Communities of Microbial Enzymes and Biodegradation of Persistent Environmental Pollutants

Abstract

Enzymes are biocatalysts that potentiate the rate of substrate conversion into products. They are composed of amino acids with one or more polypeptide moieties. Microbial enzymes are the various enzymes of microorganisms' source, which have wide scope of applications in medicine and industries, including the degradation of persistent environmental wastes. Persistent environmental pollutants have become a global environmental and health concern. Owing to the rapid technological advancement and development in industries, large quantities of persistent environmental pollutants are being let out into the ecosystem posing serious threats to living organisms, thereby deteriorating the environment. Several microbial enzymes are widely used in the decomposition of recalcitrant organic and inorganic wastes. Oxidoreductases and hydrolases constitute the major class of microbial enzymes utilized in biodegradation of environmental pollutants; oxygenases, laccases, and peroxidases are the superfamilies of the oxidoreductase class, whereas lipases, cellulases, and proteases constitute the superfamilies of hydrolytic enzymes widely employed for bioremediation. Bioremediation involves the use of enzymes of microbial origin or the whole cell in the breakdown or transformation of environmental pollutants into less toxic or nontoxic products. Polymeric compounds such as polyethylene, polypropylene, polystyrene, polyvinyl chloride (PVC), polyurethane (PUR), and polyethylene terephthalate (PET) have been degraded using microbial enzymes. The biodegradation process is, however, often impeded due to the incapability of microbial enzymes to hydrolyze the functional groups present.