Bacteriophage Protein-Protein Interactions

Bacteriophages T7, lambda, P22, and P2/P4 (from Escherichia coli), as well as phi 29 (from Bacillus subtilis), are among the best-studied bacterial viruses. This chapter summarizes published protein interaction data of intraviral protein interactions, as well as known phage-host protein interactions of these phages retrieved from the literature. We also review the published results of comprehensive protein interaction analyses of Pneumococcus phages Dp-1 and Cp-1, as well as coliphages lambda and T7. For example, the approximate to 55 proteins encoded by the T7 genome are connected by approximate to 43 interactions with another approximate to 15 between the phage and its host. The chapter compiles published interactions for the well-studied phages lambda (33 intra-phage/22 phage-host), P22 (38/9), P2/P4 (14/3), and phi 29 (20/2). We discuss whether different interaction patterns reflect different phage lifestyles or whether they may be artifacts of sampling. Phages that infect the same host can interact with different host target proteins, as exemplified by E. coli phage lambda and T7. Despite decades of intensive investigation, only a fraction of these phage interactomes are known. Technical limitations and a lack of depth in many studies explain the gaps in our knowledge. Strategies to complete current interactome maps are described. Although limited space precludes detailed overviews of phage molecular biology, this compilation will allow future studies to put interaction data into the context of phage biology.