Crude Oil Bioremediation - Genetically Modified Microorganisms for Poly-Aromatic Hydrocarbon Degradation

The process of Bioremediation uses the microorganisms/their enzymes to aid the degradation and removal of contaminants present in the environment. The microbial metabolic ability is used for degradation and removal of environmental pollutants providing an economically safer alternative compared to the rest of physicochemical methodologies. One of the hazardous organic priority pollutants are the Polyaromatic hydrocarbons (PAHs). There are a lot of public concerns and critical environmental challenges in the world because of being carcinogenically toxic and mutagenic properties, their ubiquitous distribution, recalcitrance and their environmental presence. The understanding about harmful effects of PAHs on ecosystems and human health has resulted in an interest of researchers on their degradation. Many types of microbes like bacteria, fungi, and algae are capable to use PAHs as carbon and energy source under aerobic and anaerobic conditions leading to their degradation or transformation. Microbial genetic makeup having genes conceal catabolic enzymes results in PAH-degradation mechanism. From the past twenty years, PAH- biodegradation mechanism, catabolic gene system encoding catabolic enzymes, and adaptation through genetics and regulations have been investigated in detail. This review is to attain an overview of the present knowledge of the genetically modified organisms in crude oil spills using PAH degradation mechanism.