L. Hathaway (Pneumococcal biology)
Streptococcus pneumoniae is an important human pathogen capable of causing bacterial meningitis and pneumonia but can also be a harmless colonizer of the human nasopharynx. Our research is currently focussed on two main areas: peptide mediated communication between pneumococci and other bacterial species and the role of serotype in pneumococcal biology and disease.
In nature, most bacteria live in multi-species communities known as microbiota but interactions between bacterial species are under studied. We have found that two proteins of nonencapsulated S. pneumoniae, AliB-like ORF 1 and ORF 2, bind specifically to peptides matching other bacterial species (Enterobacteriaceae and Prevotella respectively). This results in changes in competence for genetic transformation and ability to colonize the nasopharynx. We are pursuing this research to determine the wider implications for communication between bacterial species.
Virulence of pneumococcal serotypes
Pneumococci may express one of more than ninety different polysaccharide capsules, or express no capsule. This variation is used to characterize the bacteria into serotypes some of which are predominantly associated with harmless colonization of the nasopharynx whilst others are more commonly associated with invasive disease. We are studying the role of serotype in pneumococcal biology and host response using capsule switch mutants of clinical isolates.