Aquifex aeolicus 3-deoxy-D-manno-2-octulosonic acid 8-phosphate synthase: a new class of KDO 8-P synthase?
The relationship between 3-deoxy-D-manno-2-octulosonic acid 8-phosphate (KDO 8-P) synthase and 3-deoxy-D-arabino-2-heptulosonic acid 7-phosphate (DAH 7-P) synthase has not been adequately addressed in the literature. Based on recent reports of a metal requiring KDO 8-P synthase and the newly solved X-ray crystal structures of both Escherichia coli KDO 8-P synthase and DAH 7-P synthase, we begin to address the evolutionary kinship between these catalytically similar enzymes. Using a maximum likelihood-based grouping of 29 KDO 8-P synthase sequences, we demonstrate the existence of a new class of KDO 8-P synthase, the members of which we propose to require a metal cofactor for catalysis. Similarly, we hypothesize a class of DAH 7-P synthase that does not have the metal requirement of the heretofore model E. coli enzyme. Based on this information and a careful investigation of the reported X-ray crystal structures, we also propose that KDO 8-P synthase and DAH 7-P synthase are the product of a divergent evolutionary process from a common ancestor.
Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 428 Church Street, Ann Arbor, MI 48109-1065, USA.
M R
MR
Birck
R W
RW
Woodard
D010723:3-Deoxy-7-Phosphoheptulonate Synthase / Q000737:chemistry / Q000235:genetics*; D000446:Aldehyde-Lyases / Q000737:chemistry / Q000235:genetics*; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001419:Bacteria / Q000201:enzymology / Q000235:genetics*; D001665:Binding Sites; D016208:Databases, Factual; D016013:Likelihood Functions; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010802:Phylogeny; D016415:Sequence Alignment
D010723:3-Deoxy-7-Phosphoheptulonate Synthase; C020011:2-dehydro-3-deoxyphosphooctonate aldolase; D000446:Aldehyde-Lyases