Actinobacterial Diversity in Volcanic Caves and Associated Geomicrobiological Interactions

16 páginas.-- 8 figuras.-- 2 tablas.-- 66 referencias.-- Material suplementario http://dx.doi.org/10.3389/fmicb.2015.01342Volcanic caves are filled with colorful microbial mats on the walls and ceilings. These volcanic caves are found worldwide, and studies are finding vast bacteria diversity within these caves. One group of bacteria that can be abundant in volcanic caves, as well as other caves, is Actinobacteria. As Actinobacteria are valued for their ability to produce a variety of secondary metabolites, rare and novel Actinobacteria are being sought in underexplored environments. The abundance of novel Actinobacteria in volcanic caves makes this environment an excellent location to study these bacteria. Scanning electron microscopy (SEM) from several volcanic caves worldwide revealed diversity in the morphologies present. Spores, coccoid, and filamentous cells, many with hair-like or knobby extensions, were some of the microbial structures observed within the microbial mat samples. In addition, the SEM study pointed out that these features figure prominently in both constructive and destructive mineral processes. To further investigate this diversity, we conducted both Sanger sequencing and 454 pyrosequencing of the Actinobacteria in volcanic caves from four locations, two islands in the Azores, Portugal, and Hawai'i and New Mexico, USA. This comparison represents one of the largest sequencing efforts of Actinobacteria in volcanic caves to date. The diversity was shown to be dominated by Actinomycetales, but also included several newly described orders, such as Euzebyales, and Gaiellales. Sixty-two percent of the clones from the four locations shared less than 97% similarity to known sequences, and nearly 71% of the clones were singletons, supporting the commonly held belief that volcanic caves are an untapped resource for novel and rare Actinobacteria. The amplicon libraries depicted a wider view of the microbial diversity in Azorean volcanic caves revealing three additional orders, Rubrobacterales, Solirubrobacterales, and Coriobacteriales. Studies of microbial ecology in volcanic caves are still very limited. To rectify this deficiency, the results from our study help fill in the gaps in our knowledge of actinobacterial diversity and their potential roles in the volcanic cave ecosystems.The authors acknowledge the Spanish Ministry of Economy and Competitiveness (project CGL2013-41674-P) and FEDER Funds for financial support. AM acknowledges the support from the Marie Curie Intra-European Fellowship of the European Commission's 7th Framework Programme (PIEF-GA-2012-328689). CR was funded by the Regional Fund for Science and Technology and Pro-Emprego program of the Regional Government of the Azores, Portugal [M3.1.7/F/013/2011, M3.1.7/F/030/2011]. Her work was partly supported by National funds from the Foundation for Science and Technology of the Portuguese Government, [Understanding Underground Biodiversity: Studies in Azorean Lava Tubes (reference PTDC/AMB/70801/2006]. The authors would like to thank the TRU Innovation in Research Grant, TRU UREAP Fund, Western Economic Diversification Canada Fund, Kent Watson (assisted with the Helmcken Falls Cave sample collection), Derrick Horne (UBC BioImaging Facility for the SEM work). We acknowledged the Canadian Ministry of Forests, Lands, and Natural Resource Operations for Park Use Permit#102172. This work was also supported by the Cave Conservancy of the Virginias, the Graduate Research Allocation Committee at UNM Biology, UNM Biology Grove Scholarship, the Student Research Allocation Committee at UNM, the National Speleological Society, the New Mexico Space Grant Consortium, the New Mexico Alliance for Minority Participation Program, the New Mexico Geological Society, and Kenneth Ingham Consulting. We acknowledge support from the UNM Molecular Biology Facility, which is supported by NIH grant number P20GM103452. The authors also wish to thank Fernando Pereira, Ana Rita Varela, Pedro Correia, Berta Borges, and Guida Pires for help during field and lab work in the Azores. The authors gratefully acknowledge the photographic contributions of Kenneth Ingham and Pedro Cardoso and Michael Spilde (SEM images). The authors would like to thank Dr. Steven Van Wagoner (TRU) and Drs. Julian Davies and Vivian Miao (UBC) for their invaluable comments in manuscript preparation. We gratefully acknowledge the help and collecting permits granted by the staff of El Malpais National Monument and Hawai'i Volcanoes National Park (USA).Peer reviewe

