Sidewall cell envelope synthesis and remodeling in pole-growing mycobacteria

Garcia-Heredia, A.; Pohane, A. A.; Melzer, E. S.; Fiolek, T. J.; Rundell, S. R.; Lim, H. C.; Wagner, J.; Morita, Y. S.; Swarts, B. M.; Siegrist, M. S.

doi:10.1101/292607

bioRxiv · 10.1101/292607

Sidewall cell envelope synthesis and remodeling in pole-growing mycobacteria

Garcia-Heredia, A.·Pohane, A. A.·Melzer, E. S.·Fiolek, T. J.·Rundell, S. R.·Lim, H. C.·Wagner, J.·Morita, Y. S.·Swarts, B. M.·Siegrist, M. S.

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Abstract

O_SCPLOWDC_SCPLOW-amino acid probes label cell wall peptidoglycan at both the poles and sidewall of pole-growing mycobacteria. Since peptidoglycan assembly along the cell periphery could provide a rapid, growth-independent means by which to edit the cell wall, we sought to clarify the precise metabolic fates of these probes. O_SCPLOWDC_SCPLOW-amino acid monopeptides were incorporated into peptidoglycan by O_SCPLOWLC_SCPLOWO_SCPCAP,C_SCPCAPO_SCPLOWDC_SCPLOW-transpeptidase remodeling enzymes to varying extents. Dipeptides were incorporated into cytoplasmic precursors. While dipeptide-marked peptidoglycan synthesis at the poles was associated with cell elongation, synthesis along the periphery was highly responsive to cell wall damage. Our observations suggest a post-expansion role for peptidoglycan assembly along the mycobacterial sidewall and provide a conceptual framework for understanding cell wall robustness in the face of polar growth.

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Garcia-Heredia, A., Pohane, A. A., Melzer, E. S., Fiolek, T. J., Rundell, S. R., Lim, H. C., Wagner, J., Morita, Y. S., Swarts, B. M., Siegrist, M. S.. 2018-03-31. Sidewall cell envelope synthesis and remodeling in pole-growing mycobacteria. https://doi.org/10.1101/292607

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