Microbiologia
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11840
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Resultados da Pesquisa
Item Purification and characterization of two new cell-bound bioactive compounds produced by wild Lactococcus lactis strain(FEMS Microbiology Letters, 2017-06) Saraiva, Margarete Alice Fontes; Brede, Dag Anders; Nes, Ingolf Figved; Baracat- Pereira, Maria Cristina; Queiroz, Marisa Vieira de; Moraes, Celia Alencar deNovel compounds and innovative methods are required considering that antibiotic resistance has reached a crisis point. In the study, two cell-bound antimicrobial compounds produced by Lactococcus lactis ID1.5 were isolated and partially characterized. Following purification by cationic exchange and a solid-phase C18 column, antimicrobial activity was recovered after three runs of RPC using 60% (v/v) and 100% (v/v) of 2-propanol for elution, suggesting that more than one antimicrobial compound were produced by L. lactis ID1.5, which were in this study called compounds AI and AII. The mass spectrum of AI and AII showed major intensity ions at m/z 1070.05 and 955.9 Da, respectively. The compound AI showed a spectrum of antimicrobial activity mainly against L. lactis species, while the organisms most sensitive to compound AII were Bacillus subtilis, Listeria innocua, Streptococcus pneumoniae and Pseudomonas aeruginosa. The antimicrobial activity of both compounds was suppressed by treatment with Tween 80. Nevertheless, both compounds showed high stability to heat and proteases treatments. The isolated compounds, AI and AII, showed distinct properties from other antimicrobial substances already reported as produced by L. lactis, and have a significant inhibitory effect against two clinically important respiratory pathogens.Item Screening of yeasts isolated from brazilian environments for the 2-Phenylethanol (2-PE) production(Biotechnology and Bioprocess Engineering, 2018-06) Lima, Lorena Azevedo de; Diniz, Raphael Hermano Santos; Queiroz, Marisa Vieira de; Fietto, Luciano Gomes; Silveira, Wendel Batista daPhenylethanol alcohol, or 2-phenylethanol (2-PE) production by yeasts has been considered a promising alternative to its chemical synthesis. In order to evaluate the potential of yeast strains isolated from different Brazilian environments, we evaluated the 2-PE production of 267 strains. Among them, the Kluyveromyces marxianus CCT 7735 yeast stood out as being the best 2-PE producer. The K. marxianus CCT 7735 growth was impaired by 2-PE; nevertheless, this effect is less pronounced than the inhibition reported for certain Saccharomyces cerevisiae strains. The maximum 2-PE titer obtained under optimized conditions was 3.44 g/L, 28% higher than the titer achieved under unoptimized conditions. The optimized conditions were: 30ºC, and glucose and L-phe concentrations of 3.0 and 4.0 g/L, respectively. Moreover, the specific production rate of 2-PE increased twofold compared to the unoptimized conditions.Item A look into a multifunctional toolbox: endophytic Bacillus species provide broad and underexploited benefits for plants(World Journal of Microbiology and Biotechnology, 2018-06-13) Queiroz, Marisa Vieira de; Lopes, Ralf; Tsui, Sarina; Gonçalves, Priscila J. R. O.One of the major challenges of agriculture currently is to obtain higher crop yield. Environmental conditions, cultivar quality, and plant diseases greatly affect plant productivity. On the other hand, several endophytic Bacillus species have emerged as a complementary, efficient, and safe alternative to current crop management practices. The ability of Bacillus species to form spores, which resist adverse conditions, is an advantage of the genus for use in formulations. Endophytic Bacillus species provide plants with a wide range of benefits, including protection against phytopathogenic microorganisms, insects, and nematodes, eliciting resistance, and promoting plant growth, without causing damage to the environment. Bacillus thuringiensis, B. subtilis, B. amyloliquefaciens, B. velezensis, B. cereus, B. pumilus, and B. licheniformis are the most studied Bacillus species for application in agriculture, although other species within the genus have also shown great potential. Due to the increasing number of whole-genome sequenced endophytic Bacillus spp. strains, various bioactive compounds have been predicted. These data reveal endophytic