Does a polyphagous caterpillar have the same gut microbiota when feeding on different species of food plants?

artículo -- Universidad de Costa Rica. Centro de Investigación en Biología Molecular, 2002We used classical culture techniques to explore gut bacteria and changes associated with dietary change in the highly polyphagous, tropical caterpillar Automeris zugana(Saturniidae). Fifty-five third instar wild-caught sibs feeding on Annona purpurea(Annonaceae) in the Área de Conservación Guanacaste (ACG) in northwestern Costa Rica were divided into eight groups. Each of seven groups was reared to the ultimate instar on another species of food plant normally used by A. zugana. Some pupae were also analyzed for the presence of bacteria. Aerobic bacterial cultures were obtained from all 33 caterpillar guts and the eight pupae inventoried. There was no clear pattern in species composition of cultivated bacteria among the eight diets, and each caterpillar on a given food plant carried only a small fraction of the total set of species isolated from the set of caterpillars feeding on that food plant. Taken as a whole, the larvae and pupae contained 22 species of cultivable bacteria in 12 genera. Enterobacter, present in 81.8% of the samples, was the genus most frequently isolated from the caterpillars, followed by Micrococcusand Bacillus. Bacillus thuringiensiswas isolated from 30.3% of the dissected caterpillars, but found in caterpillars feeding on only half of the species of food plants.Usamos técnicas de cultivo clásicas para explorar las bacterias del intestino y los cambios asociados con el cambio dietético en la, altamente polífaga, oruga tropical Automeris zugana (Saturniidae). Se capturaron 55 individuos hermanos, silvestres, de tercer estadio, alimentándose de Annona purpurea(Annonaceae) en el Área de Conservación Guanacaste (ACG) en el noroeste de Costa Rica y se dividieron en ocho grupos. Siete grupos fueron criados hasta el último estadio en otra especie de planta a la normalmente usada por A. zugana. Algunas pupas también fueron analizadas para ver la presencia de bacterias. Se obtuvieron cultivos de bacterias aeróbicas de los 33 intestinos de las orugas y de las ocho pupas muestreadas. No hubo un patrón claro en la composición de especies de las bacterias cultivadas entre las ocho dietas y cada oruga en una planta dada representó solo una pequeña fracción del conjunto total de especies aisladas de orugas alimentándose de esa planta. Tomándolas como un solo grupo, las larvas y pupas tuvieron 22 especies de bacterias cultivables en 12 géneros. Enterobacter, presente en 81.8% de las muestras, fue el género aislado de las orugas con más frecuencia, seguido por Micrococcusy Bacillus. Bacillus thuringiensisfue aislado de 30.3% de las orugas disectadas, pero encontrado en orugas alimentándose de solo la mitad de las especies de plantas.CONICIT, San José, Costa Rica, grant Ref 3-208-99Universidad de Costa Rica, Vicerrectoría de Investigación, grant VI 801-99-506NSF DEB 9400829, DEB 9705072 to D.H. JanzenUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM

Evidence for Widespread Associations between Neotropical Hymenopteran Insects and Actinobacteria

The evolutionary success of hymenopteran insects has been associated with complex physiological and behavioral defense mechanisms against pathogens and parasites. Among these strategies are symbiotic associations between Hymenoptera and antibiotic-producing Actinobacteria, which provide protection to insect hosts. Herein, we examine associations between culturable Actinobacteria and 29 species of tropical hymenopteran insects that span five families, including Apidae (bees), Vespidae (wasps), and Formicidae (ants). In total, 197 Actinobacteria isolates were obtained from 22 of the 29 different insect species sampled. Through 16S rRNA gene sequences of 161 isolates, we show that 91% of the symbionts correspond to members of the genus Streptomyces with less common isolates belonging to Pseudonocardia and Amycolatopsis. Electron microscopy revealed the presence of filamentous bacteria with Streptomyces morphology in brood chambers of two different species of the eusocial wasps. Four fungal strains in the family Ophiocordycipitacea (Hypocreales) known to be specialized insect parasites were also isolated. Bioassay challenges between the Actinobacteria and their possible targeted pathogenic antagonist (both obtained from the same insect at the genus or species level) provide evidence that different Actinobacteria isolates produced antifungal activity, supporting the hypothesis of a defensive association between the insects and these microbe species. Finally, phylogenetic analysis of 16S rRNA and gyrB demonstrate the presence of five Streptomyces lineages associated with a broad range of insect species. Particularly our Clade I is of much interest as it is composed of one 16S rRNA phylotype repeatedly isolated from different insect groups in our sample. This phylotype corresponds to a previously described lineage of host-associated Streptomyces. These results suggest Streptomyces Clade I is a Hymenoptera host-associated lineage spanning several new insect taxa and ranging from the American temperate to the Neotropical region. Our work thus provides important insights into the widespread distribution of Actinobacteria and hymenopteran insects associations, while also pointing at novel resources that could be targeted for the discovery of active natural products with great potential in medical and biotechnological applications.National Science Foundation/[MCB-0702025]/NSF/Estados UnidosUniversidad de Costa Rica/[801-B0-538]/UCR/Costa RicaUniversidad de Costa Rica/[810-B3-185]/UCR/Costa RicaNational Institute of Health/[U19 Al109673]/NIH/Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Estructuras Microscópicas (CIEMIC)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Enfermedades Tropicales (CIET)UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicin

