Biosurfactants production by marine yeasts isolated from zoanthids and characterization of an emulsifier produced by Yarrowia lipolytica LMS 24B.

The present study investigates the potential for biosurfactant production of 19 marine yeast species obtained from zoanthids. Using the emulsification index test to screen the samples produced by the marine yeasts, we verified that five isolates exhibited an emulsification index ≥50%. Additional tests were performed on such isolates, including oil displacement, drop collapse, Parafilm M assay, and surface tension measurement. The tolerance of produced biosurfactants for environmental conditions was also analyzed, especially considering the media's temperature, pH, and salinity. Moreover, the surfactant's ability to emulsify different hydrocarbon sources and to metabolize kerosene as the sole carbon source was evaluated in vitro. Our results demonstrate that yeast biosurfactants can emulsify hydrocarbon sources under different physicochemical conditions and metabolize kerosene as a carbon source. Considering the Yarrowia lipolytica LMS 24B as the yeast model for biosurfactant production from the cell's wall biomass, emulsification indexes of 61.2% were obtained, even at a high temperature of 120 °C. Furthermore, the Fourier-transform middle infrared spectroscopy (FTIR) analysis of the biosurfactant's chemical composition revealed the presence of distinct functional groups assigned to a glycoprotein complex. Considering the status of developing new bioproducts and bioprocesses nowadays, our findings bring a new perspective to biosurfactant production by marine yeasts, especially Y. lipolytica LMS 24B. In particular, the presented results validate the relevance of marine environments as valuable sources of genetic resources, i.e., yeast strains capable of metabolizing and emulsifying petroleum derivatives.

Microbiota of healthy and bleached corals of the species Siderastrea stellata in response to river influx and seasonality in Brazilian northeast.

Although coral bleaching is increasing worldwide due to warming oceans exacerbated by climate change, there has been a growing recognition that local stressors may play an additional role. Important stressors include the physicochemical and microbiological influences that are related to river runoff. Here, we investigated the microbiota associated to mucus and tissue of endemic coral Siderastrea stellata, collected from Brazilian northeast coral reefs of Barra de Santo Antônio (subject to river runoff) and Maragogi (minimal river runoff) during both the rainy and dry seasons. We sequenced the V4 region of 16S rDNA and used multiple R packages to process raw data and performed statistical analysis to reveal the microbial community structure composition and functional predictions. Major dissimilarities between microbial communities were related to seasonality, while healthy and bleached specimens were mainly associated with the enrichment of several less abundant taxa involved in specific metabolic functions, mainly related to the nitrogen cycle. We were not able to observe the dominance of groups that has been previously associated with bleachings, such as Vibrionaceae or Burkholderiaceae. The influx of freshwater appears to increase the homogeneity between individuals in Barra de Santo Antonio, especially during the rainy season. By contrast, we observed an increased homogeneity between samples in Maragogi during the dry season. Understanding the dynamics of the coral microbiota and how bleaching appears in response to specific environmental variables, in addition to determining the conditions that lead to a more robust coral microbiota, is essential for choosing the most appropriate area and conservation methods, for example.

Mass Spectrometry Metabolomics Approach Reveals Anti-Trichomonas vaginalis Scaffolds from Marine Fungi.

Trichomoniasis is the most common non-viral sexually transmitted infection (STI) in the world caused by Trichomonas vaginalis. Failures in the treatment with the 5-nitroimidazole class including parasite resistance to metronidazole elicit new alternatives. Marine natural products are sources of several relevant molecules, presenting a variety of metabolites with numerous biological activities. In this work, we evaluated the anti-T. vaginalis activity of fungi associated with marine invertebrates by mass spectrometry-based metabolomics approaches. After screening of six marine fungi, extract from Penicillium citrinum FMPV 15 has shown to be 100% active against T. vaginalis, and the gel permeation column on Sephadex LH-20® yielded twelve organic fractions which five showed to be active. Metabolomics and statistical analyses were performed with all the samples (extract and fractions), and several compounds were suggested to be related to the activity. These components include citrinin, dicitrinin C, citreoisocoumarin, dihydrocitrinone, decarboxycitrinin, penicitrinone C, and others. The minimum inhibitory concentration (MIC) value of anti-T. vaginalis activity of citrinin was 200 µM. The marine fungi metabolites show potential as new alternatives to overcome drug resistance in T. vaginalis infections.

