The expression of virulence factors in vibrio anguillarum is dually regulated by iron levels and temperature

Vibrio anguillarumcauses a hemorrhagic septicemia that affects cold- and warm-wateradapted fish species. The main goal of this work was to determine the temperature-dependent changes in the virulence factors that could explain the virulence propertiesofV. anguillarumfor fish cultivated at different temperatures. We have found thatalthough the optimal growth temperature is around 25◦C, the degree of virulence ofV. anguillarumRV22 is higher at 15◦C. To explain this result, an RNA-Seq analysiswas performed to compare the whole transcriptome profile ofV. anguillarumRV22cultured under low-iron availability at either 25 or 15◦C, which would mimic theconditions thatV. anguillarumfinds during colonization of fish cultivated at warm- orcold-water temperatures. The comparative analysis of transcriptomes at high- andlow-iron conditions showed profound metabolic adaptations to grow under low iron.These changes were characterized by a down-regulation of the energetic metabolismand the induction of virulence-related factors like biosynthesis of LPS, productionof hemolysins and lysozyme, membrane transport, heme uptake, or production ofsiderophores. However, the expression pattern of virulence factors under iron limitationshowed interesting differences at warm and cold temperatures. Chemotaxis, motility,as well as the T6SS1 genes are expressed at higher levels at 25◦C than at 15◦C.By contrast, hemolysin RTX pore-forming toxin, T6SS2, and the genes associatedwith exopolysaccharides synthesis were preferentially expressed at 15◦C. Notably,at this temperature, the siderophore piscibactin system was strongly up-regulated.In contrast, at 25◦C, piscibactin genes were down-regulated and the vanchrobactinsiderophore system seems to supply all the necessary iron to the cell. The resultsshowed thatV. anguillarumadjusts the expression of virulence factors responding to twoenvironmental signals, iron levels and temperature. Thus, the relative relevance of eachvirulence factor for each fish species could vary depending on the water temperature.The results give clues about the physiological adaptations that allowV. anguillarumtocause infections in different fishes and could be relevant for vaccine development againstfish vibriosisThis work was supported by grants AGL2015-63740-C2-1-R and RTI2018-093634-B-C21 (AEI/FEDER, EU) from the State Agency for Research (AEI) of Spain and cofunded by the FEDER Programme from the European Union. The support of Xunta de Galicia (Spain) with grant GRC2018/018 is also acknowledgedS

Secreted citrate serves as iron carrier for the marine pathogen photobacterium damselae subsp damselae

Photobacterium damselae subsp damselae (Pdd) is a Vibrionaceae that has a wide pathogenic potential against many marine animals and also against humans. Some strains of this bacterium acquire iron through the siderophore vibrioferrin. However, there are virulent strains that do not produce vibrioferrin, but they still give a strong positive reaction in the CAS test for siderophore production. In an in silico search on the genome sequences of this type of strains we could not find any ORF which could be related to a siderophore system. To identify genes that could encode a siderophore-mediated iron acquisition system we used a mini-Tn10 transposon random mutagenesis approach. From more than 1,400 mutants examined, we could isolate a mutant (BP53) that showed a strong CAS reaction independently of the iron levels of the medium. In this mutant the transposon was inserted into the idh gene, which encodes an isocitrate dehydrogenase that participates in the tricarboxylic acid cycle. The mutant did not show any growth impairment in rich or minimal media, but it accumulated a noticeable amount of citrate (around 7 mM) in the culture medium, irrespective of the iron levels. The parental strain accumulated citrate, but in an iron-regulated fashion, being citrate levels 5–6 times higher under iron restricted conditions. In addition, a null mutant deficient in citrate synthase showed an impairment for growth at high concentrations of iron chelators, and showed almost no reaction in the CAS test. Chemical analysis by liquid chromatography of the iron-restricted culture supernatants resulted in a CAS-positive fraction with biological activity as siderophore. HPLC purification of that fraction yielded a pure compound which was identified as citrate from its MS and NMR spectral data. Although the production of another citrate-based compound with siderophore activity cannot be ruled out, our results suggest that Pdd secretes endogenous citrate and use it for iron scavenging from the cell environmentThis work was supported by grants AGL2012-39274-C02-01/02 and AGL2015-63740-C2-1/2-R (AEI/FEDER, EU) from the State Agency for Research (AEI) of Spain, and co-funded by the FEDER Programme from the European Union. The support of Xunta de Galicia (Spain) with grant GRC-2014/007 is also acknowledgedS

