Nitrile Hydrolysing Enzymes-Producing Bacterium Isolated from Gandang Dewata Mountain, West Sulawesi

Abstract

Nitrile compounds are widely used and manufactured by the chemical industry for synthesis of important compounds. They are known to be highly toxic because of the CN group onits the molecular structure and most of them are hydrophobic, mutagenic and carcinogenic. Nevertheless, some microbes were reportedly able to hydrolyse nitrile by involving nitrile-hydrolysing enzymes, such as nitrilase, nitrile hydratase and amidase. Nowadays, the application of these enzymes is increasingly recognized because it may be used as a biocatalyst to produce some of important pharmaceutical compounds and/or synthetic chemical that has high economic values. These enzymes also have a significant role in environmental protection due to their capability to eliminate toxic compounds. The probability to acquire potential microbes-degrading nitriles in nature and extreme environments is extremely high. Some bacteria have been isolated from Gandang Dewata mountain areas. SB1D1 bacterial isolate was identified as Rhodococcus pyridinivorans. It showed potential activity as bacteria-hydrolysing nitrile. The bacteria was able to grow on CH3CN (acetonitrile) until the concentration of 1000 mM and also it was demonstrated to degrade 50 mM C6H5-CN (benzonitrile) and produced benzamide, benzoic acid even in low concentrations. SB1D1 isolate is a gram-positive bacterium and the colonies are light orange in colour. Based on the literature review, it is known that R. pyridinivorans studied detail and usually used for bioremediation agent to degrade toxic compounds, such as pyridine, PAH etc.Therefore,R. pyridinivorans strain SB1D1 is a good candidate as nitrile hydrolysing-bacteria for degrading aliphatic and aromatic nitrile.