Vaccines: New way to tame a virus

A live, genetically modified flu virus can infect animals and trigger a strong immune response, but cannot multiply in its host’s cells. Such modified viruses could one day be used to improve on current vaccines (pictured).Vaccines made of live viruses elicit stronger

Catalysts: Silicon added to life’s toolbox

Molecules containing both carbon and silicon have become a standard part of synthetic chemistry, but life uses silicon only in inorganic compounds such as the shells of diatoms.Now, Frances Arnold and her collaborators at the California Institute of Technology in Pasadena have engineered bacteria