earticle

영어

Nitrilase is one of the enzymes which has been studied from the beginning of the biotechnology era. Because of the simple and mild reaction condition and useful functionality of carboxylic acid group, its ability to convert cyanide group to carboxylic group was of interest to industry, and as a result of such industrial interest, many results were reported and actually applied to industry like polyacrylamide synthesis.(1,2). Nowadays, nitrilase, especially arylacetonitrilase, is coming into spotlight again as a promising biotool to synthesize optically pure alpha-hydroxy acid. Alpha-hydroxy acid is industrially very promising compound. Because, its structure is similiar with natural amino acid structure. To find nitrilase activity, enrichment culture system has been mainly used as a screening method using cyanide compounds of interest as a sole N-source (6, 7, 8). However, because there are always some limitations of enrichment process, like instability of cyanide compounds or the limited species , like alcaligense, pseudomonas found, finding new enzyme using this old-fashioned method doesn't seem to be promising. Faced with this obstacle, other screening tools were investigated as a alternative, and metagenome (9) ,
bioinformatics (10,11) has showed results and possibility so far. We report the new enzyme screened from NCBI DB via bioinformatics tools. Using profile analysis based on nitrilase sequence database, one of putative nitrilase was given the most probability, and over-expressed in E.coli heterologously.and purified using N-terminal His-tag separation. Recombinant enzyme shows good activity toward mandelonitrile, which means it belongs to arylacetonitrilase subgroup, and proves to be good partner for synthesis of stereospecific mandelic acid combined with stereospecific oxynitrilase.