A split-protein sensor for studying protein–protein interaction in mycobacteria

The study of protein function in living cells is an essential complement to genomics, yet method development does not always keep pace with sequencing. Experimental techniques for the genus mycobacteria are relatively underdeveloped, though seventeen genomes have been sequenced. “Split-Trp” is a split-protein sensor used to detect protein–protein interactions in tryptophan auxotrophic Saccharomyces cerevisiae, but the principles behind the sensor should allow it to function in a broad range of microbial hosts. Here we introduce Split-Trp to Escherichia coli and Mycobacterium smegmatis and demonstrate that this system is a simple assay for protein interaction in both organisms.