Cyanides are fast-acting poisons, can be lethal if exposed in excess. In spite of fact, cyanides are discharged as effluents in large scale from industries every year. Certain bacteria, fungi, algae and plants produce cyanides. It has been observed that microbes and plant systems can degrade cyanides to less toxic compounds. There are many enzymes, which are produced by microorganisms that utilize cyanides as substrate to make alanine, glutamic acid, alfa-amino-butyric acid, beta-cyanoalanine, etc. Present paper deals with different enzymes, their mechanisms and corresponding pathways with respect to the known biochemistry of enzyme and feasibility for the use in treatment of cyanides containing industrial effluents. (C) 2009 Elsevier B.V. All rights reserved.