ANTAGONISTIC ACTIVITY BETWEEN EPIBIOTIC BACTERIA ISOLATED FROM MARINE SPONGES OF THE COLOMBIAN CARIBBEAN AND ITS RELATIONSHIP WITH THE MACROFOULING

Abstract

Surfaces submerged in the sea are densely colonized by bacteria, and inter-specic interactions such as growth inhibition are important determinants of the development of bacterial communities, as well as of later phases of macrofouling. To determine the potential interactions among biolm bacteria from sponges we carried out in vitro growth inhibition tests between bacterial strains isolated from surfaces with various degrees of macrofouling, from the sponges Aplysina insularis (clean), Aplysina lacunosa (fouled), and from the calcareous surface of the bivalve mollusk Donax sp. The total percentage of antagonistic interactions among these strains was 64 %; strains isolated from clean surfaces inhibited the growth of strains from well-colonized surfaces in a 1:1 ratio. Strains from clean surfaces had a higher frequency of antagonistic interactions. We propose bacterial antagonistic interaction as a possible mechanism of population growth regulation and, consequently, of the development of subsequent phases of macrofouling.