Fig. 1. PCR for detection of Megalocytivirus and discrimination of red sea bream iridovirus and epizootic haematopoietic necrosis virus. The iridovirus from dwarf gourami (DGIV-2004), red sea bream iridovirus (RSIV) and epizootic haematopoietic necrosis virus (EHNV) were tested in PCR with Megalocytivirus genus-specific MCP primers C50/C51, MCP primers for the DGIV-group within Megalocytivirus C82/C83 and MCP primers for EHNV M151/M152. LM, molecular size marker (bp); in each panel: lane 1, RSIV; lane 2, MCIV; lane 3, DGIV-2004; lane 4, EHNV; lane 5, water control; lane 6, PCR mix control.

Fig. 2. Unrooted consensus bootstrap phylograms of megalocytiviruses for (A) MCP gene over 1362 bp and (B) ATPase gene over 563 bp prepared using the neighbour joining distance method. Bootstrap percentage values are shown adjacent to lines; the scale bar indicates distance as a proportion of nucleic acid substitutions. The viruses and sources are described in Table 1.

Megalocytivirus samples and sequences used in this study

Primers used in this study

Prevalence of Megalocytivirus infection in diseased gouramis from aquarium shops in Sydney

Fish were tested for Megalocytivirus MCP nucleic acid using PCR with primers C50/C51.

Other finfish tested for Megalocytivirus MCP nucleic acid by PCR analysis with primers C50/C51

Homology between the MCP nucleotide sequence of MCIV and viruses in recognized iridoviral genera and an unclassified iridovirus

Percent homology of MCP nucleotide and amino acid sequences

Nucleotide homology is provided to the left of the asterisks while amino acid homology is provided to the right. RSIV-S is sequenced included as a control, Nucleotide homologies were determined over ^a1362 bp and ^b259 bp while amino acid sequence homologies were determined over ^c454 residues and ^d85 residues.

Percent homology of ATPase nucleotide and amino acid sequences

Nucleotide homology is provided to the left of the asterisks while amino acid homology is provided to the right. RSIV-S is sequenced included as a control, Nucleotide homologies were determined over ^a1871 bp, ^b1766 bp, ^c1705 bp, ^d145 bp, ^e1714 bp, ^f1557 bp, ^g1488 bp, ^h1696 bp and ⁱ1668 bp while amino acid homologies were determined over ^j239 residues and ^k5 residues.

Percent homology of RNA polymerase nucleotide and amino acid sequences

Nucleotide homology is provided to the left of the asterisks while amino acid homology is provided to the right. Nucleotide homologies were determined over ^a789 bp, ^b675 bp and ^c654 bp while amino acid homologies were determined over ^d100 residues, ^e62 residues and ^f55 residues.

Percent homology of DNA polymerase nucleotide and amino acid sequences

Nucleotide homology is provided to the left of the asterisks while amino acid homology is provided to the right. Nucleotide homologies were determined over ^a378 bp, ^b290 bp while amino acid homologies were determined over ^c98 residues and ^d49residues.

Percent homology of IRB6 nucleotide sequences

Homologies were determined over ^a823 bp, ^b706 bp, ^c713 bp and ^d678.

Percent homology of CY15 nucleotide sequences

Homologies were determined over ^a500 bp, ^b405 bp, ^c129 bp and ^d128 bp.