SignificanceWe sequenced the genome and transcriptomes of the wild olive (oleaster). More than 50,000 genes were predicted, and evidence was found for two relatively recent whole-genome duplication events, dated at about 28 and 59 million years ago. Whole genome sequencing, as well as gene expression studies, provide further insights into the evolution of oil biosynthesis, and will aid future studies aimed at further increasing the production of olive oil, which is a key ingredient of the healthy Mediterranean diet and has been granted a qualified health claim by FDA. 5 AbstractHere, we present the genome sequence and annotation of the wild olive tree (Olea europaea var. sylvestris), called oleaster, which is considered an ancestor of cultivated olive trees. More than 50,000 protein-coding genes were predicted, a majority of which could be anchored to 23 pseudo-chromosomes obtained through a newly constructed genetic map. The oleaster genome contains signatures of two Oleaceae-lineage specific paleopolyploidy events, dated at approximately 28 and 59 million years ago. These events contributed to the expansion and neofunctionalization of genes and gene families that play important roles in oil biosynthesis.The functional divergence of oil biosynthesis pathway genes, such as FAD2, SACPD, EAR and ACPTE, following duplication, has been responsible for the differential accumulation of oleic and linoleic acids produced in olive compared to sesame, a closely related oil crop. Duplicated oleaster FAD2 genes are regulated by a short-interfering RNA (siRNA) derived from a transposable element-rich region, leading to suppressed levels of FAD2 gene expression.Additionally, neofunctionalization of members of the SACPD gene family has led to increased expression of SACPD2, 3, 5 and 7, consequently resulting in an increased desaturation of steric acid. Taken together, decreased FAD2 expression and increased SACPD expression likely explain the accumulation of exceptionally high levels of oleic acid in olive. The oleaster genome thus provides important insights into the evolution of oil biosynthesis and will be a valuable resource for oil crop genomics. 6 /bodyAs a symbol of peace, fertility, health and longevity, the olive tree (Olea europaea L.) is a socio-economically important oil crop that is widely grown in the Mediterranean Basin.Belonging to the Oleaceae family (order Lamiales), it can biosynthesize essential unsaturated fatty acids and other important secondary metabolites, such as vitamins and phenolic compounds (1). The olive tree is a diploid (2n = 46) allogamous crop that can be vegetatively propagated and live for thousands of years (2). Paleobotanical evidence suggests that olive oil was already produced in the Bronze Age (3). It has been thought that cultivated varieties were derived from the wild olive tree, called oleaster (O. europaea var. sylvestris), in Asia Minor, which then spread to Greece (4). Nevertheless, the exact domestication history of the olive tree is unknown (5). Due to their longevity, oleaster...

The objective of this study was to analyze multifunctional autoprocessing repeats-in-toxin (MARTX) toxin domain organization within the aquatic species Vibrio vulnificus as well as to study the evolution of the rtxA1 gene. The species is subdivided into three biotypes that differ in host range and geographical distribution. We have found three different types (I, II, and III) of V. Vibrio vulnificus is an "accidental" pathogen, inhabiting brackish water ecosystems in temperate and tropical regions (22). The species has been subdivided into three biotypes on the basis of genetic, phenotypic, and host range differences (4, 35). Biotypes 1 and 2 are distributed worldwide while biotype 3 is geographically restricted to Israel (1,4,11,35). Three O serovars have been described in biotype 2 (serovar A, serovar E, and serovar I), and one has been identified in biotype 3 (serovar O) while biotype 1 has not been fully serotyped (2,5,11).The three biotypes of V. vulnificus can cause disease in humans after ingestion of contaminated seafood or immersion of an open wound in brackish waters (22). In healthy people, the ingestion of V. vulnificus leads to vomiting and diarrhea while external exposure produces wound infection or severe ulcerations; however, in immunocompromised people, particularly those with chronic liver disease, the pathogen can invade the bloodstream and cause septicemia, leading to death in almost 50% of the cases (22). Interestingly, biotype 2 can also infect fish (mainly eels) and shrimps and cause death by hemorrhagic septicemia, a disease called warm-water vibriosis (35). Human isolates of biotype 2 belong to the most virulent fish serovar, serovar E (1).Several studies have been performed with biotype 1 isolates to elucidate the genetic basis of V. vulnificus virulence for humans. These isolates produce a wide range of putative virulence factors, among which is a repeats-in-toxin (RTX) toxin, which belongs to the subfamily of multifunctional autoprocessing RTX (V. vulnificus MARTX [MARTX Vv ]toxin, or RtxA1) toxins. rtxA1 mutants are less virulent for mice and have lower cytotoxicity for different cell lines (17). The rtxA1 gene is practically identical in the two sequenced isolates of biotype 1 (7, 15) (98.9% and 99.5% nucleotide and amino acid identity, respectively) and codes for a protein of 5,206 amino acids (aa), which shows extensive regions of similarity with the MARTX toxin of Vibrio cholerae (MARTX Vc toxin), the most extensively studied MARTX toxin to date (28). Both toxins share the N-and C-terminal repetitive regions, which seem to be common to all MARTX toxins, a Rho-GTPase inactivation domain (RID), an autocatalytic cysteine protease domain (CPD), and an ␣/␤-hydrolase domain. Meanwhile, they differ in that the biotype 1 MARTX Vv (MARTX Vvbt1 ) toxin lacks an actin cross-linking domain (ACD) and presents three additional putative domains, DUF3 (domain of unknown function), Mcf (a domain similar to an Mcf toxin of Photorhabdus luminescens), and PMT C1/C2 (a domain similar to a portion of ...

