Isolation and characterization of an iridovirus from Hermann's tortoises (Testudo hermanni)

A virus was isolated from tissues of 2 diseased Hermann's tortoises (Testud o hermanni) and preliminarily characterized as an iridovirus. This conclusi on was based on the presence of inclusion bodies in the cytoplasm of infect ed cells, sensitivity to chloroform, inhibition of virus replication by 5-i odo-2'-desoxyuridine and the size and icosahedral morphology of viral parti cles. The virus was able to replicate in several reptilian, avian and mamma lian cell lines at 28 degrees C, but not at 37 degrees C. Restriction enzym e analysis showed resistance of the viral DNA to digestion With HpaII due t o methylation of the internal cytosine at CCGG sequences. Part of the genom ic region encoding the major capsid protein was amplified by PCR and subjec ted to sequence analysis. Comparative analysis of the obtained nucleotide s equence revealed that the isolate is closely related to frog virus 3, the t ype species of the genus Ranavirus.