Planctomycetes do possess a peptidoglycan cell wall

Abstract

Most bacteria contain a peptidoglycan (PG) cell wall, which is critical for maintenance of shape and important for cell division. In contrast, Planctomycetes have been proposed to produce a proteinaceous cell wall devoid of PG. The apparent absence of PG has been used as an argument for the putative planctomycetal ancestry of all bacterial lineages. Here we show, employing multiple bioinformatic methods, that planctomycetal genomes encode proteins required for PG synthesis. Furthermore, we biochemically demonstrate the presence of the sugar and the peptide components of PG in Planctomycetes. In addition, light and electron microscopic experiments reveal planctomycetal PG sacculi that are susceptible to lysozyme treatment. Finally, cryo-electron tomography demonstrates that Planctomycetes possess a typical PG cell wall and that their cellular architecture is thus more similar to that of other Gram-negative bacteria. Our findings shed new light on the cellular architecture and cell division of the maverick Planctomycetes.

Global and Targeted Lipid Analysis of Gemmata obscuriglobus Reveals the Presence of Lipopolysaccharide, a Signature of the Classical Gram-Negative Outer Membrane

“…Most recently, the detection of peptidoglycan in the cell wall of planctomycetes, including G. obscuriglobus (16,17), supports the interpretation of the G. obscuriglobus cell plan as Gram negative. The absence of peptidoglycan and presence of a proteinaceous cell wall (18) had long been distinguishing planctomycete features that led to the proposal of a unique cell plan for all planctomycetes (3,5,6,13,19).…”

“…The pursuit of this question, together with studies of the structural connections between the LPS of G. obscuriglobus (and possibly other planctomycetes) and the newly discovered planctomycete peptidoglycans (16,17), will shed more light on what is now emerging as the planctomycete variation on the Gram-negative cell plan (20). …”

“…The tentative representative structure (Fig. 7) shows an example of FA distribution, with linked FAs with carbon numbers 16,14,16,14,18, and 18 (a total of 96 carbon atoms, plus 18 carbon atoms in the trisaccharide backbone, for a total of 114 carbon atoms). This tentative structure comprises contributions from three of the most abundant 3-OH FAs detected in our GC-MS measurements, n-C 14:0 , n-C 16:0 , and n-C 18:0 .…”

Outcome after carpal tunnel release: impact of factors related to metabolic syndrome

“…However, their impact on outcome after surgical treatment of CTS is not known. A recent case-control study [7] suggested that metabolic syndrome is related to more severe forms of CTS, as well as to longer recovery time after OCTR, but not to worse improvement after surgery.…”

Bacterial physiology: Life minus Z

“…Suddenly, one imagines the natural evolution of walled FtsZ-less bacteria as perhaps a rather pedestrian affair. In fact, it is not so hard to imagine coli-flowering as a clumsy prelude to the budding-mode of propagation common amongst the walled FtsZ-less Planctomycetes 14, 15 . Allowing CFL mutants to further evolve under various conditions might be enlightening as well as entertaining.…”