Multi-omic Analysis of the Gut Microbiome in Rats with Lithium-Pilocarpine-Induced Temporal Lobe Epilepsy.

Evidence supports that the gut microbiota and bacteria-dependent metabolites influence the maintenance of epileptic brain activity. However, the alterations in the gut microbiota between epileptic versus healthy individuals are poorly understood. We used a multi-omic approach to evaluate the changes in the composition of gut metagenome as well in the fecal metabolomic profile in rats before and after being submitted to status epilepticus (SE)-induced temporal lobe epilepsy (TLE). The 16S ribosomal RNA (rRNA) sequencing of fecal samples coupled to bioinformatic analysis revealed taxonomic, compositional, and functional shifts in epileptic rats. The species richness (Chao1 index) was significantly lower in the post-TLE group, and the ß-diversity analysis revealed clustering separated from the pre-TLE group. The taxonomic abundance analysis showed a significant increase of phylum Desulfobacterota and a decrease of Patescibacteria in the post-TLE group. The DESEq2 and LEfSe analysis resulted in 18 genera significantly enriched between post-TLE and pre-TLE groups at the genus level. We observed that epileptic rats present a peculiar metabolic phenotype, including a lower concentration of D-glucose and L-lactic acid and a higher concentration of L-glutamic acid and glycine. The microbiota-host metabolic correlation analysis showed that the genera differentially abundant in post-TLE rats are associated with the altered metabolites, especially the proinflammatory Desulfovibrio and Marvinbryantia, which were enriched in epileptic animals and positively correlated with these excitatory neurotransmitters and carbohydrate metabolites. Therefore, our data revealed a correlation between dysbacteriosis in epileptic animals and fecal metabolites that are known to be relevant for maintaining epileptic brain activity by enhancing chronic inflammation, an excitatory-inhibitory imbalance, and/or a metabolic disturbance. These data are promising and suggest that targeting the gut microbiota could provide a novel avenue for preventing and treating acquired epilepsy. However, the causal relationship between these microbial/metabolite components and the SRS occurrence still needs further exploration.

Tremella ananatis sp. nov. and Tremella lamprococci sp. nov., two yeast species associated with bromeliads.

Eight yeast isolates with an affinity to the genus Tremella were obtained from bromeliads from different locations in Brazil. Although the formation of basidia and basidiocarp were not observed, on the basis of the results of sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and internal transcribed spacer (ITS) region, we suggest that these isolates represent two novel species of the genus Tremella. These yeasts are phylogenetically related to Tremella saccharicola and Tremella globispora. Therefore, we propose Tremella ananatis sp. nov. and Tremella lamprococci sp. nov. as novel yeast species of the order Tremellales (Agaricomycotina, Basidiomycota). Sequence analysis revealed that Tremella ananatis sp. nov. differs by 11 and 28 nucleotide substitutions from Tremella saccharicola in the D1/D2 sequence and ITS region, respectively. Moreover, Tremella lamprococci sp. nov. differs by 15 and 29 nucleotide substitutions from Tremella globispora in the D1/D2 sequence and ITS region, respectively. The holotypes of Tremella ananatis sp. nov. and Tremella lamprococci sp. nov. are CBS 14568T and CBS 14567T, and the MycoBank numbers are MB840480 and MB840481, respectively.

Anti-Trichomonas vaginalis activity and chemical analysis of metabolites produced by marine-associated fungi.

