Understanding nitrile-degrading enzymes: classification, biocatalytic nature and current applications

Abstract

Abstract Nitrile-degrading enzymes commonly known as nitrilase enzymes are able to metabolize nitrile-substituent compounds and they have several industrial applications, for example: in drugs synthesis. It is also common to observe their exploitation for obtaining chemical compounds with commercial interests related to cosmetics production, paints and additives. In addition, these are frequently used in the active metabolites synthesis of pesticides. Due to the catalytic nature of such proteins, it is possible to take advantage of their biotechnological potential to be applied in various scientific fields including synthetic biocatalysis and environmental remediation, since they have been successfully used for soils nitrile-wastes decontamination such as cyanide, bromoxynil and benzonitrile. On the other hand, these enzymes are considered very important intermediaries of metabolic pathways related to indolic compounds that are produced by bacteria, plants and superior fungi, acting in most cases as vegetal growth hormones. Given the fact that indole-derivative molecules play an important role in physiological responses in superior organisms, nitrilase enzymes may be considered as important part of unknown multi-enzymatic secondary metabolites pathways. In light of the above considerations, this review attempts to summarize the current status of nitrilase research and describing in detail the main characteristics of nitrile-converting enzymes with emphasis on fungal proteins, including their function and catalytic selectivity. Likewise, their relationship with plant metabolism and biotechnological importance in bioremediation processes is discussed.