Abstract
This chapter describes a system for analyzing both homo- and heterodimerization of full-length proteins and protein fragments in an Escherichia coli background. The characterization of protein-protein interactions can reveal much about the structure and function of individual proteins and protein complexes. Many methods designed to identify these interactions have been reported, including yeast two hybrid and plasmid-based bacterial systems. This system has been successful in determining interactions between proteins involved in the biosynthesis of the polysialic acid capsule of E. coli K1. These interactions include those between full-length proteins as well as those between full-length proteins and protein fragments. However, it is not necessary to restrict the system's use to studying only Escherichia coli protein interactions. Another feature of this system is that the detection of interaction between fusions is not disrupted by the tandem expression of unfused subunits in the host strain. Chloramphenicol acetyltransferase (CAT) fused to the wild-type LexA DNA binding domain(DBD) efficiently repressed lacZ transcription in SU101, even though this strain carries a transposon that expresses subunits of the same type I CAT. This data also illustrates that some multimeric proteins can be studied using this system, since CAT is a well-characterized homotrimer.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call