Trichomoniasis is the most common non-viral sexually transmitted infection worldwide and it may have serious consequences, especially for women. Currently, 5-nitroimidazole drugs are the treatment of choice for trichomoniasis, although presenting adverse effects and reported cases of drug resistance. Metabolites isolated from marine fungi have attracted considerable attention due to their unique chemical structures with diverse biological activities, including antiprotozoal activity. In this study, we showed the anti-Trichomonas vaginalis activity of fractions obtained from marine fungi and the chemical composition of the most active fraction was determined. Ethyl acetate fractions of the fungus Aspergillus niger (EAE03) and Trichoderma harzianum/Hypocrea lixii complex (EAE09) were active against T. vaginalis. These samples, EAE03 and EAE09, were also effective against the fresh clinical isolate metronidazole-resistant TV-LACM2R, presenting MIC values of 2.0 mg/mL and 1.0 mg/mL, respectively. The same MIC values were found against ATCC 30,236 T. vaginalis isolate. In vitro cytotoxicity revealed only the fraction named EAE03 with no cytotoxic effect; however, the active fractions did not promote a significant hemolytic effect after 1-h incubation. Already, the in vivo toxicity evaluation using Galleria mellonella larvae demonstrated that none of the tested samples caused a reduction in animal survival. The fraction EAE03 was followed for purification steps and analyzed by LC-DAD-MS. Eleven compounds were annotated, including butyrolactone, butanolide, and atromentin. Overall, the range of activities reported confirms the potential of marine fungi to produce bioactive molecules.

Prevalence, antifungal susceptibility and virulence determinants of oral yeast species isolated from immunodeficient patients in Northeastern Brazil / Prevalência, suscetibilidade a antifúngicos e determinantes de virulência de leveduras orais isoladas de pacientes imunodeficientes do Nordeste do Brasil / Prevalencia, susceptibilidad antifúngica y determinantes de virulencia de levaduras orales aisladas de pacientes inmunodeficientes del Noreste de Brasil

Justificativa e Objetivos: A candidíase oral tem uma ocorrência comum em pacientes imunocomprometidos. No entanto, outras infecções emergentes tornaram-se cada vez mais habituais. O objetivo deste estudo foi investigar a prevalência, os determinantes de virulência e a suscetibilidade a antifúngicos de leveduras que colonizam a mucosa de pacientes imunocomprometidos na região Nordeste do Brasil. Métodos: A amostra foi composta por 60 pacientes HIV positivos atendidos no Serviço de Atendimento Especializado/Hospital Dia do Hospital Universitário Prof. Alberto Antunes, vinculado à Universidade Federal de Alagoas. As amostras foram coletadas em regiões subgengivais e semeadas em CHROMagar para confirmação presuntiva de Candida spp., seguido por PCR e sequenciamento. Além disso, testamos os determinantes de virulência fosfolipase e protease e avaliamos in vitro a concentração inibitória mínima dos antifúngicos anfotericina B e fluconazol. Este projeto foi aprovado pelo Comitê de ética em pesquisa do Centro de Estudos Superiores de Maceió. Resultados: Aproximadamente 63% dos pacientes foram colonizados por leveduras. A espécie C. albicans foi predominante, enquanto as espécies de Candida não-albicans representaram 49% dos isolados, sendo C. dubliniensis e C. parapsilosis as mais comuns. Entretanto, C. intermedia, Bullera penniseticola e Naganishia liquefaciens também foram encontrados. Os determinantes da virulência protease e/ou fosfolipase também foram produzidos por Candida spp. e alguns isolados oportunistas incomuns como Kodamaea ohmeri, N. liquefaciens e Saitozyma podzolica. Além disso, a maioria dos isolados de Candida spp. e algumas espécies oportunistas incomuns apresentaram altos valores de concentração inibitória mínima. Conclusão: Os resultados obtidos indicam que C. albicans continua a ser a espécie predominante na cavidade oral de pacientes imunodeficientes e, juntamente com outras espécies incomuns, pode apresentar alta resistência aos antifúngicos testados.(AU)

