title: A simple assay for 3-deoxy-d-manno-octulosonate cytidylyltransferase and its use as a pathway screen.
abstract: This article describes the adaptation of a simple colorimetric assay for inorganic pyrophosphate to the enzyme 3-deoxy-d-manno-octulosonate cytidylyltransferase (CMP-KDO synthetase, KdsB, EC 2.7.7.38), a key enzyme in the biosynthesis of lipopolysaccharide (LPS) in Gram-negative organisms. This assay is particularly useful because it can be combined with the malachite green (MG) assay for inorganic phosphate to form an assay system capable of determining inorganic phosphate and inorganic pyrophosphate in the same solution (the MG/EK (eikonogen reagent) assay). This assay system has the potential for simultaneous screening of the 3-deoxy-d-manno-octulosonate (KDO) biosynthesis pathway. We tested this potential using two enzymes, KdsB and KdsC, involved in the biosynthesis and use of the key bacterial 8-carbon sugar, KDO.
authors.affiliation: Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Yi
authors.forename: Melvin S
authors.initials: MS
authors.lastname: Velasquez
authors.forename: Tod P
authors.initials: TP
authors.lastname: Holler
authors.forename: Ronald W
authors.initials: RW
authors.lastname: Woodard
mesh_terms: D003124:Colorimetry / Q000379:methods*; D011756:Diphosphates / Q000032:analysis; D004926:Escherichia coli / Q000201:enzymology / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000378:metabolism; D007700:Kinetics; D009713:Nucleotidyltransferases / Q000378:metabolism*; D010710:Phosphates / Q000032:analysis; D012394:Rosaniline Dyes / Q000032:analysis; D013400:Sugar Acids / Q000737:chemistry / Q000378:metabolism
chemical_list: D011756:Diphosphates; D029968:Escherichia coli Proteins; D010710:Phosphates; D012394:Rosaniline Dyes; D013400:Sugar Acids; C002532:2-keto-3-deoxyoctonate; C005095:malachite green; D009713:Nucleotidyltransferases; C028984:3-deoxy-manno-octulosonate cytidyltransferase