Micropatterning proteins on polyhydroxyalkanoate substrates by using the substrate binding domain as a fusion partner

A novel strategy for micropatterning proteins on the surface of polyhydroxyalkanoate (PHA) biopolymer by microcontact printing (microCP) is described. The substrate binding domain (SBD) of the Pseudomonas stutzeri PHA depolymerase was used as a fusion partner for specifically immobilizing proteins on PHA substrate. Enhanced green fluorescent protein (EGFP) and red fluorescent protein (RFP) fused to the SBD could be specifically immobilized on the micropatterns of poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate). Laser scanning confocal microscopic studies suggested that two fusion proteins were micropatterned in their functionally active forms. Also, antibody binding assay by surface plasmon resonance suggested that protein-protein interaction studies could be carried out using this system.