Poles of bacteria imaged in fine detail for the first time

For the first time, scientists have captured detailed images of the poles, or ends, of rod-shaped bacteria at a molecular level. Researchers from UCL and the University of Oxford used a new technique to keep live bacteria attached to a glass surface, allowing them to be imaged without moving. Atomic force microscopy, which uses a tiny probe to gently tap the bacterial cell, provided a much higher resolution than traditional light microscopy.

Imaging the bacterial poles is akin to "opening a view of the back of the moon," as senior author Professor Bart Hoogenboom explained. Poles are where cells divide and contain crucial information about this process, and they may also be a prime target for antibiotics. The method of immobilizing the cells without affecting their growth and reproduction enabled researchers to study a wider range of live bacteria than previously possible, which could help understand differences between species and antibiotic resistance.

Lead author Dr. Anna Scheeder noted that the immobilization method opens up exciting possibilities for studying bacterial surfaces more reliably and observing nanoscale differences that were previously challenging to assess. The team found that the poles of rapidly dividing bacteria had fold-like defects, while less active bacteria had smoother ends, suggesting that this part of the cell may not have fully remodeled after division.

Additionally, E. coli, Pseudomonas aeruginosa, and Acinetobacter baumannii, which lack the network of little holes (pores) found in E. coli, had different antibiotic responses and resistance mechanisms.