Structures of Staphylococcus aureus Cell-Wall Complexes with Vancomycin, Eremomycin, and Chloroeremomycin Derivatives by 13C{19F} and 15N{19F} Rotati
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- 作者：Sung Joon Kim ; Lynette Cegelski ; Maria Preobrazhenskaya ; and Jacob Schaefer
- 刊名：Biochemistry
- 出版年：2006
- 出版时间：April 25, 2006
- 年：2006
- 卷：45
- 期：16
- 页码：5235 - 5250
- 全文大小：1154K
- 年卷期：v.45,no.16(April 25, 2006)
- ISSN：1520-4995
文摘
Solid-state NMR has been used to examine isolated cell walls and intact whole cells ofStaphylococcus aureus complexed to five different vancomycin, eremomycin, and chloroeremomycinderivatives. The cell walls and whole cells were specifically labeled with D-[1-13C]alanine, or a combinationof [1-13C]glycine and [
-15N]lysine. Each of the bound glycopeptides had a 19F-labeled substituent ateither its C-terminus or its disaccharide position. The 13C{19F} rotational-echo double-resonance (REDOR)dephasing for the cell-wall 13C-labeled bridging pentaglycyl segment connecting a glycopeptide-complexedpeptidoglycan stem with its neighboring stem indicates that the fluorine labels for all bound glycopeptidesare positioned at one or the other end of the bridge. An exception is N'-(p-trifluoromethoxybenzyl)chloroeremomycin, whose hydrophobic substituent differs in length by one phenyl group compared tothat of oritavancin, N'-4-[(4-chlorophenyl)benzyl)]chloroeremomycin. For this drug, the fluorine label isnear the middle of the pentaglycyl segment. 15N{19F} REDOR dephasing shows the proximity of thefluorine to the bridge-link site of the pentaglycyl bridge for C-terminus-substituted moieties and the cross-link site for disaccharide-substituted moieties. Full-echo REDOR spectra of cell-wall complexes fromcells labeled by D-[1-13C]alanine (in the presence of an alanine racemase inhibitor) reveal three differentcarbonyl carbon chemical-shift environments, arising from the D-Ala-D-Ala binding site and the D-Ala-Gly-1 cross-link site. The REDOR results indicate a single fluorine dephasing center in each peptidoglycancomplex. Molecular models of the mature cell-wall complexes that are consistent with internuclear distancesobtained from 13C{19F} and 15N{19F} REDOR dephasing allow a correlation of structure and antimicrobialactivity of the glycopeptides.
-15N]lysine. Each of the bound glycopeptides had a 19F-labeled substituent ateither its C-terminus or its disaccharide position. The 13C{19F} rotational-echo double-resonance (REDOR)dephasing for the cell-wall 13C-labeled bridging pentaglycyl segment connecting a glycopeptide-complexedpeptidoglycan stem with its neighboring stem indicates that the fluorine labels for all bound glycopeptidesare positioned at one or the other end of the bridge. An exception is N'-(p-trifluoromethoxybenzyl)chloroeremomycin, whose hydrophobic substituent differs in length by one phenyl group compared tothat of oritavancin, N'-4-[(4-chlorophenyl)benzyl)]chloroeremomycin. For this drug, the fluorine label isnear the middle of the pentaglycyl segment. 15N{19F} REDOR dephasing shows the proximity of thefluorine to the bridge-link site of the pentaglycyl bridge for C-terminus-substituted moieties and the cross-link site for disaccharide-substituted moieties. Full-echo REDOR spectra of cell-wall complexes fromcells labeled by D-[1-13C]alanine (in the presence of an alanine racemase inhibitor) reveal three differentcarbonyl carbon chemical-shift environments, arising from the D-Ala-D-Ala binding site and the D-Ala-Gly-1 cross-link site. The REDOR results indicate a single fluorine dephasing center in each peptidoglycancomplex. Molecular models of the mature cell-wall complexes that are consistent with internuclear distancesobtained from 13C{19F} and 15N{19F} REDOR dephasing allow a correlation of structure and antimicrobialactivity of the glycopeptides.