The dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase from Haemophilus influenzae is a dinuclear metallohydrolase.
The Zn K-edge extended X-ray absorption fine structure (EXAFS) spectra, of the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE) from Haemophilus influenzae have been recorded in the presence of one or two equivalents of Zn(II) (i.e. [Zn_(DapE)] and [ZnZn(DapE)]). The Fourier transforms of the Zn EXAFS are dominated by a peak at ca. 2.0 A, which can be fit for both [Zn_(DapE)] and [ZnZn(DapE)], assuming ca. 5 (N,O) scatterers at 1.96 and 1.98 A, respectively. A second-shell feature at ca. 3.34 A appears in the [ZnZn(DapE)] EXAFS spectrum but is significantly diminished in [Zn_(DapE)]. These data show that DapE contains a dinuclear Zn(II) active site. Since no X-ray crystallographic data are available for any DapE enzyme, these data provide the first glimpse at the active site of DapE enzymes. In addition, the EXAFS data for DapE incubated with two competitive inhibitors, 2-carboxyethylphosphonic acid and 5-mercaptopentanoic acid, are also presented.
Cosper
Nathaniel J
NJ
Department of Chemistry and Biochemistry, Utah State University, Logan, UT 84322-0300, USA.
Bienvenue
David L
DL
Shokes
Jacob E
JE
Gilner
Danuta M
DM
Tsukamoto
Takashi
T
Scott
Robert A
RA
Holz
Richard C
RC
D000581:Amidohydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000378:metabolism / Q000494:pharmacology; D005583:Fourier Analysis; D006193:Haemophilus influenzae / Q000201:enzymology* / Q000235:genetics; D013052:Spectrometry, X-Ray Emission / Q000379:methods
D000581:Amidohydrolases; D004791:Enzyme Inhibitors; C054685:N-succinyl-l,l-diaminopimelic acid desuccinylase