Premium
Glyoxalase II from A. thaliana requires Zn(II) for catalytic activity
Author(s) -
Crowder Michael W.,
Maiti Mrinal K.,
Banovic Linda,
Makaroff Christopher A.
Publication year - 1997
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(97)01416-6
Subject(s) - chemistry , catalysis , arabidopsis thaliana , biochemistry , mutant , gene
Cytosolic glyoxalase II from Arabidopsis thaliana , GLX2‐2, was overexpressed and purified to homogeneity using Q‐sepharose chromatography. MALDI‐TOF mass spectrometry studies indicated a molecular weight of 28 767 Da. Using steady‐state kinetics studies, the purified enzyme exhibited a K m of 660±100 μM and a k cat of 484±92 s −1 at 37°C. Metal analyses demonstrated that the enzyme binds 2.1±0.5 moles of Zn(II) per monomer; the binding of Zn(II) is essential for enzyme viability and activity. Sequence comparison of glyoxalase II enzymes from human, A. thaliana , and yeast and the metallo‐β‐lactamases reveal that all metal binding ligands of the metallo‐β‐lactamases are conserved in glyoxalase II enzymes, suggesting that all glyoxalase II enzymes are Zn(II) metalloenzymes. These results and their implications are discussed in light of previous studies on glyoxalase II, and an active site for the glyoxalase II enzymes is proposed.