Physicochemical, biochemical, microbiological and safety aspects of Pico cheese: assessment throughout maturation and on the final product

Pico cheese is a traditional variety manufactured on the eponymous Azorean Island (Portugal). In total, 153 cheeses were analysed. The average total solids (TS) content by the end of maturation was 63.3 +- 0.3 g/100 g, Aw 0.943-0.966, salt-in-moisture 2.12-4.17 g/100 g and pH 4.89-5.11 +-0.02. Proteolysis was similar to that of other Iberian raw milk cheeses, but the free fatty acid content was generally higher. Lactococci were the predominant bacteria. Coagulase-positive staphylococci constituted the most severe hygiene problem. Positive correlations were found between maturation time and TS, titratable acidity, Aw, proteolysis indices and Enterobacteriaceae and coagulase-positive staphylococcus viable numbers

Cavidades vulcanicas e ecossistemas subterraneos dos Acores: patrimonio natural a proteger

Artículo en Revista de DivulgaciónArtículo donde se incluyen posters y comentarios de una exposición sobre algunas grutas volcánicas de la Isla de Terceira (Azores, Portugal)N

Biotechnological potential of Actinobacteria from Canadian and Azorean volcanic caves

Caves are regarded as extreme habitats with appropriate conditions for the development of Actinobacteria. In comparison with other habitats, caves have not yet been the target of intensive screening for bioactive secondary metabolites produced by actinomycetes. As a primary screening strategy, we conducted a metagenomic analysis of the diversity and richness of a key gene required for non-ribosomal peptide (NRP) biosynthesis, focusing on cave-derived sediments from two Canadian caves (a lava tube and a limestone cave) to help us predict whether different types of caves may harbor drug-producing actinobacteria. Using degenerate PCR primers targeting adenylation domains (AD), a conserved domain in the core gene in NRP biosynthesis, a number of amplicons were obtained that mapped back to biomedically relevant NRP gene cluster families. This result guided our culture-dependent sampling strategy of actinomycete isolation from the volcanic caves of Canada (British Columbia) and Portugal (Azores) and subsequent characterization of their antibacterial and enzymatic activities. Multiple enzymatic and antimicrobial activities were identified from bacterial of the Arthrobacter and Streptomyces genera demonstrating that actinomycetes from volcanic caves are promising sources of antibacterial, antibiofilm compounds and industrially relevant enzymes. 15 páginas.-- 4 figuras.-- 3 tablas.-- referencias.-- The online version of this article (doi:10.1007/s00253-016-7932-7) contains supplementary material, which is available to authorized users.C. Riquelme was funded by the Regional Fund for Science and Technology and Pro-Emprego program of the Regional Government of the Azores, Portugal [M3.1.7/F/013/2011, M3.1.7/F/030/2011]. Her work was partly supported by National funds from the Foundation for Science and Technology of the Portuguese Government [Understanding Underground Biodiversity: Studies in Azorean Lava Tubes (reference TDC/AMB/70801/2006)]. A.Z. Miller acknowledges the support from the Marie Curie Intra-European Fellowship of the European Commission’s 7th Framework Programme (PIEF-GA-2012-328689). The authors would like to thank the TRU Innovation in Research Grant, TRU Undergraduate Research Enhancement (UREAP) Fund, Western Economic Diversification Canada Fund, Kent Watson (assisted with the Helmcken Falls Cave sample collection), Dr. Mario Jacques (U of Montreal for his assistance in biofilm culture), icholaus Vieira, Christian Stenner, and the Raspberry Rising Expedition team.We acknowledged the Canadian Ministry of Forests, Lands, and Natural Resource Operations for Park Use Permit#102172. The work done in the Brady lab was funded by NIH grant GM077516. Z. Charlop-Powers was also supported by NIH grant AI110029. The authors also wish to thank Fernando Pereira, Ana Rita Varela, Pedro Correia, Berta Borges, and Guida Pires for help during field and lab work in the Azores. The authors would like to thank Dr. Steven VanWagoner (TRU) and Drs. Julian Davies and Vivian Miao (UBC) for their invaluable comments in manuscript preparation. 15 páginas.-- figuras.-- Electronic supplementary material The online version of this article (doi:10.1007/s00253-016-7932-7) contains supplementary material, which is available to authorized users.Peer Reviewe

