Many pathogenic bacteria, including Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus, have the ability form biofilms which can provide increased protection from antibiotics and the host immune system and are thus implicated in pathogenesis. Adhesion is one of the first steps in biofilm formation and is mediated by adhesins located on pili or fimbriae on the surface of bacteria. These hair-like appendages are able to recognize and bind to specific receptor moieties on the host cell. FimH, a two-domain protein located at the terminus of the type 1 pili, is an adhesin with a mannose binding pocket located on the end of its lectin domain (Figure ). The FimH gene is detectable in 90% of E. coli strains, and FimH is used by both adherent invasive E. coli (AIEC) and uropathogenic E. A depiction of a) adherent E. coli highlighting both the type 1 pilus and the BtuB (PDB; 3RGM ) receptor on the surface of the bacteria, b) the design of our novel colicin conjugates where a biologically relevant motif is attached by a linker to colicin E9 (PDB; 5EW5 ). The application of these conjugates for c) labelling of the bacterial surface with biologically relevant motifs and d) the initiation of bacteria aggregation when using a mannose linked conjugate. coli (UPEC) to adhere to host cells via terminal mannose units on epithelial glycoproteins. These E. coli strains are well known pathogens, with UPEC responsible for over 80% of uncomplicated UTIs with an estimated yearly health care cost >$1 billion, and AIEC implicated in inflammatory bowel disease in Crohn's disease patients. Antibiotics remain the frontline treatment for these infections, however increasing antibiotic resistance rates coupled with international guidelines advising against the use of antibiotics in Crohn's sufferers means there is an urgent need to develop non-bactericidal treatments against these adhesive bacteria. This has led to a wealth of elegant research into the use of monomeric α-D-mannopyranoside glycans as anti-adhesion therapies that bind to FimH. However, a fundamental limitation of many of these molecules is that they only participate in monovalent binding, whereas in nature carbohydrate ligand presentation is predominately multivalent, and although impressively constructed mannose-based dendrimers typically have higher potencies than their monovalent counterparts, they can also be more challenging to access.