Background and Objectives: Oral candidiasis has a common occurrence in immunocompromised patients. However, other emergent infections have become increasingly common. The aim of this study was to investigate the prevalence, virulence determinants and the antifungal susceptibility of yeast colonizing the mucosa of immunocompromised patients in Northeastern Brazil. Methods: Samples from sixty HIV-positive patients seen at the Specialized Service / Hospital Dia - Hospital Universitário Prof. Alberto Antunes from the Federal University of Alagoas were collected from subgingival sites and seeded on CHROMagar for presumptive confirmation of Candida spp. followed by PCR and sequencing. In addition, we tested virulence determinants, phospholipase and protease and evaluated in vitro the Minimum Inhibitory Concentration of antifungals amphotericin B and fluconazole. This project was approved by the Research Ethics Committee of the Center for Higher Studies in Maceió. Results: Approximately 63% of the patients were colonized by yeasts, with C. albicans as the predominant species, while non-Candida albicans species accounted for 49% of the isolates, with C. dubliniensis and C. parapsilosis being the commonest, but C. intermedia, Bullera penniseticola and Naganishia liquefaciens were also found. The virulence determinants protease and/or phospholipase were also produced by Candida spp. and some uncommon opportunistic isolates such as Kodamaea ohmeri, N. liquefaciens and Saitozyma podzolica. Furthermore, most of Candida spp. strains and some uncommon opportunistic species showed high values of minimal inhibitory concentration. Conclusion: Results obtained indicate that C. albicans continues to be the predominant species in oral cavity of immunodeficient patients and along with other unusual species may present high resistance to the antifungals tested.(AU)

Justificación y Objetivos: La candidiasis oral acomete con frecuencia a pacientes inmunocomprometidos. Sin embargo, otras infecciones emergentes se han vuelto cada vez más comunes. El objetivo de este estudio fue investigar la prevalencia, la producción de determinantes de virulencia y la susceptibilidad a antifúngicos de levaduras que colonizan la mucosa de pacientes inmunocomprometidos en la región Nordeste de Brasil. Métodos: Se colectaron muestras de sesenta pacientes VIH positivos atendidos en el Servicio de Atención Especializado/Hospital Día del Hospital Universitario Prof. Alberto Antunes, vinculado a la Universidad Federal de Alagoas. Se colectaron las muestras en las regiones subgingivales y las sembraron en CHROMagar para la presunta confirmación de Candida spp. seguido de PCR y secuenciación. Además, analizamos los determinantes de virulencia fosfolipasa y proteasa y evaluamos in vitro la concentración mínima inhibitoria de los antifúngicos anfotericina B y fluconazol. Este proyecto fue aprobado por el Comité de Ética en Investigación del Centro de Estudios Superiores de Maceió. Resultados: Aproximadamente el 63% de los pacientes fueron colonizados por levaduras, y la C. albicans fue la especie predominante, mientras que las especies de Candida no-albicans representaron el 49% de los aislamientos, de las cuales la C. dubliniensis y la C. parapsilosis fueron las más comunes. Sin embargo, también se encontraron C. intermedia, Bullera penniseticola y Naganishia liquefaciens. Los determinantes de virulencia de proteasa y/o fosfolipasa también fueron producidos por Candida spp. y algunos aislados oportunistas inusuales como Kodamaea ohmeri, N. liquefaciens y Saitozyma podzolica. Además, la mayoría de los asilados de Candida spp. y algunas especies oportunistas inusuales mostraron valores altos de concentración mínima inhibitoria. Conclusión: Los resultados obtenidos indican que C. albicans continúa siendo la especie predominante en la cavidad oral de pacientes inmunodeprimidos y, junto con otras especies poco comunes, puede presentar una alta resistencia a los antifúngicos evaluados.(AU)

Bacterial community and environmental factors associated to rivers runoff and their possible impacts on coral reef conservation.

Rivers potentially conduct important components as result of anthropogenic stressors for coral reefs. Molecular techniques are increasingly being used for monitoring biological and chemical monitoring of rivers and reefs. Here, we use PhyloChips™ to process surface water samples collected along two rivers and associated reefs in an environmental protection area in northeastern Brazil. Our results indicate that a significant part of Operational Taxonomic Units (OTUs) identified were able to survive the transition from freshwater to seawater, several of them belonging to genera implicated in human pathogenesis. The BBC:A ratio and functional prediction suggests that both study rivers are subject to fecal contamination and xenobiotics input and that the bacterial communities were more homogeneous in these environments. We suggest that protection actions adopted for reefs should be broadly extended to the surrounding environment, and that other bacterial group (besides cultivable coliforms) should be included in routine water quality monitoring.

