Two General Methods for the Isolation of Enzyme Activities by Colony Filter Screening

Christian Heinis,Samu Melkko,Salvatore Demartis,Dario Neri Press enter key for correspondence information Press enter key to Email the author

Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland

Abstract

We describe two general methodologies, based on filter-sandwich assays, for isolating enzymatic activities from a large repertoire of protein variants expressed in the cytoplasm of E. coli cells. The enzymes are released by the freezing and thawing of bacterial colonies grown on a porous master filter and diffuse to a second “reaction” filter that closely contacts the master filter. Reaction substrates can be immobilized either on the filter or on the enzyme itself (which is then, in turn, captured on the reaction filter). The resulting products are detected with suitable affinity reagents. We used biotin ligase as a model enzyme to assess the performance of the two methodologies. Active enzymes were released by the bacteria, locally biotinylated the immobilized target substrate peptide, and allowed the sensitive and specific detection of individual catalytically active colonies.

http://www.cell.com/cell-chemical-biology/abstract/S1074-5521(02)00113-8

Thank you very much Ali Aldallal. I will explore this option for coagulase and lipase isolation.

hello Monsi,

The strain possessing the highest lipase activity could be identified by both biochemically and sequencing of 16S rRNA gene

You can use Lysostaphine