Ocean-dwelling bacterium produces hydrogen

Nature : Himadri Pakrasi of Washington University in St. Louis and his collaborators have discovered that the photosynthesizing bacterium Cyanothece 51142 makes hydrogen. The enzyme responsible, nitrogenase, is present in other bacteria, which, like Cyanothece 51142, use it to make ammonia and its byproduct, hydrogen. Because nitrogenase breaks down in the presence of oxygen, those other bacteria have to live in oxygen-poor environments. Cyanothece 51142, by contrast, consumes the oxygen within its cell walls during photosynthesis. The ability of Cyanothece 51142 to live in oxygen-rich environments could make it a useful source of hydrogen fuel for cars and other machines.