CHARACTERIZATION AND MORPHOLOGY OF THE BLUEGILL VIRUS

An enveloped, ether-sensitive, acid-labile virus isolated from Lepomis macrochirus, the bluegill, is described. Virus replication is limited to teleostean cell lines and achieves highest titres in centrachid cells. As determined by the uptake of tritiated nucleotides and the effect of 6-azauridine and actinomycin D on replication, the virus genome is RNA. The virus has no haemagglutinin or neuraminidase nor does it share antigens with prototypes of orthomyxoviruses, paramyxoviruses or arena-viruses. Thin-section electron microscopy reveals a virion 80 to 100 nm in diam. associated with the cell surface and intracellular vacuoles. The virus appears to mature by budding and exhibits a prolonged replication cycle and significant cell-associated infectivity. The time sequence of replication indicates that the prolonged cycle is due to maturation rather than to delayed synthesis of RNA and protein. The bluegill virus (BGV) represents a novel, hitherto undescribed, type of teleostean virus.