Bacteria in heart valves

Graeme Bowles and Steven Lower Staphylococcus aureus (in red) forms a biofilm on implantGraeme Bowles and Steven Lower 

Genetic changes in certain varieties of Staphylococcus aureus lead this bacterium to form biofilms on solid substrates. Thus, the microorganism sticks to and stays on the surface of heart implants and this may cause serious infections in patients. This was discovered by researchers from the United States, Switzerland and Thailand, along with Brazil’s Roberto Lins, from the Federal University of Pernambuco. The researchers used a microscope with atomic force to study the forces that enable the Staphylococcus to adhere to the minerals (PNAS, online on October 24). Additionally, the researchers also produced simulations of molecular dynamics to understand better which proteins of the infectious bacteria enable them to adhere to implants. At the end of their research studies, the scientists gathered evidence showing that at least three mutations caused the formation of biofilms on implants.