Vishniacozyma alagoana sp. nov. a tremellomycetes yeast associated with plants from dry and rainfall tropical forests.

Plants are important reservoirs of described and undescribed species of yeast. During a study of yeasts associated with bromeliads from the Northeast region of Brazil (collected in 2013-2017), analysis of the D1/D2 domain of the LSU rRNA and internal transcribed spacer (ITS) region identified eleven strains of yeasts as representing an unknown species of the genus Vishniacozyma. The species may have a diverse habitat in Brazil as a strain was collected from a flowering plant (Acanthaceae) in 1994. As a consequence, we propose Vishniacozyma alagoana sp. nov. as a member of the tremellomycetes yeasts (Agaricomycotina, Basidiomycota). Vishniacozyma alagoana sp. nov. was found in Atlantic Forest (a tropical rainforest) and the Caatinga (a seasonally dry tropical forest) associated with bromeliads in northeast and southeastern Brazil. The proposed novel species is related to Vishniacozyma taibaiensis and distinguished by eight nucleotide substitutions in the D1/D2 domain and seventeen in the ITS region. In addition, Vishniacozyma alagoana sp. nov. differs from V. taibaiensis by the ability to assimilate ribitol. The holotype is CBS 15966T.

Diversity of culturable yeasts associated with zoanthids from Brazilian reef and its relation with anthropogenic disturbance.

Some of the main threats to coral reefs come from human actions on marine environment, such as tourism, overfishing and pollution from urban development. While several studies have demonstrated an association between bacteria and corals, demonstrating how these communities react to different anthropogenic stressors, yeast communities associated with corals have received far less attention from researchers. The aim of this work was therefore to describe cultivable yeasts associated with three coral species and to evaluate the influence of sewage discharge on yeasts community. We obtained 130 isolates, mostly belonging to phylum Ascomycota and many of them had previously been isolated from human samples or are considered pathogens. The mycobiota was more similar among corals collected from the same reef, indicating that the composition of reef yeast community is more influenced by environmental conditions than host species. We suggest further studies to elucidate which factors are most influential on the composition of the coral-associated yeast community.

Carlosrosaea hohenbergiae sp. nov. and Carlosrosaea aechmeae sp. nov., two tremellaceous yeasts isolated from bromeliads in north-eastern Brazil.

Yeast surveys associated with different bromeliads in north-eastern Brazil led to the proposal of two novel yeast species, Carlosrosaea hohenbergiae sp. nov. and Carlosrosaea aechmeae sp. nov., belonging to the Tremellales clade (Agaricomycotina, Basidiomycota). Analysis of the sequences of the internal transcribed spacer (ITS) region and D1/D2 domain of the LSU rRNA gene suggested an affinity with a phylogenetic lineage that includes recently reclassified Carlosrosaeavrieseae. Six isolates of the novel species were obtained from different bromeliad species collected in three Atlantic Forest fragments in Alagoas state, Brazil. Ca. hohenbergiae sp. nov. differs by 69 and 12 nucleotide substitutions in the ITS and D1/D2 domain, respectively, from Ca. vrieseae. The type strain is UFMG-CM-Y405T (=BSB 34T=CBS 14563T), Mycobank 819227. Ca. aechmeae sp. nov. is represented by one strain isolated from Aechmea constantinii leaves. Ca. aechmeae sp. nov. differs from the related species Ca. hohenbergiae and Ca. vrieseae by 36 and 65 nucleotide substitutions, respectively, in the ITS region and by 12 and 15 nucleotide substitutions in the D1/D2 domain, respectively. The type strain of Ca. aechmeae sp. nov. is UFMG-CM-Y6095T (=BM 94T=CBS 14578), Mycobank 819228.

Compositional shifts in bacterial communities associated with the coral Palythoa caribaeorum due to anthropogenic effects.