Genome Sequencing of Sulfolobus sp. A20 from Costa Rica and Comparative Analyses of the Putative Pathways of Carbon, Nitrogen, and Sulfur Metabolism in Various Sulfolobus Strains

The genome of Sulfolobus sp. A20 isolated from a hot spring in Costa Rica was sequenced. This circular genome of the strain is 2,688,317 bp in size and 34.8% in G+C content, and contains 2591 open reading frames (ORFs). Strain A20 shares ~95.6% identity at the 16S rRNA gene sequence level and <30% DNA-DNA hybridization (DDH) values with the most closely related known Sulfolobus species (i.e., Sulfolobus islandicus and Sulfolobus solfataricus), suggesting that it represents a novel Sulfolobus species. Comparison of the genome of strain A20 with those of the type strains of S. solfataricus, Sulfolobus acidocaldarius, S. islandicus, and Sulfolobus tokodaii, which were isolated from geographically separated areas, identified 1801 genes conserved among all Sulfolobus species analyzed (core genes). Comparative genome analyses show that central carbon metabolism in Sulfolobus is highly conserved, and enzymes involved in the Entner-Doudoroff pathway, the tricarboxylic acid cycle and the CO2 fixation pathways are predominantly encoded by the core genes. All Sulfolobus species encode genes required for the conversion of ammonium into glutamate/glutamine. Some Sulfolobus strains have gained the ability to utilize additional nitrogen source such as nitrate (i.e., S. islandicus strain REY15A, LAL14/1, M14.25, and M16.27) or urea (i.e., S. islandicus HEV10/4, S. tokodaii strain7, and S. metallicus DSM 6482). The strategies for sulfur metabolism are most diverse and least understood. S. tokodaii encodes sulfur oxygenase/reductase (SOR), whereas both S. islandicus and S. solfataricus contain genes for sulfur reductase (SRE). However, neither SOR nor SRE genes exist in the genome of strain A20, raising the possibility that an unknown pathway for the utilization of elemental sulfur may be present in the strain. The ability of Sulfolobus to utilize nitrate or sulfur is encoded by a gene cluster flanked by IS elements or their remnants. These clusters appear to have become fixed at a specific genomic site in some strains and lost in other strains during the course of evolution. The versatility in nitrogen and sulfur metabolism may represent adaptation of Sulfolobus to thriving in different habitats.Fundación Nacional de Ciencias Naturales de China/[31130003]/NSFC/ChinaUniversidad de Costa Rica/[VI 801–B0–530]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM

First insights into the prokaryotic community structure of Lake Cote, Costa Rica: influence on nutrient cycling

