Faculty Research and Publications

The catalytic and structural properties of divalent metal ion cofactor binding sites in the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE) from Haemophilus influenzae were investigated. Co(II)-substituted DapE enzyme was 25% more active than the Zn(II)-loaded form of the enzyme. Interestingly, Mn(II) can activate DapE, but only to ∼20% of the Zn(II)-loaded enzyme. The order of the observed k_cat values are Co(II) > Zn(II) > Cd(II) > Mn(II) >Ni(II) ∼ Cu(II) ∼ Mg(II). DapE was shown to only hydrolyze l,l-N-succinyl-diaminopimelic acid (l,l-SDAP) and was inactive toward d,l-, l,d-, and d,d-SDAP. DapE was also inactive toward several acetylated amino acids as …