Virion proteome of Cafeteria roenbergensis virus strain BV-PW1

This project describes the protein composition of the Cafeteria roenbergensis virus (CroV, strain BV-PW1: TaxID 693272) particle, a giant marine DNA virus that infects the heterotrophic nanoflagellate microeukaryote C. roenbergensis. CroV is a member of the Nucleo-Cytoplasmic Large DNA Virus clade and related to Acanthamoeba polyphaga mimivirus. CroV possesses a DNA genome of ~730 kilobase pairs that encodes 544 predicted proteins. We analyzed the protein composition of purified CroV particles by liquid chromatography - tandem mass spectrometry (LC-MS/MS) and identified 141 virion-associated CroV proteins. Predicted functions could be assigned to 37% of these proteins, which include structural proteins as well as enzymes for transcription, DNA repair, redox reactions and protein modification. Homologs of 36 CroV virion proteins have previously been found in the virion of Acanthamoeba polyphaga mimivirus. This study shows that giant DNA virus particles contain more than one hundred viral proteins that include specific enzymatic functions.