Our project aim increased the degradation of fatty acid (Beta oxidation pathway) in Shewanella putrefaciens. So, we choose 2 methodologies to do that. 1° inhibition of the FadR expression (fatty acid metabolism regulator protein) The beta-oxidation is not a constituve pathway but with the mutation of the transcription factor, FadR, which functions as a switch that co-ordinately regulates the machinery required for fatty acid beta-oxidation, we hope turn this pathway constituve. To increased the degradation of fatty acid by S. Putrefaciens. 2° Increase the FadL and FadD expression. Our second step in genetic engineering of Shewanella is overexpression of two important genes for beta oxidation : (1) The FadL, Long-chain fatty acid outer membrane transporte, is a gene of fatty acid transport protein, outer membrane; long-chain fatty acid receptor to enhance the long chain fatty acids intake by Shewanella putrefaciens and (2) The FadD, Long-chain-fattyacid-CoA ligase, ligates CoA in fatty acid chain preparing it to get into the Beta-Oxidation metabolic pathway. These overexpression will increased B-oxidation and therefore ATP, H+ and electrons production.