Corals harbor abundant and diverse prokaryotic communities that may be strongly influenced by human activities, which in turn compromise the normal functioning of coral species and predispose them to opportunistic infections. In this study, we investigated the effect of sewage dumping on the bacterial communities associated with the soft coral Palythoa caribaeorum at two sites in the Brazilian coast. We observed a dominance of bacterial species classified as human pathogens at sites exposed to untreated sewage discharge. The microbial diversity of undisturbed sites was more homogeneous and diverse and showed greater abundance. In addition, bacterial communities differed substantially between the exposed and undisturbed areas. The microbial community associated with the samples collected from the exposed sites revealed the anthropogenic effect caused by organic matter from untreated sewage dumping, with an abundance of pathogenic bacterial species.

Indels ascertain the phylogenetic position of Coleodactylus elizae Gonçalves, Torquato, Skuk & Sena, 2012 (Gekkota: Sphaerodactylidae).

The Neotropical gecko genus Coleodactylus Parker 1926 was, until recently, composed of five species: C. amazonicus (Andersson 1918), C. brachystoma (Amaral 1935), C. meridionalis (Boulenger 1888), C. natalensis Freire 1999, and C. septentrionalis Vanzolini 1980 (Geurgas et al. 2008). However, several phylogenetic analyses recovered a polyphyletic Coleodactylus (Geurgas et al. 2008; Gamble et al. 2011a) leading Gamble et al. (2011b) to recognize a new genus, Chatogekko, for C. amazonicus. Coleodactylus and Chatogekko differ in both morphological and molecular characters. Coleodactylus has smooth dorsal scales and five scales forming the ungual sheath, while Chatogekko has keeled dorsal scales and four scales forming the ungual sheath (Gamble et al. 2011b). Furthermore, all Coleodactylus species have two deletions in the protein coding recombination-activating gene 1 (RAG1), one of six base pairs (bp) and another of 18 bp (Gamble et al. 2008a; Geurgas et al. 2008), while Chatogekko has a unique three bp deletion in the RBMX gene and a three bp deletion in the protein tyrosine phosphatase nonreceptor type 12 gene (PTPN12) (Gamble et al. 2011b). In addition, Chatogekko is differentiated from all others geckos by a unique set of 10 craniofacial features (Gamble et al. 2011b).

Susceptibility to antifungal agents and enzymatic activity of Candida haemulonii and Cutaneotrichosporon dermatis isolated from soft corals on the Brazilian reefs.

Candida is a common fungus with the capacity to cause infections in humans. However, most studies have concentrated on clinical isolates and little is known about the identity, ecology and drug resistance of free living species/strains. Here, we isolate eight strains of Candida haemulonii and four strains of Cutaneotrichosporon dermatis from three marine cnidarian zoanthids species (Palythoa caribaeorum, Palythoa variabilis and Zoanthus sociatus) collected from Brazilian coral reefs. Strains were identified by sequencing of the D1/D2 domain LSU rDNA and ITS region. We tested these environmental isolates for their capacity to grow in media with increasing concentration of NaCl, capacity to grow in different temperatures, enzymatic activity and antifungal susceptibility. For C. haemulonii, all strains strongly produced gelatinase, esterase and albuminase and were either able to express lipase, phospholipase and keratinase, but not express urease and DNase. The strains were able to grow at 37 °C, but not at 39 °C, and except for LMS 40, all of them could grow in a 10 % NaCl medium. All isolates were resistant to all antifungals tested, with exception for ketoconazole and tioconazole (MIC = 2 µg/mL). For C. dermatis, all strains could grow at 39 °C and could not express phospholipase, keratinase or gelatinase. However, all were capable of expressing urease, lipase and esterase. Three out of four strains could grow in a 10 % NaCl medium, but none grew in a 30 % NaCl medium. The strains showed high values of minimal inhibitory concentration. LMPV 90 was resistant to tioconazole, terbinafine, fluconazole and posaconazole, and LMS 38 was resistant to all antifungal agents tested. We discuss the characterization of C. haemulonii and C. dermatis as a possible emerging pathogen due to its animal-related enzymatic arsenal and antifungal resistance.

Enzymatic Activity and Susceptibility to Antifungal Agents of Brazilian Environmental Isolates of Hortaea werneckii.

