TY - JOUR
T1 - 1-Deoxy-D-xylulose 5-phosphate synthase catalyzes a novel random sequential mechanism
AU - Brammer, Leighanne A.
AU - Smith, Jessica M.
AU - Wades, Herschel
AU - Meyers, Caren Freel
PY - 2011/10/21
Y1 - 2011/10/21
N2 - Emerging resistance of human pathogens to anti-infective agents make it necessary to develop new agents to treat infection. The methylerythritol phosphate pathway has been identified as an anti-infective target, as this essential isoprenoid biosynthetic pathway is widespread in human pathogens but absent in humans. The first enzyme of the pathway, 1-deoxy-D-xylulose 5-phosphate (DXP) synthase, catalyzes the formation of DXP via condensation of D-glyceraldehyde 3-phosphate (D-GAP) and pyruvate in a thiamine diphosphate-dependent manner. Structural analysis has revealed a unique domain arrangement suggesting opportunities for the selective targeting of DXP synthase; however, reports on the kinetic mechanism are conflicting. Here, we present the results of tryptophan fluorescence binding and kinetic analyses of DXP synthase and propose a new model for substrate binding and mechanism. Our results are consistent with a random sequential kinetic mechanism, which is unprecedented in this enzyme class.
AB - Emerging resistance of human pathogens to anti-infective agents make it necessary to develop new agents to treat infection. The methylerythritol phosphate pathway has been identified as an anti-infective target, as this essential isoprenoid biosynthetic pathway is widespread in human pathogens but absent in humans. The first enzyme of the pathway, 1-deoxy-D-xylulose 5-phosphate (DXP) synthase, catalyzes the formation of DXP via condensation of D-glyceraldehyde 3-phosphate (D-GAP) and pyruvate in a thiamine diphosphate-dependent manner. Structural analysis has revealed a unique domain arrangement suggesting opportunities for the selective targeting of DXP synthase; however, reports on the kinetic mechanism are conflicting. Here, we present the results of tryptophan fluorescence binding and kinetic analyses of DXP synthase and propose a new model for substrate binding and mechanism. Our results are consistent with a random sequential kinetic mechanism, which is unprecedented in this enzyme class.
UR - http://www.scopus.com/inward/record.url?scp=80054712655&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80054712655&partnerID=8YFLogxK
U2 - 10.1074/jbc.M111.259747
DO - 10.1074/jbc.M111.259747
M3 - Article
C2 - 21878632
AN - SCOPUS:80054712655
SN - 0021-9258
VL - 286
SP - 36522
EP - 36531
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 42
ER -