Cytomegalovirus (CMV) (human herpesvirus 5) glycoprotein B, also referred as CMV gB or gB, which belongs to the herpesviridae glycoprotein B family. It is a 97-amino acid glycoprotein encoded by the ORF of UL55. Cytomegalovirus Glycoprotein B protein is the most abundant component of the envelope, a target of neutralizing antibodies with at least two defined neutralizing epitopes and an essential replication component. Cytomegalovirus Glycoprotein B protein plays important roles in HCMV entry, cell-cell spread of internal virions, and fusion of infected cells. In addition, Cytomegalovirus Glycoprotein B protein is one envelope protein capable of heparin binding. It forms a physical association with host cell annexin II independent of the presence of calcium.