Four strains of Hortaea werneckii were isolated from different substrates in Brazil (a salt marsh macrophyte, a bromeliad and a marine zoanthid) and had their identification confirmed by sequencing of the 26S rDNA D1/D2 domain or ITS region. Most of the strains were able to express amylase, lipase, esterase, pectinase and/or cellulase, enzymes that recognize components of plant cells as substrates, but did not express albuminase, keratinase, phospholipase and DNAse, whose substrates are animal-related. Urease production was positive for all isolates, while caseinase, gelatinase and laccase production were variable among the strains. All the strains grew in media containing up to 30% NaCl. We propose that the primary substrate associated with H. werneckii is plant-related, in special in saline environments, where the fungus may live as a saprophyte and decomposer. Infection of animal-associated substrates would be secondary, with the fungus acting as an opportunistic animal pathogen. All strains were resistant to fluconazole and presented high MIC for amphotericin B, while they were susceptible to all the other antifungal agents tested.

Bullera vrieseae sp. nov., a tremellaceous yeast species isolated from bromeliads.

Two independent surveys of yeasts associated with different bromeliads in different Brazilian regions led to the proposal of a novel yeast species, Bullera vrieseae sp. nov., belonging to the Tremellales clade (Agaricomycotina, Basidiomycota). Analysis of the sequences in the internal transcribed spacer (ITS) region and D1/D2 domain of the LSU rRNA gene suggested affinity to a phylogenetic lineage that includes Bullera miyagiana and Bullera sakaeratica. Six isolates of the novel species were obtained from different bromeliads and regions in Brazil. Sequence analysis of the D1/D2 domains of the large subunit of the rRNA gene showed that the novel species differs from B. miyagiana and B. sakaeratica by 85 and 64 nt substitutions, respectively and by more than 75 nt substitutions in the ITS region. Phenotypically, Bullera vrieseae sp. nov. can be distinguished from both species based on the assimilation of meso-erythritol, which was negative for B. vrieseae sp. nov. but positive for the others, assimilation of d-glucosamine, which was positive for B. vrieseae sp. nov. but negative for B. miyagiana and of l-sorbose, which was negative for B. vrieseae sp. nov. but positive for B. sakaeratica. The novel species Bullera vrieseae sp. nov. is proposed to accommodate these isolates. The type strain of Bullera vrieseae sp. nov. is UFMG-CM-Y379T (BRO443T; ex-type CBS 13870T).

Hannaella pagnoccae sp. nov., a tremellaceous yeast species isolated from plants and soil.

Several independent surveys of yeasts associated with different plant materials and soil led to the proposal of a novel yeast species belonging to the Tremellales clade (Agaricomycotina, Basidiomycota). Analysis of the sequences of the D1/D2 domains and internal transcribed spacer region of the large subunit of the rRNA gene suggested affinity to a phylogenetic lineage that includes Hannaella coprosmaensis, Hannaella oryzae and Hannaella sinensis. Thirty-two isolates were obtained from different sources, including bromeliads, nectar of Heliconia psittacorum (Heliconiaceae), flowers of Pimenta dioica (Myrtaceae), roots and leaves of sugar cane (Saccharum spp.) in Brazil, leaves of Cratoxylum maingayi, Arundinaria pusilla and Vitis vinifera in Thailand, soil samples in Taiwan, and prairie soil in the USA. Sequence analysis of the D1/D2 domains of the large subunit of the rRNA gene showed that the novel species differs from Hannaella coprosmaensis and Hannaella oryzae by 36 and 46 nt substitutions, respectively. A novel species is suggested to accommodate these isolates, for which the name Hannaella pagnoccae sp. nov. is proposed. The type strain is BI118(T) ( = CBS 11142(T) = ATCC MYA-4530(T)).

Susceptibility of species within the Sporothrix schenckii complex to a panel of killer yeasts.

