Characterization of the Proteins Associated with Caulobacter crescentus Bacteriophage CbK Particles.

Bacteriophage genomes contain an abundance of genes that code for hypothetical proteins with either a conserved domain or no predicted function. The Caulobacter phage CbK has an unusual shape, designated morphotype B3 that consists of an elongated cylindrical head and a long flexible tail. To identify CbK proteins associated with the phage particle, intact phage particles were subjected to SDS-PAGE, and the resulting protein bands were digested with trypsin and analyzed using MALDI mass spectroscopy to provide peptide molecular weights.