Widespread Oceanospirillaceae Bacteria in Porites spp.

Abstract

We present evidence that a clade of bacteria in the Oceanospirillaceae is widely distributed in Porites spp. and other hermatypic corals. Bacteria 16S rDNA clone libraries were prepared from community genomic DNA extracted from Porites compressa and Porites lobata surface mucus and adjacent seawater collected along a line transect off Maui. Phylogenetic affiliations of operational taxonomic units (OTUs) defined at the 97% level of nucleotide identity varied within and between the respective Porites spp. along the transect and differed from those in the seawater. One OTU (C7-A01), however, occurred in all mucus samples from both Porites species. C7-A01c affiliates with a clade of uncultivated Oceanospirillum -like bacteria; the nearest neighbors of this OTU have been reported only in the surface mucus layer of Porites spp. and other stony corals, in reef-dwelling invertebrates, and the corallivorous six-banded angelfish, Pomacanthus sexstriatus .