gpD Stabilizes the head shell following the rearrangement of the gpE subunits of the head shell lattice that accompanies expansion of the head. There are approximately 420 copies of protein D per mature phage. Major capsid protein D D MTSKETFTHYQPQGNSDPAHTATAPGGLSAKAPAMTPLMLDTSSRKLVAWDGTTDGAAVGILAVAADQTSTTLTFYKSGTFRYEDVLWPEAASDETKKRTAFAGTAISIV 110 VCAD_LAMBD Head decoration protein