TY - JOUR TI - Maturing Mycobacterium smegmatis peptidoglycan requires non-canonical crosslinks to maintain shape AU - Baranowski, Catherine AU - Welsh, Michael A AU - Sham, Lok-To AU - Eskandarian, Haig A AU - Lim, Hoong Chuin AU - Kieser, Karen J AU - Wagner, Jeffrey C AU - McKinney, John D AU - Fantner, Georg E AU - Ioerger, Thomas R AU - Walker, Suzanne AU - Bernhardt, Thomas G AU - Rubin, Eric J AU - Rego, E Hesper A2 - Garrett, Wendy S A2 - Kana, Bavesh D A2 - Arthur, Michel VL - 7 PY - 2018 DA - 2018/10/16 SP - e37516 C1 - eLife 2018;7:e37516 DO - 10.7554/eLife.37516 UR - https://doi.org/10.7554/eLife.37516 AB - In most well-studied rod-shaped bacteria, peptidoglycan is primarily crosslinked by penicillin-binding proteins (PBPs). However, in mycobacteria, crosslinks formed by L,D-transpeptidases (LDTs) are highly abundant. To elucidate the role of these unusual crosslinks, we characterized Mycobacterium smegmatis cells lacking all LDTs. We find that crosslinks generate by LDTs are required for rod shape maintenance specifically at sites of aging cell wall, a byproduct of polar elongation. Asymmetric polar growth leads to a non-uniform distribution of these two types of crosslinks in a single cell. Consequently, in the absence of LDT-mediated crosslinks, PBP-catalyzed crosslinks become more important. Because of this, Mycobacterium tuberculosis (Mtb) is more rapidly killed using a combination of drugs capable of PBP- and LDT- inhibition. Thus, knowledge about the spatial and genetic relationship between drug targets can be exploited to more effectively treat this pathogen. KW - Mycobacterium tuberculosis KW - Mycobacterium smegmatis KW - peptidoglycan KW - polar growth KW - rod shape maintenance JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -