Determination of kinetics and the crystal structure of a novel type 2 isopentenyl diphosphate: dimethylallyl diphosphate isomerase from Streptococcus pneumoniae.
Chembiochem
; 15(10): 1452-8, 2014 Jul 07.
Article
em En
| MEDLINE
| ID: mdl-24910111
ABSTRACT
Isopentenyl diphosphate isomerase (IDI) is a key enzyme in the isoprenoid biosynthetic pathway and is required for all organisms that synthesize isoprenoid metabolites from mevalonate. Type 1 IDI (IDI-1) is a metalloprotein that is found in eukaryotes, whereas the type 2 isoform (IDI-2) is a flavoenzyme found in bacteria that is completely absent from human. IDI-2 from the pathogenic bacterium Streptococcus pneumoniae was recombinantly expressed in Escherichia coli. Steady-state kinetic studies of the enzyme indicated that FMNH2 (KM =0.3 µM) bound before isopentenyl diphosphate (KM =40 µM) in an ordered binding mechanism. An X-ray crystal structure at 1.4 Å resolution was obtained for the holoenzyme in the closed conformation with a reduced flavin cofactor and two sulfate ions in the active site. These results helped to further approach the enzymatic mechanism of IDI-2 and, thus, open new possibilities for the rational design of antibacterial compounds against sequence-similar and structure-related pathogens such as Enterococcus faecalis or Staphylococcus aureus.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Streptococcus pneumoniae
/
Isomerases de Ligação Dupla Carbono-Carbono
Limite:
Humans
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article