Prospect of H2 gas Production on an enhanced scale from E. coli
In an article entitled, "Metabolic engineering to enhance bacterial hydrogen production," published in Microbial Biotechnology 1(1): 30–39, a team of three scientists led by Professor Thomas K. Wood at the Artie McFerrin Dept of Chemical Engineering, Texas A&M University, College station, TX demonstrated that it is possible to direct the metabolic flux toward enhancing hydrogen production 141 times. They achieved this seemingly impossible task by using isogenic E. coli K-12 KEIO library to construct multiple precise deletions in the bacterial genome. The bacterium has three active hydrogenases genes; associated with them are the regulatory genes called the formate hydrogen lyase (FHL) system. Hydrogen is synthesized from formate via hydogenase 3 at an accelerated rate. The above scientists altered the regulation of FHL. Several mutated genes such as fdnG, fdoG, narG, focA, fnr and focB mutations took part in re-directing formate metabolism, thereby removing hydrogen consumption by dehydrogenases. The newly created bacterium was christened BW25113 hyaB hybC hycA fdoG/pCA24N-FhlA. The strain produces the largest amount of hydrogen to date matching theoretical yield for hydrogen from formate. Furthermore, in the genetically modified bacterium, the yield of hydrogen from glucose increased by 50%. Wood's experiment has brightened the prospect of utilization of renewable hydrogen fuel at a comparatively low cost. Successful pilot experiment will pave the way of production of hydrogen fuel on a commercial scale mitigating the current suffering of people dependent solely on fossil fuel. Here is one area in which NRB biotechnologists can collaborate with their counterparts in producing clean hydrogen gas for the country at a competitive price.