Vibrio vulnificus (Vv) is a multi-host pathogenic species currently subdivided into three biotypes (Bts). The three Bts are human-pathogens, but only Bt2 is also a fish-pathogen, an ability that is conferred by a transferable virulence-plasmid (pVvbt2). Here we present a phylogenomic analysis from the core genome of 80 Vv strains belonging to the three Bts recovered from a wide range of geographical and ecological sources. We have identified five well-supported phylogenetic groups or lineages (L). L1 comprises a mixture of clinical and environmental Bt1 strains, most of them involved in human clinical cases related to raw seafood ingestion. L2 is formed by a mixture of Bt1 and Bt2 strains from various sources, including diseased fish, and is related to the aquaculture industry. L3 is also linked to the aquaculture industry and includes Bt3 strains exclusively, mostly related to wound infections or secondary septicemia after farmed-fish handling. Lastly, L4 and L5 include a few strains of Bt1 associated with specific geographical areas. The phylogenetic trees for ChrI and II are not congruent to one another, which suggests that inter- and/or intra-chromosomal rearrangements have been produced along Vv evolution. Further, the phylogenetic trees for each chromosome and the virulence plasmid were also not congruent, which also suggests that pVvbt2 has been acquired independently by different clones, probably in fish farms. From all these clones, the one with zoonotic capabilities (Bt2-Serovar E) has successfully spread worldwide. Based on these results, we propose a new updated classification of the species based on phylogenetic lineages rather than on Bts, as well as the inclusion of all Bt2 strains in a pathovar with the particular ability to cause fish vibriosis, for which we suggest the name “piscis.”

Intestinal microbiota is key for many host functions, such as digestion, nutrient metabolism, disease resistance, and immune function. With the growth of the aquaculture industry, there has been a growing interest in the manipulation of fish gut microbiota to improve welfare and nutrition. Intestinal microbiota varies with many factors, including host species, genetics, developmental stage, diet, environment, and sex. The aim of this study was to compare the intestinal microbiota of adult gilthead sea bream (Sparus aurata) from three groups of age and sex (1-year-old males and 2- and 4-year-old females) maintained under the same conditions and fed exactly the same diet. Microbiota diversity and richness did not differ among groups. However, bacterial composition did, highlighting the presence of Photobacterium and Vibrio starting at 2 years of age (females) and a higher presence of Staphylococcus and Corynebacterium in 1-year-old males. The core microbiota was defined by 14 Operational Taxonomic Units (OTUs) and the groups that showed more OTUs in common were 2- and 4-year-old females. Discriminant analyses showed a clear separation by sex and age, with bacteria belonging to the phyla Firmicutes, Proteobacteria and Actinobacteria driving the separation. Pathway analysis performed with the inferred metagenome showed significant differences between 1-year-old males and 4-year-old females, with an increase in infection-related pathways, nitrotoluene degradation and sphingolipid metabolism, and a significant decrease in carbohydrate metabolism pathways with age. These results show, for the first time, how intestinal microbiota is modulated in adult gilthead sea bream and highlight the importance of reporting age and sex variables in these type of studies in fish.

