Adhesion ability to coral mucus of isolated bacteria from Pocillopora sp. and Porites panamensis of California Gulf southeast

The study of coral microbiota is of fundamental importance for a better understanding of the processes that determine its association with the holobiont, however, little is known about the basic mechanisms of this association. In this research, the objective was to isolate from corals without apparent signs of disease, the predominant bacteria of the community, determine their ability to adhere to the mucus produced by Pocillopora sp. and identify them molecularly. Corals of the genera Pocillopora sp. and Porites panamensis were recollected, the population of four groups of microorganisms (expressed as Log of CFU g-1) was quantified. Results indicated aerobic mesophilic bacteria (4.7 - 6.4), lactic acid bacteria (Ë‚1.0-5.8), bacteria of the Vibrio genus (Ë‚ 1.0-4.5), as well as fungi and yeasts (Ë‚1.0-3.6). 156 bacterial strains of the homogenized holobiont were isolated and those with the highest growth at 24 h were selected for the adhesion test, which consisted of 25 strains of Pocillopora sp. and 27 of P. panamensis. The adhesion test to the enzymatically labeled with HRP crude mucus extract of Pocillopora sp., showed that 82% of the strains adhere. DNA was extracted from all strains, however, with the universal oligonucleotides used, only 32 PCR products were obtained. 14 strains from Pocillopora sp. and 18 from P. panamensis were molecularly identified based on the sequencing and analysis of the 16S DNAr gene. The strains identified corresponded to 17 species, where the genus Bacillus predominated, with 64% in Pocillopora sp. and 44% in P. panamensis. The species of bacteria that share these corals are B. subtilis and Staphylococcus hominis. It is suggested that the identified adherent species have the ability to colonize coral mucus, are commensal and potentially beneficial, because they were isolated from apparently healthy corals.