2014 AGRO FOOD INDUSTRY HI-TECH 2014 25(卷), 4(期), (53-55页)
Eight bacterial strains showing aspartase activity were isolated from the semi-arid soil samples of the Laguna region of North-East Mexico, using a selective culture medium with ammonium fumarate as an inducer for the production of aspartase. The enzyme activity of the strains was determined by the consumption of ammonium fumarate 0.5 M, pH 8.0 and 37 degrees C. From the eight strains, ASP1 and ASP3 strains showed the highest specific enzyme activity (U/mg of protein), and were used for further studies and their molecular characterization. The production of aspartic acid by these strains was confirmed by paper chromatographic analysis. In order to identify the bacterial strains, primers specific to aspartase were used to amplify a conserved region of 430 bp. The amplicons were sequenced by the Sanger method and ASP3 and ASP1 strains were identified as Acinetobacter calcoaceticus PHEA-2 by BLAST search.