Estudo da diversidade de vibrios na microbiota do coral Siderastrea stellata presente em ambientes de recifes de arenito na costa de Fortaleza-Ceará.

Abstract

Coral reef communities are extremely important ecosystems in terms of biological resources, presenting great diversity and importance for the balance of marine environments. The coral species Siderastrea stellata is endemic to Brazil and is commonly found from Maranhão to Rio de Janeiro. Like other communities, this species has suffered significant losses due to the combined action of natural and anthropogenic factors, such as the appearance of diseases, which may be caused by bacteria. Bacteria of the genus Vibrio are opportunistic pathogens, prominent as causing disease in corals. High temperatures can lead to the proliferation of these bacteria, in addition to inducing virulence factors related to motility, degradation of host tissues, secretion of enzymes and resistance to antimicrobials. Therefore, the objective of the research was to verify and compare the abundance of vibrio in water samples, and the whitened and healthy coral Siderastrea stellata, in the intertidal sandstone reef located at Meireles beach, coast of Fortaleza-CE. The TCBS selective medium was used to quantify and isolate suspicious Vibrio strains, and were also subjected to the gram staining technique and genotypic identification. In general, temperature and salinity did not change in the sampled months. The density of Vibrio ssp. was significantly higher in the dry season in all samples, being more abundant in water compared to coral samples. Bleached corals showed higher Vibrios density in the rainy season and healthy corals in the dry season. The Vibrio genus was confirmed in all samples using molecular techniques, and potentially pathogenic coral species were not identified.