Representative denaturing gradient gel electrophoresis (DGGE) profiles of: ND: non-diseased coral; AH: apparently healthy tissue – the tissue above the advancing lesion on a disease coral; PWS: Progressive White Syndrome [note: from two different species, Acropora muricata and A. aspera, and from two different locations, Heron Island (GBR) and the Solomon Islands]; and BrB: Brown Band Disease; (A) bacterial 16S rRNA gene fingerprints (DGGE). Closest matches (GenBank accession numbers) from blast analysis: 1. Symbiotic algal DNA, 2.Endozoicomonas sp. (DQ200474), 3.Firmicutes sp. (HQ444233), 4.Aeromonas sp. (HQ180147), 5.Arcobacter sp. (HQ317346), 6.Vibrio harveyi (GQ203118), 7.Glycomyces sp. (JF729475), 8.Clostridium sp. (GU227558), 9.Cyanobacterium sp. (FJ844162), and (B) ciliate 18S rRNA gene fingerprint; 10.Diophrys sp. (DQ35385), 11.Pseudocarnopsis sp. (HQ228545), 12.Aspidisca sp. (AF305625), 13. Morph1 (FJ648350), 14. Morph2 (AY876050), 15.Euplotes sp. (GU953668), 16.Glauconema sp. (GQ214552), 17.Varistrombidium sp. (DQ811090), 18.Euplotes sp. (AY361908), 19.Hartmanula sp. (AY378113), 20.Holosticha sp. (DQ059583). Composite DGGE image standardized for gel-to-gel comparison using BioNumerics.