Bacillus species as an underexploited source of novel molecules of biotechnological interest. In this review, we discuss how endophytic Bacillus species are a valuable multifunctional toolbox to be integrated with crop management practices for achieving higher crop yield.Item A look into a multifunctional toolbox: endophytic Bacillus species provide broad and underexploited benefits for plants(World Journal of Microbiology and Biotechnology, 2018-06-13) Queiroz, Marisa Vieira de; Gonçalves, Priscila J. R. O.; Lopes, Ralf; Tsui, SarinaOne of the major challenges of agriculture currently is to obtain higher crop yield. Environmental conditions, cultivar quality, and plant diseases greatly affect plant productivity. On the other hand, several endophytic Bacillus species have emerged as a complementary, efficient, and safe alternative to current crop management practices. The ability of Bacillus species to form spores, which resist adverse conditions, is an advantage of the genus for use in formulations. Endophytic Bacillus species provide plants with a wide range of benefits, including protection against phytopathogenic microorganisms, insects, and nematodes, eliciting resistance, and promoting plant growth, without causing damage to the environment. Bacillus thuringiensis, B. subtilis, B. amyloliquefaciens, B. velezensis, B. cereus, B. pumilus, and B. licheniformis are the most studied Bacillus species for application in agriculture, although other species within the genus have also shown great potential. Due to the increasing number of whole-genome sequenced endophytic Bacillus spp. strains, various bioactive compounds have been predicted. These data reveal endophytic Bacillus species as an underexploited source of novel molecules of biotechnological interest. In this review, we discuss how endophytic Bacillus species are a valuable multifunctional toolbox to be integrated with crop management practices for achieving higher crop yield.Item New Lager Brewery Strains obtained by crossing techniques using cachaça (Brazilian Spirit) yeasts(Applied and Environmental Microbiology, 2017-08-04) Queiroz, Marisa Vieira de; Figueiredo, Bruna Inez Carvalho; Saraiva, Margarete Alice Fontes; Pimenta, Paloma Patrick de Souza; Testasicca, Miriam Conceição de Souza; Sampaio, Geraldo Magela Santos; Cunha, Aureliano Claret da; Afonso, Luis Carlos Crocco; Castro, Ieso de Miranda; Brandão, Rogelio LopesThe development of hybrids has been an effective approach to generate novel yeast strains with optimal technological profile for use in beer production. This study describes the generation of a new yeast strain for lager beer production by direct mating between two Saccharomyces cerevisiae strains isolated from cachaça distilleries: one that was strongly flocculent, and the other with higher production of acetate esters. The first step in this procedure was to analyze the sporulation ability and reproductive cycle of strains belonging to a specific collection of yeasts isolated from cachaça fermen- tation vats. Most strains showed high rates of sporulation, spore viability, and homothal- lic behavior. In order to obtain new yeast strains with desirable properties useful for la- ger beer production, we compare haploid-to-haploid and diploid-to-diploid mating procedures. Moreover, an assessment of parental phenotype traits showed that the seg- regant diploid C2-1d generated from a diploid-to-diploid mating experiment showed good fermentation performance at low temperature, high flocculation capacity, and de- sirable production of acetate esters that was significantly better than that of one type la- ger strain. Therefore, strain C2-1d might be an important candidate for the production of lager beer, with distinct fruit traces and originating using a non-genetically modified organism (GMO) approach. Recent work has suggested the utilization of hybridization techniques for the generation of novel non-genetically modified brewing yeast strains with combined properties not commonly found in a unique yeast strain. We have observed remarkable traits, especially low temperature tolerance, maltotriose utilization, flocculation ability, and production of volatile aroma compounds, among a collection of Saccharomyces cerevisiae strains isolated from cachaça distilleries, which allow their utilization in the production of beer. The significance of our research is in the use