Abstract-The role of cyclooxygenase-2 (COX-2) in the prolonged regulation of renal function was evaluated during changes in sodium intake and reduction of NO synthesis. It was evaluated in conscious dogs by administering a selective inhibitor (nimesulide) during 8 consecutive days. Nimesulide administration to dogs with normal or high sodium load did not modify glomerular filtration rate but reduced renal blood flow (16%; PϽ0.05). The vasoconstriction elicited by COX-2 inhibition was greater when NO production was inhibited because glomerular filtration rate decreased by Ͼ25% when nimesulide was administered to dogs with a reduced NO synthesis. During low sodium intake, COX-2 inhibition elicited a decrease (PϽ0.05) of both glomerular filtration rate (34%) and renal blood flow (31%). Sodium excretion only decreased (PϽ0.05) during the first day of COX-2 inhibition in dogs with normal or high sodium load. The increase in plasma potassium levels elicited by COX-2 inhibition was greater in dogs with low sodium intake and was enhanced when NO production was inhibited. This change in potassium was not secondary to a decrease in plasma aldosterone levels. The results of this study suggest that COX-2-derived metabolites (1) play a more important role in the long-term regulation of renal hemodynamic when sodium intake is low, (2) protect the renal vasculature from the vasoconstriction secondary to a reduction in NO, (3) are only acutely involved in regulating urinary sodium excretion, and (4) Key Words: cyclooxygenase Ⅲ nitric oxide Ⅲ renal blood flow Ⅲ hemodynamics Ⅲ sodium Ⅲ prostaglandins Ⅲ renin Ⅲ aldosterone N umerous studies have demonstrated that cyclooxygenase-2 (COX-2) expression in the renal cortex increases in response to low-salt diet, and decreases when sodium intake is elevated. 1-4 These variations in COX-2 expression suggest that COX-2-derived metabolites play a major role in the control of renal hemodynamic when sodium intake is low, and probably a minor role in regulating renal hemodynamic when sodium intake is high. However, the role of COX-2 in the prolonged regulation of renal blood flow (RBF) and glomerular filtration rate (GFR) during changes in sodium intake is not well defined. [5][6][7][8] In the renal medulla, COX-2 expression increases in response to a high sodium intake. 3,4 Considering the role of prostaglandins (PGs) in the control of sodium excretion, 9 it may be proposed that COX-2 is more involved in regulating renal excretory function during high sodium intake than during normal sodium intake, but so far, it has not been evaluated whether this hypothesis is correct. The first objective of the present study was to evaluate the role of COX-2-derived metabolites in the prolonged regulation of renal hemodynamic and excretory function when sodium load is elevated or low.The role of COX-derived PG in the regulation of plasma potassium (pK) and plasma aldosterone concentration (PAC) has been demonstrated in studies showing that pK and PAC are modified during the prolonged administration of...

Vibrio vulnificus is a heterogeneous species that comprises strains virulent and avirulent for humans and fish, and it is grouped into three biotypes. In this report, we describe a PCR-based methodology that allows both the species identification and discrimination of those isolates that could be considered dangerous to public health. Discrimination is based on the amplification of a variable region located within the gene pilF, which seems to be associated with potential human pathogenicity, regardless of the biotype of the strain.

SummaryVibrio vulnificus is a marine bacterium associated with human and fish (mainly farmed eels) diseases globally known as vibriosis. The ability to infect and overcome eel innate immunity relies on a virulence plasmid (pVvbt2) specific for biotype 2 (Bt2) strains. In the present study, we demonstrated that pVvbt2 encodes a host-specific iron acquisition system that depends on an outer membrane receptor for eel transferrin called Vep20. The inactivation of vep20 did not affect either bacterial growth in human plasma or virulence for mice, while bacterial growth in eel blood/ plasma was abolished and virulence for eels was significantly impaired. Furthermore, vep20 is an ironregulated gene overexpressed in eel blood during artificially induced vibriosis both in vitro and in vivo. Interestingly, homologues to vep20 were identified in the transferable plasmids of two fish pathogen species of broad-host range, Vibrio harveyi (pVh1) and Photobacterium damselae subsp. damselae (pPHDD1). These data suggest that Vep20 belongs to a new family of plasmid-encoded fish-specific transferrin receptors, and the acquisition of these plasmids through horizontal gene transfer is likely positively selected in the fish-farming environment. Moreover, we propose Ftbp (fish transferrin binding proteins) as a formal name for this family of proteins.

Viral M-dsRNAs encoding yeast killer toxins share similar genomic organization, but no overall sequence identity. The dsRNA full-length sequences of several known M-viruses either have yet to be completed, or they were shorter than estimated by agarose gel electrophoresis. High-throughput sequencing was used to analyze some M-dsRNAs previously sequenced by traditional techniques, and new dsRNAs from atypical killer strains of Saccharomyces cerevisiae and Torulaspora delbrueckii. All dsRNAs expected to be present in a given yeast strain were reliably detected and sequenced, and the previously-known sequences were confirmed. The few discrepancies between viral variants were mostly located around the central poly(A) region. A continuous sequence of the ScV-M2 genome was obtained for the first time. M1 virus was found for the first time in wine yeasts, coexisting with Mbarr-1 virus in T. delbrueckii. Extra 5′- and 3′-sequences were found in all M-genomes. The presence of repeated short sequences in the non-coding 3′-region of most M-genomes indicates that they have a common phylogenetic origin. High identity between amino acid sequences of killer toxins and some unclassified proteins of yeast, bacteria, and wine grapes suggests that killer viruses recruited some sequences from the genome of these organisms, or vice versa, during evolution.