Volcanic Caves: Priorities for Conserving the Azorean Endemic Troglobiont Species

Azorean lava-tubes and volcanic pits adequately sampled for arthropod fauna were evaluated for species diversity and rarity. An iterative partial multiple regression analysis was performed to produce a multi-criteria index (Importance Value for Cave Conservation, IV-CC) incorporating arthropod species diversity indices but also including indices qualifying cave geological and management features (e.g., the diversity of geological structures, threats, accessibility). Additionally, we calculated complementarity solutions (irreplaceability and Fraction-of-Spare measures) for each cave with different targets per species, i.e., the minimum number of caves needed for each species to be represented either once or twice. Our results clearly show that to preserve all troglobiont arthropods endemic to the Azores, it is crucial to protect several caves per island. As many as 10 and 15 caves are needed to include one or two occurrences, respectively, per species

Silagem de resíduos da filetagem de tilápia do nilo (Oreochromis niloticus), com ácido fórmico - análise Bromatológica, físico-química e microbiológica Silage of tilapia (Oreochromis niloticus) filetage residues with formic acid Bromatological, phisico-chemical and microbiological analyses

O experimento avaliou o valor nutritivo da silagem ácida da filetagem da tilápia do Nilo (Oreochromis niloticus Linneaus, 1758), visando sua utilização em substituição à farinha de peixe na alimentação de organismo aquático. A silagem consistiu de resíduos da filetagem de tilápia (carcaça) e 3% de ácido fórmico, armazenada em temperatura ambiente (máxima média de 21,5ºC) e temperatura mínima média de 15ºC, por trinta dias, em baldes de polietileno com um orifício, por onde os gases saiam. O pH foi monitorado no 1º, 15º e 30º dia. Foram realizadas análises microbiológicas para contagem total de microrganismos e coliformes a 35ºC e 45ºC. O pH apresentou média de 3,95 ao final dos 30 dias. Nas análises microbiológicas observou-se a ausência de coliformes a 45ºC e, que a quantidade de microrganismos diminuiu gradativamente. Do ponto de vista microbiológico, a silagem ácida de resíduo da filetagem de tilápia mostrou-se como alimento alternativo viável para a alimentação animal.<br>The experiment was carried out for evaluate the nutritional value of the silage of Nile tilapia (Oreochromis niloticus Linneaus, 1758) filetage residues with formic acid as a replace of fish meal in aquatic organisms feeding as protein source. The silage consisted of tilapia filetage residues (carcass) and 3% formic acid, and it was stored in environmental temperature with a maximum average of 21,5º C and a minimum average of 15 º C, during thirty days, in polyethylene pails with an orifice for the exhaustion of gases. The pH was monitored on the 1st, 15th and 30th day. The microbiological analyses were made for the total count of microorganisms and coliforms at 35º C and 45º C. The average pH was 3.95 at the end of 30 days. The microbiological analyses showed absence of coliformes at 45º C and a gradual reduction in the quantity of microorganisms. From the microbiological standpoint, the acid silage of tilapia residues was shown to be an alternative viable diet for animal feeding