A single cyanobacterial ribotype is associated with both red and black bands on diseased corals from Palau

Abstract

Filamentous cyanobacteria forming red and black bands (black band disease, BBD) on 3 scleractinian corals from Palau were molecularly identified as belonging to a single ribotype. Red cyanobacterial mats sampled from infections on Pachyseris speciosa and a massive Porites sp. yielded red strains RMS1 and RMS2 respectively; the black cyanobacterial mat sampled from an infection on Montipora sp. yielded black strain BMS1. Following trials of a range of specialized media and culture conditions, 2 media, Grund and ASN-III, were identified as the best for successful isolation and culturing. Cultured cyanobacteria were examined under a light microscope to establish purity, color and morphological appearance. DNA extraction and partial sequencing of the 16S rDNA gene of both red and black cyanobacterial isolates demonstrated 100% sequence identity. These isolated strains were also found to have 99% sequence identity with an uncultured cyanobacterial strain previously identified by molecular techniques as belonging to a cyanobacterial ribotype associated with BBDinfected corals in the Caribbean. This is the first report of the successful isolation and culture of cyanobacterial strains derived from both red bands and BBD. Based on these findings, it is suggested that the classification of these 2 syndromes as separate coral diseases be postponed until further evidence is collected.

Changes in the bacterial community associated with black band disease in a Red Sea coral, Favia sp., in relation to disease phases

“…BBD alone. The high genetic resemblance (97 to 100%) to BBD-originating clones and isolates from different species from distant geographic areas, including Palau, the Indo-Pacific (AY839641, Sussman et al 2006), GBR, Australia (GQ204970, Sato et al 2009), and the Caribbean Sea, including St. Croix and Barbados (AF473936, Cooney et al 2002, Sekar et al 2009) and Curaçao, Netherlands Antilles (AY038527, Frias-Lopez et al 2002) may indicate that this cyanobacterial genus is a primary and important constituent of BBD over large geographic ranges. Indeed the results of the meta-analysis of clone libraries clearly indicate the presence of a dominant cyanobacterial OTU highly homologous (99%) to cyanobacterium BgP10_ 4S T strain (Pseudo scillatoria coralii; FJ210722) in BBD from 9 out of 10 geographic locations, and in 12 of the 16 coral host species sampled.…”

Microbiome shifts and the inhibition of quorum sensing by Black Band Disease cyanobacteria

“…Black Band Disease (BBD) is the first reported coral disease and the most widely distributed polymicrobial disease of corals, affecting at least 40 species worldwide (Edmunds, 1991;Littler and Littler, 1996;Sussman et al, 2006;Montano et al, 2013). The disease is recognized by the appearance of a dense, very dark-purple (black) mat that is the visible accumulation of filamentous cyanobacteria.…”

Molecular Detection and Ecological Significance of the Cyanobacterial Genera Geitlerinema and Leptolyngbya in Black Band Disease of Corals

“…The band migrates across coral colonies at rates averaging 3 mm per day and can kill entire colonies in a matter of months (3,4,46). BBD comprises a complex microbial consortium dominated by phycoerythrin-rich, gliding, filamentous cyanobacteria (2,39,41,46,50) whose identity has been the subject of recent controversy (12,14,15,47,48). It also contains populations of sulfide-oxidizing bacteria proposed to belong to the genus Beggiatoa (20,30), a group of sulfate-reducing bacteria that includes members of the genus Desulfovibrio (20,52), more than 60 species of heterotrophic bacteria (12,14,16,47), and marine fungi (36).…”