Structural characterization of an acetolactate decarboxylase from Klebsiella pneumoniae.
Biochem Biophys Res Commun
; 509(1): 154-160, 2019 01 29.
Article
in En
| MEDLINE
| ID: mdl-30580999
Acetolactate decarboxylase (ALDC) is a well-characterized anabolic enzyme involved with 3-hydroxy butanone (acetoin), an important physiological metabolite excreted by microbes. Although the enzyme is widely present in microorganisms, few atomic structures and functions of ALDC have been reported to date. Here we report the crystal structure of ALDC from Klebsiella pneumoniae KP (KpALDC). KpALDC crystallizes in space group P3121 with one monomer per asymmetric unit. Analytical ultracentrifugation data shows that KpALDC forms a stable dimer but can exist as a tetramer in solution. A Zn2+ ion is coordinated by three strictly-conserved histidines (His198, His200 and His211) and a conserved glutamate (Glu69), but the C-terminal tail that forms part of the active site in ALDC enzymes is disordered. A complex structure with ethane-1,2-diol shows a unusual mode of binding, whereby the ligand does not coordinate the Zn2+ ion. MicroScale Thermophoresis analysis shows that KpALDC binds Zn2+ ions, but no binding of Mg2+, Ca2+ and Mn2+ ions was detected.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Carboxy-Lyases
/
Klebsiella pneumoniae
Limits:
Humans
Language:
En
Journal:
Biochem Biophys Res Commun
Year:
2019
Document type:
Article
Affiliation country:
China
Country of publication:
United States