The Streptococcus pneumoniae cell wall is mostly composed of peptidoglycan, a macromolecule forming an intricate 3D mesh of fibres and pores on the outer layer of all gram-positive bacteria. It is essential for cell survival and specific, making it a great target for antibiotics and new approaches alike. One possibility for non-antibiotic alternatives might be enzymes involved in peptidoglycan maturation. If the cell wall cannot mature the bacteria cannot divide. This project will explore mutant strains involved in peptidoglycan maturation using atomic force microscopy (AFM) and stochastic optical reconstruction microscopy (STORM). The student will perform growth and kill curves for two mutant strains and compare them to the Streptococcus pneumoniae wild type (WT); the student will learn the basics of AFM and STORM to obtain robust microscopy data to compare between at least one mutant and the WT. Additionally, the student will help develop a new sample preparation protocol that will allow us to directly visualise the peptidoglycan maturation process, providing unprecedented resolution (on the order of 2-5 nm) of this dynamic process, in vivo. Students will need to find their own accommodation and be expected to present their findings orally at a research day in York in September 2025.