Chloroviruses Have a Sweet Tooth

• Published in: Viruses Vol. 9; no. 4; p. 88
• Main Authors: Van Etten, James L, Agarkova, Irina, Dunigan, David D, Tonetti, Michela, De Castro, Christina, Duncan, Garry A
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 22.04.2017; MDPI
• Subjects: Carbohydrate Metabolism; Carbohydrates; Chlorella - virology; Enzymes; Extracellular matrix; Genes; Genes, Viral; Genomes; Glycoproteins; Hyaluronic acid; Infections; Metabolic Networks and Pathways; Metabolism; Phycodnaviridae - genetics; Phycodnaviridae - physiology; Proteins; Review; Transfer RNA; Viruses; glycan structures; glycan synthesis; chloroviruses; glycoproteins; giant viruses; chitin synthesis; nucleotide sugar synthesis; hyaluronan synthesis
• ISSN: 1999-4915; 1999-4915
• DOI: 10.3390/v9040088

Chloroviruses are large double-stranded DNA (dsDNA) viruses that infect certain isolates of chlorella-like green algae. They contain up to approximately 400 protein-encoding genes and 16 transfer RNA (tRNA) genes. This review summarizes the unexpected finding that many of the chlorovirus genes encode proteins involved in manipulating carbohydrates. These include enzymes involved in making extracellular polysaccharides, such as hyaluronan and chitin, enzymes that make nucleotide sugars, such as GDP-L-fucose and GDP-D-rhamnose and enzymes involved in the synthesis of glycans attached to the virus major capsid proteins. This latter process differs from that of all other glycoprotein containing viruses that traditionally use the host endoplasmic reticulum and Golgi machinery to synthesize and transfer the glycans.