An in vitro microfluidic approach to generating protein-interaction networks

Abstract
A combination of in vitro protein synthesis and microfluidics is used to measure protein-protein interactions between 43 proteins in Streptococcus pneumoniae. The method does not require expression within cells and is amenable to large-scale experiments. We developed an in vitro protein expression and interaction analysis platform based on a highly parallel and sensitive microfluidic affinity assay, and used it for 14,792 on-chip experiments, which exhaustively measured the protein-protein interactions of 43 Streptococcus pneumoniae proteins in quadruplicate. The resulting network of 157 interactions was denser than expected based on known networks. Analysis of the network revealed previously undescribed physical interactions among members of some biochemical pathways.