Optimization of lipase production by solid-state fermentation of olive pomace: from flask to laboratory-scale packed-bed bioreactor

Lipases are versatile catalysts with many applications and can be produced by solid-state fermentation (SSF) using agro-industrial wastes. The aim of this work was to maximize the production of Aspergillus ibericus lipase under SSF of olive pomace (OP) and wheat bran (WB), evaluating the effect on lipase production of C/N ratio, lipids, phenols, content of sugars of substrates and nitrogen source addition. Moreover, the implementation of the SSF process in a packed-bed bioreactor and the improvement of lipase extraction conditions were assessed. Low C/N ratios and high content of lipids led to maximum lipase production. Optimum SSF conditions were achieved with a C/N mass ratio of 25.2 and 10.2% (w/w) lipids in substrate, by the mixture of OP:WB (1:1) and supplemented with 1.33% (w/w) (NH4)2SO4. Studies in a packed-bed bioreactor showed that the lower aeration rates tested prevented substrate dehydration, improving lipase production. In this work, the important role of Triton X-100 on lipase extraction from the fermented solid substrate has been shown. A final lipase activity of 223 ± 5 U g1 (dry basis) was obtained after 7 days of fermentation.Felisbela Oliveira acknowledges the financial support from Fundação para a Ciência e Tecnologia (FCT) of Portugal through grant SFRH/BD/87953/2012. José Manuel Salgado was supported by grant CEB/N2020–INV/01/2016 from Project ‘‘BIOTECNORTE-Underpinning Biotechnology to foster the north of Portugal bioeconomy’’ (NORTE-01-0145-FEDER-000004). Luı ´s Abrunhosa was supported by grant UMINHO/BPD/51/2015 from project UID/BIO/04469/2013 financed by FCT/MEC (OE). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER006684) and BioTecNorte operation (NORTE-01-0145-FEDER000004) funded by the European Regional Development Fund under the scope of Norte2020–Programa Operacional Regional do Norte. Noelia Pérez-Rodríguez acknowledges the financial support of FPU fellowship from the Spanish Ministry of Education, Culture and Sports. The authors thank the Spanish Ministry of Economy and Competitiveness for the financial support of this work (Project CTQ2015-71436-C2-1-R), which has partial financial support from the FEDER funds of the European Union.info:eu-repo/semantics/publishedVersio

MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal

Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio

Mammals in Portugal: a data set of terrestrial, volant, and marine mammal occurrences in Portugal

Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications

The fish pathogen Vibrio ordalii under iron deprivation produces the siderophore piscibactin

Vibrio ordaliiis the causative agent of vibriosis, mainly in salmonid fishes, and its virulencemechanisms are still not completely understood. In previous works we demonstrated thatV. ordaliipossess several iron uptake mechanisms based on heme utilization and siderophore production.The aim of the present work was to confirm the production and utilization of piscibactin as asiderophore byV. ordalii. Using genetic analysis, identification by peptide mass fingerprinting (PMF)of iron-regulated membrane proteins and chemical identification by LC-HRMS, we were able toclearly demonstrate thatV. ordaliiproduces piscibactin under iron limitation. The synthesis andtransport of this siderophore is encoded by a chromosomal gene cluster homologous to another onedescribed inV. anguillarum, which also encodes the synthesis of piscibactin. Usingβ-galactosidaseassays we were able to show that two potential promoters regulated by iron control the transcriptionof this gene cluster inV. ordalii. Moreover, biosynthetic and transport proteins corresponding topiscibactin synthesis and uptake could be identified in membrane fractions ofV. ordaliicells grownunder iron limitation. The synthesis of piscibactin was previously reported in other fish pathogenslikePhotobacterium damselaesubsp.piscicidaandV. anguillarum, which highlights the importance ofthis siderophore as a key virulence factor in Vibrionaceae bacteria infecting poikilothermic animalsThis work was supported by Grants CONICYT/FONDAP/15110027 and FONDECYT Nº 1190283 from the Comisión Nacional de Investigación Científica y Tecnológica (CONICYT, Chile), and by grants AGL2015-63740-C2-1-R and AGL2015-63740-C2-2-R from the State Agency for Research (AEI) of Spain, both co-funded by the FEDER Programme from the European Union. Grants from Xunta de Galicia (Spain) supporting work at University of Santiago de Compostela (grant GRC2018/18) and University of A Coruña (grant GRC2018/39 and CICA-INIBIC support ED431E2018/03) are also acknowledgedS

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data