Tropical mangroves are coastal habitats with harsh environmental conditions predominantly due to tidal cycles that determine sharp gradients of salinity, oxygen and nutrient availability and of toxic compounds like plant-produced tannins and polyphenols and biogenic sulfide. The sediments are deeply perturbed by crabs that contribute to shape the carrying capacity the system. To exploit the sediments and the aerial plant root system several crab species evolved a capability to breathe in air and water allowing the exploitation of a larger niche range. Such a capacity determined a major functional evolution of the gills toward a lung-based function supporting a bimodal breathing and the catabolite excretion. We hypothesize that bacterial symbiosis is a major force shaping such a unique adaptation of the crab gills to cope with the mangrove ecosystem challenges. We focused on two mangrove key stone crab species, the ocypodid Uca urvillei and the sesarmid Perisesarma guttatum. Crabs were sampled in a large latitudinal range at their southernmost, northernmost and equatorial distribution sites respectively in the South African and Kenyan Indian Ocean coasts and the Red Sea Saudi Arabian coast. PCR-denaturing gradient gel electrophoresis, Illumina sequencing and optical, fluorescence in-situ hybridization and electron microscopy techniques, detected the constant presence along the latitudinal transect of a core bacterial community specific of each of the two species. The two communities were dominated by uncultured actinobacteria related to the genus Ilumatobacter at all the latitudes, while the other relevant group of the Rhodobacteriacee was represented by different OTUs in the three latitudes. These bacteria showed a specific location on the gill surfaces with a uniform colonization pattern in between the regularly spaced lamellae. The possible function of these bacteria is discussed in the light of their taxonomic identity and the localization on the gill surfaces.
|Titolo:||Bacterial symbiosis in dual-breathing animals living in mangrove ecosystem|
BORIN, SARA (Penultimo)
DAFFONCHIO, DANIELE GIUSEPPE (Ultimo)
|Data di pubblicazione:||giu-2015|
|Settore Scientifico Disciplinare:||Settore AGR/16 - Microbiologia Agraria|
|Citazione:||Bacterial symbiosis in dual-breathing animals living in mangrove ecosystem / M. Fusi, R. Marasco, E. Crotti, F. Mapelli, J.M. Booth, M. Cardinale, S. Borin, D. Daffonchio. ((Intervento presentato al convegno BAGECO 13 tenutosi a Milano nel 2015.|
|Appare nelle tipologie:||14 - Intervento a convegno non pubblicato|