This article is part of the Research Topic: Rising Stars in Aquatic Microbiology: 2022Prokaryotic diversity in lakes has been studied for many years mainly focusing on community structure and how the bacterial assemblages are driven by physicochemical conditions such as temperature, oxygen, and nutrients. However, little is known about how the composition and function of the prokaryotic community changes upon lake stratification. To elucidate this, we studied Lake Cote in Costa Rica determining prokaryotic diversity and community structure in conjunction with physicochemistry along vertical gradients during stratification and mixing periods. Of the parameters measured, ammonium, oxygen, and temperature, in that order, were the main determinants driving the variability in the prokaryotic community structure of the lake. Distinct stratification of Lake Cote occurred (March 2018) and the community diversity was compared to a period of complete mixing (March 2019). The microbial community analysis indicated that stratification significantly altered the bacterial composition in the epi-meta- and hypolimnion. During stratification, the Deltaproteobacteria, Chloroflexi, Bacteroidetes, Nitrospirae, and Euryarchaeota were dominant in the hypolimnion yet largely absent in surface layers. Among these taxa, strict or facultative anaerobic bacteria were likely contributing to the lake nitrogen biogeochemical cycling, consistent with measurements of inorganic nitrogen measurements and microbial functional abundance predictions. In general, during both sampling events, a higher abundance of Alphaproteobacteria, Betaproteobacteria, Actinobacteria, and Cyanobacteria was found in the oxygenated layers. Lake Cote had a unique bacterial diversity, with 80% of Amplicon Sequence Variant (ASV) recovered similar to unclassified/uncultured strains and exhibits archetypal shallow lake physicochemical but not microbial fluctuations worthy of further investigation. This study provides an example of lake hydrodynamics impacts to microbial community and their function in Central American lakes with implications for other shallow, upland, and oligotrophic lake systems

Análisis eledroforético de las secreciones adhesivas de onicóforos del género Epiperipatus (Onychophora: ·Peripatidae)

Los onicóforos utilizan sus secreciones adhesivas para la defensa y captura de presas. La composición proteíca de la secreción adhesiva de varias especies costarricenses de onicóforos del género Epiperipatus, fue estudiada utilizando geles discontinuos de poliacrilamida- SOS. Los resultados obtenidos de la electroforesis de extractos acuosos de esta secreción teñidos con Azul de Coomassie, revelan la presencia de un patrón peptídico complejo, con muchas bandas conservadas de alto peso molecular y unas pocas bandas específicas de bajo peso molecular. El análisis de extractos provenientes de diferentes individuos de la especie más abundante (E. biolleyi) muestra patrones idénticos, mientras que las 4 especies analizadas poseen un patrón único. Estos patrones específicos podrían ser utilizados para la identificación taxonómica en este filo. La gran variabilidad en tamaño y número de estos péptidos sugiere que podrían cumplir una función general (e.&amp; gelación a través de la formación de puentes disulfuro) y no una función catalítica específica.Onychophorans use their adhesive secretion to capture prey and for defense. The protein composition of this secretion was studied in several species of Epiperipatus from Costa Rica, using polyacrylarnide gel electrophoresis with sodium dodecyl sulphate (SDS-PAGE). A complex pattern of proteins appeared in acquous extracts of the secrelion after electrophoresis and slaining with Coomassie Brilliant Blue. Many conserved high molecular weight bands are detected, and a few low molecular weight bands that are abundant and species-specific. Extracts from many different individuals of the abundant species E. biolleyi show identical patterns, while each of the four species analized had a unique band patíern. These specific patterns of small peptides may be useful for taxonomic identification in this phylum. The large variability in size and number of these peptides suggests Ihat they play a general function such as gelation through disulfide bond formation, and not a specific catalytic functio

The genome of Epiperipatus biolleyi (Peripatidae), a Costa rican onychophoran

Cytologic studies of Epiperipatus biolleyi, a Costa Rican onychophoran, reveal the presence of a large genome (C-value=4.3 pg/C) with many chromosomes, and a bimodal karyotype. Analysis of maje meiosis indicates lha! all chromosomes are rod-shaped, without distinct primary constrictions. Two large bivalents are consistently associated with nucleoli. Meiosis proceeds through the pachytene stage, with a few thick bivalents that break up into many small and a few large chromosomes at the diplotene stage. At metaphase the rod-shaped bivalents seem to be pulled from the telomeres into opposite poles of the spindle, lacking well defined kinetochores. DNA isolated from E. biolleyi presents a complex profile with very low GC-content in isopycnic cesium gradients. Digestion with restriction enzymes produces a homogenous spread of molecules, except with Rae III, Hind m and Bgl n, which generate distinct bands of fluorescence. A Bgl n repeat of 1.9 Kb, has been cloned for evolutionary studies. Based on these results, many repetitive DNA familíes should be found in this genome.Cytologic studies of Epiperipatus biolleyi, a Costa Rican onychophoran, reveal the presence of a large genome (C-value=4.3 pg/C) with many chromosomes, and a bimodal karyotype. Analysis of maje meiosis indicates lha! all chromosomes are rod-shaped, without distinct primary constrictions. Two large bivalents are consistently associated with nucleoli. Meiosis proceeds through the pachytene stage, with a few thick bivalents that break up into many small and a few large chromosomes at the diplotene stage. At metaphase the rod-shaped bivalents seem to be pulled from the telomeres into opposite poles of the spindle, lacking well defined kinetochores. DNA isolated from E. biolleyi presents a complex profile with very low GC-content in isopycnic cesium gradients. Digestion with restriction enzymes produces a homogenous spread of molecules, except with Rae III, Hind m and Bgl n, which generate distinct bands of fluorescence. A Bgl n repeat of 1.9 Kb, has been cloned for evolutionary studies. Based on these results, many repetitive DNA familíes should be found in this genome

