Targeting the tiniest divide: new research reveals potential vulnerability in bacterial reproduction

By Béatrice St-Cyr-Leroux Mar 30th, 2026

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In 5 seconds An Université de Montréal study finds a previously unknown mechanism in bacterial reproduction that could be attacked by future antibiotics.

A new study shows that bacteria actually strengthen the septum during the final moments of cleavage by a previously undetected mechanism.
Photo : Getty

Bacteria reproduce by dividing into two: they form a wall, or septum, between the two future cells while remodelling the old cell walls so the so-called "daughter" cells can separate without bursting.

Until now, scientists believed that once the dividing wall was built, bacteria gradually break down the links between its two sides to allow the cells to separate in a process called cleavage.

However, a new study published in Nature Communications shows that bacteria actually strengthen the septum during the final moments of cleavage by a previously undetected mechanism.

The study was led by Yves Brun, a professor in the Department of Microbiology, Infectiology and Immunology at Université de Montréal and holder of the Canada 150 Research Chair in Bacterial Cell Biology.

Yves Brun, professor in the Department of Microbiology, Infectiology and Immunology at Université de Montréal
Photo : Université de Montréal

Unknown phase 2 of cell wall construction

Using an advanced microscope and fluorescent dyes that colour the sites of septum formation, Brun and his team discovered that bacteria launch a second phase of cell wall reinforcement at the very moment the two cells begin to divide.

“Instead of building new material from scratch, the cells form cross-links in the existing wall and reinforce it at the precise moment of cleavage,” Brun explained.

The research team identified two key enzymes that work together during this step: one that cleaves the wall to allow separation and another that stitches the wall back together to reinforce the new cell edges.

“It’s a bit like renovating a building while removing a load-bearing wall,” explained Vaidehi Patel, a postdoctoral fellow in Brun’s lab and first author of the study. “You don’t just tear down the wall and hope for the best. You add temporary supports and reinforce the structure at the same time. Bacteria do something similar to protect themselves during division.”

Promising avenue for new antibiotics

Many existing antibiotics, including penicillin and related drugs, work by interfering with the cell division process.

By identifying two enzymes instrumental in cleavage, this new study could lead to new targets for antibiotics, the researchers believe. Disrupting the coordination between these enzymes could prevent proper cell separation, leaving the cells stuck together in chains.

“This work broadens our understanding of how bacterial cells survive the stress of division,” said Patel. “By identifying new molecular players in this process, we are paving the way for alternative strategies to block bacterial growth, particularly in the case of pathogens that are becoming resistant to existing drugs.”

Broader implications

While the study focuses on Bacillus subtilis, a bacterium that has been extensively studied in the laboratory, the researchers believe the same principles can be applied more generally to many Gram-positive bacteria, a family that includes a number of pathogens dangerous to humans.

“As antibiotic resistance continues to increase around the world, these findings provide essential insights for the design of a new generation of treatments that bacteria will find more difficult to circumvent,” Brun concluded.

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