Identification of the ciliate associated with Brown Band disease in corals by the use of microscopic and molecular approaches.Three disease samples were collected from Davies Reef (n=3) in the central sector of the Great Barrier Reef and one from the fringing reefs around Heron Island in the southern sector. All samples were taken from near the advancing front of the disease lesion and encompassed the brown band ciliate mass.Total DNA from ciliate and coral tissue samples was extracted and amplified with conserved eukaryotic primers (18S-6-CIL-V and 18S-1511-CIL-R). PCR resulted in amplification of the 18S rRNA genes from protozoa and other eukaryotic organisms, with the products cloned and the insert 18S rRNA gene reamplified from individual clones.Phylogeny is described between the 18S rRNA gene ciliate clone sequence obtained from a sample of the coral Acropora muricata infected with Brown Band disease and chosen reference ciliate sequences inferred by maximum-likelihood analysis.The ciliate was identified as a new species belonging to the class Oligohymenophorea, subclass Scuticociliatia. The nucleotide sequence data have been submitted to the GenBank nucleotide sequence database under accession number AY876050.
Identifying the microbial communities associatedwith coral diseases is critical to further current understanding of how environmental and climate changes might affect the prevalence of diseases.
The phylogeny tree for the Brown Band Ciliate contains the following (GenBank accession number in brackets):Alexandrium tamarense (AF022191), Amphidinium belauense (L13719), Anophyroides haemophila (U51554), Babesi rodhaini (M87565), Blepharisma americanum (M97909), Cohnilembus verminus (Z22878), Colpoda inflate (M97908), Crypthecodinium cohnii (M34847), Eufolliculina uhligi (U47620), Euplotes aediculatus (AF1641360), Isopora belli (AF106935), Mesanophrys carcini (AY103189), Metanophrys similis (AF452709), Neospara caninum (U16159), Oxytricha sp. (AF164126), Paranophrys magna (AY103191), Parauronema longum (AY212807), Prorocentrum micans (M14649), Prorodon teres (X71140), Pseudocohnilembus marinus (Z22880), Sarcocystis muris (M34846), Schizocaryum dogieli (AF527756), Stentor coerulus (AF357145), Symbiodinium microadriaticum (M88521), Theileria annulata (M34845), Toxoplasma gondii (X75429), Unidentified coral symbionts Type N (AF238264, AF238265, AF238266), Uronema marinum (Z22881).
