Stimulated bacterioplankton growth and selection for certain bacterial taxa in the vicinity of the ctenophore Mnemiopsis leidyi

Abstract

Episodic blooms of voracious gelatinous zooplankton, such as the ctenophore Mnemiopsis leidyi, affect pools of inorganic nutrients and dissolved organic carbon by intensive grazing activities and mucus release. This will potentially influence bacterioplankton activity and community composition, at least at local scales; however, available studies on this are scarce. In the present study we examined effects of M. leidyi on bacterioplankton growth and composition in incubation experiments. Moreover, we examined community composition of bacteria associated with the surface and gut of M. leidyi. High release of ammonium and high bacterial growth was observed in the treatments with M. leidyi relative to controls. Deep 454 pyrosequencing of 16 S rRNA genes showed specific bacterial communities in treatments with M. leidyi as well as specific communities associated with M. leidyi tissue and gut. In particular, members of Flavobacteriaceae were associated with M. leidyi. Our study shows that M. leidyi influences bacterioplankton activity and community composition in the vicinity of the jellyfish. In particular during temporary aggregations of jellyfish, these local zones of high bacterial growth may contribute significantly to the spatial heterogeneity of bacterioplankton activity and community composition in the sea.

Sterile Surfaces of <i>Mnemiopsis leidyi</i> (Ctenophora) in Bacterial Suspension—A Key to Invasion Success?

“…seem to indicate that Mnemiopsis has few to no bacteria on the epidermis while the gut contains bacteria characteristic of the free-living populations (Moss, unpublished results). By contrast Daniels & Breitbart [28] found a temporally variable microbiota that, however, clearly differed from free-living communities in the surrounding water column, and Dinsquet et al [29] identified specific communities associated with M. leidyi tissue and gut. It is likely that the effects that bacterial symbionts exert on their host are mediated by environmental conditions and the resulting status of the host.…”

Microbial Surface Colonization and Biofilm Development in Marine Environments

“…Studies have shown that Bacteroidetes bacteria are common in marine environments (791), abundant in organic particle-rich coastal waters (108,113,130,611,791), responsive to algal and jellyfish blooms (272,537,756,(791)(792)(793), copiotrophic (252), and prone to leading a surface-associated life (12,17,246,272,574,607) supported by the extracellular degradation of complex biopolymers such as polysaccharides and proteins (194,791,(794)(795)(796)(797). These bacteria harbor a large number of genes for adhesive exopolysaccharides, adhesion proteins, proteases, peptidases, glycoside hydrolases, and lipases, and several genes for biopolymer degradation are coregulated with the genes for TonBdependent transport systems (794,795,(798)(799)(800)(801)(802).…”

Composition of Bacterial Communities Associated with Aurelia aurita Changes with Compartment, Life Stage, and Population

“…Depending on the variety of different niches provided by the host, which can change according to developmental stage, diet, or other environmental factors, diverse and specific microbial communities can establish themselves with hosts (3). Previous investigations demonstrated that marine invertebrates harbor bacteria as stable associates recruited from the ocean's pool of potential colonizers (4)(5)(6). A well-studied example is the symbiosis between the squid Euprymna scolopes and Vibrio fischeri, which is crucial for certain developmental steps of the squid (7,8).…”