title: Chemoenzymatic syntheses of water-soluble lipid I fluorescent probes.
abstract: Peptidoglycan (PG) is unique to bacteria, and thus, the enzymes responsible for its biosynthesis are promising antibacterial drug targets. The membrane-embedded enzymes in PG remain significant challenges in studying their mechanisms due to the fact that preparations of suitable enzymatic substrates require time-consuming biological transformations or chemical synthesis. Lipid I (prenyl diphosphoryl-MurNAc-pentapeptide) is an important PG biosynthesis intermediate to study the central enzymes, translocase I (MraY/MurX) and MurG. Lipid I isolated from nature contains the C50-or C55-prenyl unit that shows extremely poor water-solubility that renders studies of translocase I and MurG enzymes difficult. We have studied biological transformation of water soluble lipid I fluorescent probes using bacterial membrane fractions and purified MraY enzymes. In our investigation of the minimum structural requirements of the prenyl phosphates in MraY-catalyzed lipid I synthesis, we found that (2Z,6E)-farnesyl phosphate (C15-phosphate) can be recognized byE. coliMraY to generate the water-soluble lipid I fluorescent probes in high-yield. Under the optimized conditions, the same reaction was performed by using the purified MraY fromHydrogenivirga spp.to afford the lipid I analog with high-yield in a short reaction time.
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, TN 38163, USA.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Mitachi
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, TN 38163, USA.
authors.forename: Shajila
authors.initials: S
authors.lastname: Siricilla
authors.affiliation: Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Bld. Pasadena, CA 91125, USA.
authors.forename: Lada
authors.initials: L
authors.lastname: Klaic
authors.affiliation: Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Bld. Pasadena, CA 91125, USA.
authors.forename: William M
authors.initials: WM
authors.lastname: Clemons
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, TN 38163, USA.
authors.forename: Michio
authors.initials: M
authors.lastname: Kurosu
keywords: Chemoenzymatic synthesis; Lipid I; Lipid II; MurG; Translocase I (MraY/MurX)