First Report, Characterization and Pathogenicity of Isolated from Diseased Reared Larvae of Chilean Scallop, (Lamarck, 1819).

Two strains (VPAP36 and VPAP40) were isolated from moribund-settled larvae of the Chilean scallop during vibriosis outbreaks that occurred in two commercial scallop larvae hatcheries located in the Inglesa and Tongoy bays in Northern Chile. The strains were identified as using phenotypic characterization and whole genome sequence analysis. Both strains exhibited the phenotypic properties associated with virulence, gelatin hydrolysis and β-hemolysis, whereas only VPAP36 produced phospholipase and only VPAP40 produced caseinase.

Role of the Vibriolysin VemA Secreted by the Emergent Pathogen in the Colonization of Manila Clam Mucus.

is an emergent pathogen affecting clams, oysters and scallops produced in the most important countries for bivalve aquaculture. Studies concerning virulence factors involved in the virulence of are very scarce despite its global significance for aquaculture. Zinc-metalloproteases have been described as a major virulence factor in some spp.

Phage-host coevolution in natural populations.

Coevolution between bacteriophages (phages) and their bacterial hosts occurs through changes in resistance and counter-resistance mechanisms. To assess phage-host evolution in wild populations, we isolated 195 Vibrio crassostreae strains and 243 vibriophages during a 5-month time series from an oyster farm and combined these isolates with existing V. crassostreae and phage isolates.

Rapid evolutionary turnover of mobile genetic elements drives bacterial resistance to phages.

Although it is generally accepted that phages drive bacterial evolution, how these dynamics play out in the wild remains poorly understood. We found that susceptibility to viral killing in marine is mediated by large and highly diverse mobile genetic elements. These phage defense elements display exceedingly fast evolutionary turnover, resulting in differential phage susceptibility among clonal bacterial strains while phage receptors remain invariant.

First description outside Europe of the emergent pathogen Vibrio europaeus in shellfish aquaculture.

Vibrio europaeus is an emergent pathogen affecting the most important bivalve species reared in Spanish and French hatcheries. Using a genomic approach, we identified V. europaeus outside Europe for the first time from massive larval mortalities of scallop (Argopecten purpuratus) in Chile and from seawater near a shellfish hatchery in the US West Coast.

Highly Transferable pAQU-Related Plasmids Encoding Multidrug Resistance Are Widespread in the Human and Fish Pathogen Photobacterium damselae subsp. damselae in Aquaculture Areas in the Black Sea.

The marine bacterium Photobacterium damselae subsp. damselae is a pathogen that causes disease in diverse marine animals, and is also a serious opportunistic human pathogen that can cause fatal infections. Strains of this pathogen isolated from diseased European sea bass in aquaculture facilities in the Turkish coast of the Black Sea were found to exhibit reduced sensitivity to multiple antimicrobials.

Encapsulation of live marine bacteria for use in aquaculture facilities and process evaluation using response surface methodology.

New strategies are being proposed in marine aquaculture to use marine bacteria as alternative to antibiotics, as nutritional additive or as immune-stimulant. These approaches are particularly promising for larval and juvenile cultures. In many cases, the bacteria are released in the seawater, where they have to be at appropriate concentrations.

Isolation and Pathogenic Characterization of Associated With a Massive Larval Mortality Event in a Commercial Hatchery of Scallop in Chile.

The VPAP30 strain was isolated as the highly predominant bacteria from an episode of massive larval mortality occurring in a commercial culture of the Chilean scallop . The main aims of this study were, to characterize and identify the pathogenic strain using biochemical and molecular methods, to demonstrate its pathogenic activity on scallop larvae, to characterize its pathogenic properties and to describe the chronology of the pathology. The pathogenic strain was identified as based on its phenotypic properties, the multilocus sequence analysis (MLSA) of eight housekeeping genes (Z, A, B, B, H, A, A, and A) and different genome-to-genome comparisons.

Correction: Transient response of the Northwestern Iberian upwelling regime.

[This corrects the article DOI: 10.1371/journal.pone.

Transient response of the Northwestern Iberian upwelling regime.

The hydrography and dynamics of NW Iberian margin were explored for July 2009, based on a set of in situ and remote sensing observations. Zonal sections of standard CTD casts, towed CTD (SeaSoar), Acoustic Doppler Current Profilers (ADCP) and Lagrangian surveys were made to characterize cycles of upwelling and relaxation in this region. Two periods of northerly winds, bounded by relaxation periods, were responsible for the formation of an upwelling front extending to the shelf edge.

Independent estimates of marine population connectivity are more concordant when accounting for uncertainties in larval origins.

Marine larval dispersal is a complex biophysical process that depends on the effects of species biology and oceanography, leading to logistical difficulties in estimating connectivity among populations of marine animals with biphasic life cycles. To address this challenge, the application of multiple methodological approaches has been advocated, in order to increase confidence in estimates of population connectivity. However, studies seldom account for sources of uncertainty associated with each method, which undermines a direct comparative approach.

New Insights into Pathogenic Vibrios Affecting Bivalves in Hatcheries: Present and Future Prospects.

Hatcheries constitute nowadays the only viable solution to support the husbandry of bivalve molluscs due to the depletion and/or overexploitation of their natural beds. Hatchery activities include the broodstock conditioning and spawning, rearing larvae and spat, and the production of microalgae to feed all stages of the production cycle. However, outbreaks of disease continue to be the main bottleneck for successful larval and spat production, most of them caused by different representatives of the genus .

Mortality event involving larvae of the carpet shell clam Ruditapes decussatus in a hatchery: isolation of the pathogen Vibrio tubiashii subsp. europaeus.

