AI Article Synopsis
- A FemA mutant of Staphylococcus aureus was grown with an alanine-racemase inhibitor and labeled with various isotopes to study its peptidoglycan structure.
- The study utilized rotational-echo double-resonance (REDOR) NMR techniques to measure distances between carbon-labeled alanines and fluorine-labeled lysine within the isolated cell walls.
- The findings revealed a compact structure of the peptidoglycan, featuring a repeating motif organized in both parallel and perpendicular orientations.
Article Abstract
Staphylococcus aureus FemA mutant grown in the presence of an alanine-racemase inhibitor was labeled with d-[1-(13)C]alanine, l-[3-(13)C]alanine, [2-(13)C]glycine, and l-[5-(19)F]lysine to characterize some details of the peptidoglycan tertiary structure. Rotational-echo double-resonance (REDOR) NMR of isolated cell walls was used to measure internuclear distances between (13)C-labeled alanines and (19)F-labeled lysine incorporated in the peptidoglycan. The alanyl (13)C labels were preselected for REDOR measurement by their proximity to the glycine label using (13)C-(13)C spin diffusion. The observed (13)C-(13)C and (13)C-(19)F distances are consistent with a tightly packed, hybrid architecture containing both parallel and perpendicular stems in a repeating structural motif within the peptidoglycan.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3985804 | PMC |
| http://dx.doi.org/10.1021/bi4016742 | DOI Listing |
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