The rod-like shape of bacteria, like Bacillus subtilis depicted here, is the result of carefully directed synthesis of peptidoglycans, the macromolecular materials that make up the sturdy, protective bacterial cell wall. In healthy bacteria, anisotropic peptidoglycan synthesis prevails, leading to the characteristic and very common rod-shaped appearance.

It was already known that teichoic acids on the bacterial surface play an essential role in ensuring rod-like growth, but the underlying mechanism was unclear. A team led by Felix Barber, at the time a postdoc at New York University and currently assistant professor at Ohio State University, applied a combination of microscopy and laser tracking of individual molecules, dubbed ‘in situ biochemistry’, to unravel teichoic acid involvement.

Their results show that wall teichoic acids have a double role. Their presence ‘paves’ the bacterial surface by enabling the so-called Rod complexes to form a strong network that acts like a girdle to maintain the rod-like shape. Eliminating teichoic acids leads to a quick increase in nanopore formation which in turn hinders cross-coupling of the Rod complexes and thus weaking of the cell wall and loss of structure.

In addition, teichoic acids also regulate the levels of two proteins that promote isotropic peptidoglycan synthesis, leading to peptidoglycans that grow in all directions, which results in amorphous, blob-shaped bacteria. And that offers new clues for the development of antibiotics or for re-sensitizing currently resistant strains. Targeting teichoic acids might be a promising route to weakening the defensive walls of pathogenic bacteria.  

F. Barber, et al., Wall teichoic acids regulate peptidoglycan synthesis to maintain rod shape in Bacillus subtilis, Nature Microbiology (2026), doi:10.1038/s41564-026-02368-6