Diseases caused by bacteria belonging to the genus Vibrio are a common, as yet unresolved, cause of mortality in shellfish hatcheries. In this study, we report the results of routine microbiological monitoring of larval cultures of the carpet shell clam Ruditapes decussatus in a hatchery in Galicia (NW Spain). Previous episodes of mortality with signs similar to those of vibriosis affecting other species in the installation indicated the possibility of bacterial infection and led to division of the culture at the early D-veliger larval stage.

Persistence of Antibiotic Resistant Vibrio spp. in Shellfish Hatchery Environment.

The characterization of antibiotic-resistant vibrios isolated from shellfish aquaculture is necessary to elucidate the potential transfer of resistance and to establish effective strategies against vibriosis. With this aim, we analyzed a collection of bacterial isolates obtained from 15 failed hatchery larval cultures that, for the most part, had been treated experimentally with chloramphenicol to prevent vibriosis. Isolates were obtained during a 2-year study from experimental cultures of five different clam species.

Vibrio barjaei sp. nov., a new species of the Mediterranei clade isolated in a shellfish hatchery.

Seven isolates were obtained from different culture stages of carpet shell clam (Ruditapes decussatus) reared in a bivalve hatchery (Galicia, NW Spain). Three groups were differentiated by genotyping techniques and phenotypic profiles and representative trains were selected to further taxonomic studies. These strains were studied by a polyphasic approach and in basis of the phylogenetic analysis based on concatenated sequences of the five housekeeping genes ftsZ, gyrB, pyrH, recA and rpoA formed a tight group into the Mediterranei clade of the genus Vibrio.

Reclassification of the larval pathogen for marine bivalves Vibrio tubiashii subsp. europaeus as Vibrio europaeus sp. nov.

The Orientalis clade has a relevant significance for bivalve aquaculture since it includes the pathogens Vibrio bivalvicida, Vibrio tubiashii subsp. tubiashii and Vibrio tubiashii subsp. europaeus.

Draft Genome Sequence of the Emerging Bivalve Pathogen Vibrio tubiashii subsp. europaeus.

Vibrio tubiashii subsp. europaeus is a bivalve pathogen isolated during episodes of mortality affecting larval cultures in different shellfish hatcheries. Here, we announce the draft genome sequence of the type strain PP-638 and describe potential virulence factors, which may provide insight into the mechanism of pathogenicity.

Vibrio sonorensis sp. nov. isolated from a cultured oyster Crassostrea gigas.

Strain CAIM 1076 was isolated from a cultured oyster Crassostrea gigas in Puerto Peñasco, Sonora state, México. The strain was taxonomically characterised by means of a genomic approach, comprising 16S rRNA gene sequence analysis, multilocus sequence analysis (MLSA), the DNA G+C content and whole genome analyses (ANI and GGDC), and by phenotypic characterisation. Strain CAIM 1076 was found to be catalase and oxidase positive, and cells were observed to be motile and facultative anaerobic.

Draft Genome Sequence of the New Pathogen for Bivalve Larvae Vibrio bivalvicida.

Vibrio bivalvicidais a novel pathogen of bivalve larvae responsible for recent vibriosis outbreaks affecting shellfish hatcheries. Here, we announce the draft genome sequence ofV. bivalvicida605(T)and describe potential virulence factors.

Vibrio bivalvicida sp. nov., a novel larval pathogen for bivalve molluscs reared in a hatchery.

Three isolates were obtained from cultures of carpet shell clam (Ruditapes decussatus) reared in a bivalve hatchery (Galicia, NW Spain) from different sources: healthy broodstock, moribund larvae and the seawater corresponding to the larval tank. All isolates were studied by a polyphasic approach, including a phylogenetic analysis based on concatenated sequences of the five housekeeping genes ftsZ, gyrB, pyrH, recA and rpoA. The analysis supported their inclusion in the Orientalis clade of the genus Vibrio, and they formed a tight group separated from the closest relatives: Vibrio tubiashii subsp.

Following the infection process of vibriosis in Manila clam (Ruditapes philippinarum) larvae through GFP-tagged pathogenic Vibrio species.

Vibriosis represents the main bottleneck for the larval production process in shellfish aquaculture. While the signs of this disease in bivalve larvae are well known, the infection process by pathogenic Vibrio spp. during episodes of vibriosis has not been elucidated.

Phytoplankton production systems in a shellfish hatchery: variations of the bacterial load and diversity of vibrios.

Aims: Outbreaks of disease caused by some Vibrio species represent the main production bottleneck in shellfish hatcheries. Although the phytoplankton used as food is one of the main sources of bacteria, studies of the associated bacterial populations, specifically vibrios, are scarce. The aim of the study was the microbiological monitoring of the microalgae as the first step in assessing the risk disease for bivalve cultures.

Characterization of pathogenic vibrios isolated from bivalve hatcheries in Galicia, NW Atlantic coast of Spain. Description of Vibrio tubiashii subsp. europaeus [corrected] subsp. nov.

The taxonomic position of the bivalve pathogen PP-638 was studied together with five similar isolates. The strains were isolated from flat oyster (Ostrea edulis) and Manila clam (Venerupis philippinarum) cultures during outbreaks of disease in two shellfish hatcheries (Galicia, NW Spain). The pathogenicity, previously established for PP-638, was demonstrated with all isolates and for several bivalve species, including the original hosts.

Vibrio ostreicida sp. nov., a new pathogen of bivalve larvae.

The taxonomic position of the bivalve pathogen PP-203T was studied together with those of two similar isolates (PP-200 and PP-204). The bacterial strains were isolated from samples of young oyster spat in a bivalve hatchery in Galicia (NW Spain), which was continually affected by outbreaks of disease and severe mortalities. On the basis of 16S rRNA gene sequencing, the three strains formed a cluster within the genus Vibrio and were most closely related to Vibrio pectenicida DSM 19585T (97.