Science Cafe 9/5/18

On Wednesday our very own Dr Richard Silverman from the biology department gave a very interesting talk about his research into Cystic Fibrosis in Canada prior to becoming a teacher. Cystic fibrosis (CF) is a genetic disorder that is a result of a mutation in the CFTR gene that codes for chloride channels which are responsible for the movement of Cl- ions and thus water. CF is caused by a recessive allele which disrupts the normal function of the channel found in all cell membranes thus mucus-producing cells secrete thick and sticky mucus. CF causes an increase in bacterial infections such as Pseudomonas aeruginosa and Staphylococcus aureus which are two infections that Dr Silverman focussed on. He explained how exploring two infections was quite unusual as most scientists focus on one infection at a time, however, after noticing a pattern in which CF patients had over a 60% prevalence of having a S.aureus infection when children but that decreases as they grow older and in comparison a prevalence of around 20% for children for a P.aeuginosa infection which rises to over 70% as they grow older, with a peak at 25-34 year olds. Dr Silverman went on to describe his experiments with these two bacteria and discovered that Staphylococcus inhibits Pseudomonas as when added together, contrary to expectations, inflammatory response of pseudomonas decreases. The research team then decided to find out how this inhibition worked and after further experiments they noticed that Staphylococcus inhibits one particular TLR signalling protein on the cell membrane by releasing an exotoxin called hemolysin, thus stopping the signal cascade that would normally occur. This was a really thought-provoking and at times amusing Science Café talk that stimulated the minds of all future researchers.