The Sporothrix schenckii complex is the etiologic agent of sporotrichosis, a subacute or chronic mycosis which can affect humans and animals. Killer yeasts have been used in the medical field for development of novel antimycotics and biotyping of pathogenic fungi. The action of 18 killer yeasts on the growth of 88 characterized S. schenckii, Sporothrix globosa, Sporothrix brasiliensis, and Sporothrix mexicana clinical and environmental isolates was evaluated. Killer studies were performed on Petri dishes containing cheese black starch agar. The yeasts Candida catenulata (QU26, QU31, QU127, LV102); Trichosporon faecale (QU100); Trichosporon japonicum (QU139); Kluyveromyces lactis (QU30, QU99, QU73); Kazachstania unispora (QU49), Trichosporon insectorum (QU89), and Kluyveromyces marxianus (QU103) showed activity against all strains of the S. schenckii complex tested. Observation by optical microscopy of S. brasiliensis 61 within the inhibition haloes around the colonies of the killer yeasts QU100, QU139, and LV102 showed that there was no conidiation, but there was hyphal proliferation. The toxins were fungistatic against S. brasiliensis 61. There was no difference in susceptibility to the toxins among the S. schenckii species complex. Further investigations are necessary to clearly establish the mechanism of action of the toxins.

Isolation and genotyping of free-living environmental isolates of Acanthamoeba spp. from bromeliads in Southern Brazil.

Species of Acanthamoeba are frequently isolated from distinct environmental sources such as water, soil, dust and air. They are responsible to cause infections and disease in humans and animals. In addition, Acanthamoeba sp. are considered an important reservoir of bacteria, virus and fungi, which act as "Trojan horses" to protect these microorganisms of harsh environmental conditions. In this study, nine Acanthamoeba isolates from bromeliads phylloplane were identified based on the morphology of cyst and trophozoite forms. The genotype level was accessed by the sequence analysis of Acanthamoeba small-subunit rRNA gene. Genotypic characterization grouped five isolates in the genotype T2/T6, three in the T4 genotype and one in the genotype T16. The results obtained indicate that the genotype T2/T6 is common on phylloplane. To predict the pathogenic potential of the Acanthamoeba isolates, thermo and osmotolerance assays were employed, although all isolates were capable of surviving at temperatures of 37°C, other tests will be conducted in the future to determine the potential pathogenic of the isolates. Altogether, our results revealed the importance of the presence of Acanthamoeba associated with bromeliads in Rio Grande do Sul, Brazil, and the necessity for further studies to determine the environmental distribution and the role of these species.

Bandoniozyma gen. nov., a genus of fermentative and non-fermentative tremellaceous yeast species.

BACKGROUND: Independent surveys across the globe led to the proposal of a new basidiomycetous yeast genus within the Bulleromyces clade of the Tremellales, Bandoniozyma gen. nov., with seven new species. METHODOLOGY/PRINCIPAL FINDINGS: The species were characterized by multiple methods, including the analysis of D1/D2 and ITS nucleotide sequences, and morphological and physiological/biochemical traits. Most species can ferment glucose, which is an unusual trait among basidiomycetous yeasts. CONCLUSIONS/SIGNIFICANCE: In this study we propose the new yeast genus Bandoniozyma, with seven species Bandoniozyma noutii sp. nov. (type species of genus; CBS 8364(T)  =  DBVPG 4489(T)), Bandoniozyma aquatica sp. nov. (UFMG-DH4.20(T)  =  CBS 12527(T)  =  ATCC MYA-4876(T)), Bandoniozyma complexa sp. nov. (CBS 11570(T)  =  ATCC MYA-4603(T)  =  MA28a(T)), Bandoniozyma fermentans sp. nov. (CBS 12399(T)  =  NU7M71(T)  =  BCRC 23267(T)), Bandoniozyma glucofermentans sp. nov. (CBS 10381(T)  =  NRRL Y-48076(T)  =  ATCC MYA-4760(T)  =  BG 02-7-15-015A-1-1(T)), Bandoniozyma tunnelae sp. nov. (CBS 8024(T)  =  DBVPG 7000(T)), and Bandoniozyma visegradensis sp. nov. (CBS 12505(T)  =  NRRL Y-48783(T)  =  NCAIM Y.01952(T)).