Draft Genome Sequences of Two Cyanobacteria Leptolyngbya spp. Isolated from Microbial Mats in Miravalles Thermal Spring, Costa Rica

We report the draft genome sequences of Leptolyngbya sp. strain 7M and Leptolyngbya sp. strain 15MV, isolated from Miravalles Thermal Spring, Costa Rica. The thermophilic cyanobacteria exhibit unique diversity features that provide insight into the adaptation and evolution of phototrophic microorganisms in geothermal habitats.Universidad de Costa Rica/[801-C0054]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Agronomí

A new species of euglena isolated from a hot and acid mud pool located in Las Pailas de Barro, Volcán Rincón de la Vieja, Costa Rica

Se describe una nueva especie de euglena aislada de las Pailas de Barro Caliente del Volcán Rincón de la Vieja, Costa Rica. Esta especie se caracteriza por habitar sitios ácidos y calientes. Euglena pailasensis sp. nov. tiene como características principales: la ausencia de flagelos, presencia de filamentos similares a “pilis”, presencia de cloroplastos con pirenoides atravesados por varios tilacoides, además, es termotolerante y acido-tolerante. Los análisis filogenéticos para el gen ADNr 18S y la secuencia del gen para la enzima Gap C indican que la nueva especie está relacionada con E. mutabilis. Las características taxonómicas basadas en la morfología, biología y secuencia del ADNr 18S y los genes GAP C, son discutidas y comparadas con otras especies relativamente cercanas al género.This species inhabits hot and acid environments. Euglena pailasensis sp. nov. main features are: the absence of flagella, the presence filaments like “pilis”, the presence of chloroplasts with pyrenoids crossed by several tylakoids, and acid and heat tolerance. Molecular phylogeny studies using 18S rDNA and Gap C genes indicated that the new species is related to E mutabilis. Its taxonomic characters based on morphology, biology and sequence of the 18S rDNA and Gap C genes are discussed and compared with other closely related species of the genus

Impact of oxytetracycline and bacterial bioaugmentation on the efficiency and microbial community structure of a pesticide-degrading biomixture

UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro en Investigación en Contaminación Ambiental (CICA

A microbial consortium from a biomixture swiftly degrades high concentrations of carbofuran in fluidized-bed reactors

An on-farm biopurification system (BPS) biomixture, with proven capacity to degrade carbofuran (CBF) was used as inoculum for a selective-enrichment process to obtain a bacterial consortium capable of using CBF as a sole source of carbon. Bacterial strains that comprise the consortium were identified as members of the genera Cupriavidus, Achromobacter and Pseudomonas. The consortium was tested in batch bioreactors, with initial CBF concentrations ranging from 50 to 200 mg L−1, in which complete degradation was attained in 16–17 h. Continuous operation of the bioreactor was optimized to achieve conditions of complete removal of up to 100 mg L−1 of CBF at a HRT of 23 h by the microbial consortium. Cross-degradation assays showed that the consortium was also capable of degrading high concentrations of other carbamates such as aldicarb, methiocarb and methomyl in batch bioreactors. The use of this consortium for the treatment of CBF and other carbamates at reactor scale represents a potential approach for the removal of these pesticides from agricultural wastewater, as an alternative to BPS.Ministerio de Ciencia, Tecnología y Telecomunicaciones/[FI-093-13]/MICITT/Costa RicaUniversidad de Costa Rica/[802-B4-503]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM