Identification and comparison of RCMV ALL 03 open reading frame (ORF) among several different strains of cytomegalovirus worldwide.

BACKGROUND: Rat cytomegalovirus ALL-03 (Malaysian strain) which was isolated from a placenta and uterus of a house rat, Rattus rattus diardii has the ability to cross the placenta and infecting the fetus. To further elucidate the pathogenesis of the Malaysian strain of Rat Cytomegalovirus ALL-03 (RCMV ALL-03), detailed analysis on the viral genome sequence is crucial. METHODS: Genome sequencing of RCMV ALL-03 was carried out in order to identify the open reading frame (ORF), homology comparison of ORF with other strains of CMV, phylogenetic analysis, classifying ORF with its corresponding conserved genes, and determination of functional proteins and grouping of gene families in order to obtain fundamental knowledge of the genome. RESULTS: The present study revealed a total of 123 Coding DNA sequences (CDS) from RCMV ALL-03 with 37 conserved ORF domains as with all herpesvirus genomes. All the CDS possess similar function with RCMV-England followed by RCMV-Berlin, RCMV-Maastricht, and Human CMV. The phylogenetic analysis of RCMV ALL-03 based on conserving genes of herpes virus showed that the Malaysian RCMV isolate is closest to RCMV-English and RCMV-Berlin strains, with 99% and 97% homology, respectively. Similarly, it also demonstrated an evolutionary relationship between RCMV ALL-03 and other strains of herpesviruses from all the three subfamilies. Interestingly, betaherpesvirus subfamily, which has been shown to be more closely related with gammaherpesviruses as compared to alphaherpesviruses, shares some of the functional ORFs. In addition, the arrangement of gene blocks for RCMV ALL-03, which was conserved among herpesvirus family members was also observed in the RCMV ALL-03 genome. CONCLUSION: Genomic analysis of RCMV ALL-03 provided an overall picture of the whole genome organization and it served as a good platform for further understanding on the divergence in the family of Herpesviridae.

Isolation and phylogenetic analysis of caprine Orf virus in Malaysia.

Orf virus is a DNA virus that causes contiguous ecthyma in goat and sheep. Infection of animals with this virus cause high mortality in young animals resulting in huge economic losses. In this study, we investigated an outbreak of Orf in a goat farm in Malaysia. Samples were collected from infected animals and viral isolation was done using both LT and MDCK cell lines. Molecular detection was done by conventional PCR for specific primers; B2L and F1L genes and phylogenetic analysis was done on the sequence data obtained. Cytopathic effects (CPE) were observed in both cell lines after 3 days of inoculation and were 50 % by the sixth day. PCR showed positive bands for both B2L and F1L genes and phylogenetic analysis showed that the Malaysian strain had close homology to the Chinese and Indian Orf virus isolates. This study gives more insight into the existing Orf viral strains in Malaysia and their relationship with other strains globally.