Abstract
In the present study, highest hydrogen production by Rhodobacter sphaeroides was seen in lactose and mannitol as carbon sources. Glutamic acid and tyrosine induced the highest production of hydrogen. Cyanocobalamine induced the highest production of hydrogen. Enhancement of hydrogen production by 23% was seen after knocking out of the hydrogen reuptake hydrogenase gene. Large-scale production of hydrogen can be tried with this genetically engineered organism, provided some safety aspects are taken into consideration, especially with storage as hydrogen explodes when it comes in contact with air.