Commensal as well as pathogenic bacteria express proteins that enable them to colonize the continually flushed mucous membranes of mammals. Working with undergraduate students, Dr Okeke will undertake genetic and functional analyses of Escherichia coli agglutinins, a family of bacterial surface proteins hypothesized to be involved in colonization. Agglutinin-like genes are present in the genomes of a wide range of bacterial species, including symbionts and pathogens of nematodes, arthropods and mammals. Therefore knowledge of the role played by E. coli agglutinins in colonization could provide insight into many ecosystems where eukaryotic and prokaryotic cells interact. Agglutinin-encoding genes are especially common in enteroaggregative E. coli (EAEC), hyperadhesive strains that are defined by their ability to adhere to epithelial cells in a characteristic stacked-brick pattern. The contribution of agglutinins to colonization phenotypes seen in EAEC, will be investigated by creating and characterizing isogenic agglutinin gene mutants in models of colonization. Comparative studies of agglutinin genes and gene products, from EAEC and other E. coli strains, will also be conducted to improve the understanding of the function and regulation of this family. These studies of agglutinin gene expression and function will improve the understanding of, and introduce undergraduates to, the biology of eukaryotic hosts and their prokaryotic colonizers
