There's strength in numbers, especially within sheets of bacteria called biofilms. But things get stuffy in biofilms as bacteria struggle to get oxygen. Pseudomonas aeruginosa copes by producing energy using Cco enzymes, oxidases adapted to low oxygen conditions. Cco1 and Cco2 do this using a portion of the enzyme called a catalytic subunit. Researchers grew P. aeruginosa biofilms in dishes and imaged them in 3D (pictured). Biofilms with Cco1 and Cco2 deleted (bottom right) were smaller and thinner than normal (top left). Yet deleting just the catalytic subunits of these enzymes had little effect (top, middle). However deleting another catalytic subunit, CcoN4, weakened the biofilm (top right) and deleting all three catalytic subunits (bottom left) weakened it more. P. aeruginosa therefore preferentially uses the catalytic subunit CcoN4 to support Cco1 and Cco2, making it an attractive target for combating P. aeruginosa infections, which can be fatal in cystic fibrosis patients.
Written by Lux Fatimathas
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