ABSTRACT
Phosphatase [APase] enzymes including phytases have broad applications in diagnostic kits, poultry feeds, biofertilizers and plant nutrition. Because of high levels of sequence diversity among phosphatases, an efficient functional screening method is a crucial requirement for the isolation of the encoding genes. This study reports a functional cloning screening method for the isolation of APase-encoding genes from bacterial genomic libraries in a medium containing a chromogenic substrate. The method was optimized to distinguish the desired signal from the background chromosomal APase activity. This screening method led to the isolation of two novel APase-encoding genes from Pseudomonas putida with no similarities to the known genes in the databases, indicating successful implementation of the developed method