Population dynamics of Vibrio spp. associated with marine sponge microcosms

Abstract

Vibrio is a diverse genus of marine-associated bacteria with at least 74 species and more expected as additional marine ecospheres are interrogated. This report describes a phylogenetic reconstruction of Vibrio isolates derived from one such unique ecosystem, marine sponges (Phylum Porifera) collected from depths of 150 to 1242 feet. 16S rRNA gene sequencing along with molecular typing of 16S-23S rRNA intergenic spacer regions clustered many sponge-associated Vibrio (spp) with current known species. That is, several benthic Vibrio species commensal with Porifera sponges seemed genetically linked to vibrios associated with coastal or shallow-water communities, signalling a panmictic population structure among seemingly ecologically disparate strains. Conversely, phylogenetic analysis provided evidence for at least two novel Vibrio speciation events within this specific sponge microcosm. Collectively, these findings earmark this still relatively unknown environment as a bastion of taxonomic and phylogenetic variability for the genus and probably other bacterial taxa.

Integration of Culture-Based and Molecular Analysis of a Complex Sponge-Associated Bacterial Community

“…Wilkinson et al pioneered this effort and found a similar sponge-specific bacterial isolate that was found in 9 out of 10 sponges samples from both the Mediterranean and Great Barrier Reef [39]. Several studies have noted cultured sponge-specific isolates from many marine sponges in difference locations [40], [41]. A recent survey of the largest cultured collection of bacteria associated with marine sponges uncovered sponge specific isolates that were previously reported as “uncultured” however; nearly 88% of the isolates were dominated by the commonly cultivable class Gammaproteobacteria [42].…”

Ecological determinants of the occurrence and dynamics of Vibrio parahaemolyticus in offshore areas

“…The absence of barriers for dispersal prevents the operation of selection for speciation and niche specialization (Oakley et al, 2010;Preheim et al, 2010). Together with the high rates of recombination of Vibrio (Vos and Didelot, 2009), these processes may constitute the major forces shaping the genetic diversity of the Vibrio populations found in marine microbiomes (Hoffmann et al, 2010;Preheim et al, 2010).…”

“…In the absence of dispersal barriers, resident V. parahaemolyticus would be exposed to a frequent admixture with zooplankton-associated populations. This mechanism can produce constraints on niche specialization, as recently suggested for Vibrio populations from different microbiomes (Hoffmann et al, 2010;Preheim et al, 2010).…”

“…Among these species, Vibrio parahaemolyticus inhabits natural environments with moderate salinity and warm temperature conditions, and its life cycle has consequently been associated with estuarine systems (Kaneko and Colwell, 1973, 1975, 1978Joseph et al, 1982). Moreover, V. parahaemolyticus has been regularly isolated from the microbiome of different marine organisms, such as corals (Chimetto et al, 2008), fish (Cabrera-Garcia et al, 2004;Herrera et al, 2006;Terzi et al, 2009), molluscs (Blackstone et al, 2003;Martinez-Urtaza et al, 2008b), sponges (Hoffmann et al, 2010), shrimp (Cabanillas-Beltrán et al, 2006) and zooplankton (Kaneko and Colwell, 1973;Baffone et al, 2006). The interaction with planktonic organisms has a central role in the pelagic ecology of Vibrio populations.…”

Interactions ofVibriospp. with Zooplankton

“…have been found to be associated with many higher organisms including fish (6), corals (7), sponges (8), hydroids (9), crabs (10), mollusks (11), and protozoa (12) (for a review of reservoirs for Vibrio cholerae see reference 13). Despite the majority of these associations being benign or beneficial, the majority of current research usually focuses on pathogenic Vibrio spp.…”