of breeding/hybridization techniques to generate yeast strains that would be appropriate for producing new lager beers by exploring the capacity of cachaça yeast strains to flocculate and to ferment maltose at low temperature, with the concomitant production of flavoring compounds.Item Análise comparativa do genoma mitocondrial do fungo Colletotrichum lindemuthianum, agente causal da antracnose em feijão comum(Applied Microbiology and Biotechnology, 2018-02-16) Queiroz, Casley Borges de; Santana, Mateus Ferreira; Vidigal, Pedro M. Pereira; Queiroz, Marisa Vieira deFungi of the genus Colletotrichum are economically important and are used as models in plant-pathogen interaction studies. In this study, the complete mitochondrial genomes of two Colletotrichum lindemuthianum isolates were sequenced and compared with the mitochondrial genomes of seven species of Colletotrichum. The mitochondrial genome of C. lindemuthianum is a typical circular molecule 37,446 bp (isolate 89 A2 2-3) and 37,440 bp (isolate 83.501) in length. The difference of six nucleotides between the two genomes is the result of a deletion in the ribosomal protein S3 (rps3) gene in the 83.501 isolate. In addition, substitution of adenine for guanine within the rps3 gene in the mitochondrial genome of the 83.501 isolate was observed. Compared to the previously sequenced C. lindemuthianum mitochondrial genome, an exon no annotated in the cytochrome c oxidase I (cox1) gene and a non-conserved open reading frame (ncORF) were observed. The size of the mitochondrial genomes of the seven species of Colletotrichum was highly variable, being attributed mainly to the ncORF, ranging from one to 10 and also from introns ranging from one to 11 and which encode a total of up to nine homing endonucleases. This paper reports for the first time by means of transcriptome that then ncORFs are transcribed in Colletotrichum spp. Phylogeny data revealed that core mitochondrial genes could be used as an alternative in phylogenetic relationship studies in Colletotrichum spp. This work contributes to the genetic and biological knowledge of Colletotrichum spp., which is of great economic and scientific importance.Item Draft genome sequences of two isolates of colletotrichum lindemuthianum, the causal agent of anthracnose in common beans(Genome Announcements, 2017-03-15) Queiroz, Casley Borges de; Correia, Hilberty L. Nunes; Menicucci, Renato Pedrozo; Vidigal, Pedro M. Pereira; Queiroz, Marisa Vieira deColletotrichum lindemuthianum is the causal agent of anthracnose in common beans, one of the main limiting factors of their culture. Here, we report for the first time, to our knowledge, a draft of the complete genome sequences of two isolates belonging to 83.501 and 89 A2 2-3 of C. lindemutuianum.Item Genome analysis reveals insights of the endophytic Bacillus toyonensis BAC3151 as a potentially novel agent for biocontrol of plant pathogens(World Journal of Microbiology and Biotechnology, 2017-09-25) Lopes, Ralf; Cerdeira, Louise; Tavares, Grace S.; Ruiz, Jeronimo C.; Blom, Jochen; Horácio, Elvira C. A.; Mantovani, Hilário C.; Queiroz, Marisa Vieira deDiseases caused by phytopathogenic microorganisms account for enormous losses for agribusiness. Although Bacillus species are recognized as being antimicrobial producers and some may provide benefits to plants, the association between Bacillus toyonensis and plants has not been studied. In this study, the whole-genome sequenced endophytic B. toyonensis BAC3151, which has demonstrated antimicrobial activity and quorum sensing inhibition of phytopathogenic bacteria, was investigated for its potential for the production of compounds for biocontrol of plant pathogens. Four whole-genome sequenced B. toyonensis strains shared 3811 protein-coding DNA sequences (CDSs), while strain-specific CDSs, such as biosynthetic gene clusters of antimicrobials, were associated with specific chromosomal regions and mobile genetic elements of the strains. B. toyonensis strains had a higher frequency of putative bacteriocins gene clusters than that of Bacillus species traditionally used for the production of antimicrobials. In addition, gene clusters potentially involved in the production of novel bacteriocins were found in BAC3151, as well as biosynthetic genes of several other compounds, including non-ribosomal peptides, N-acyl homoserine lactonase and chitinases, revealing a genetic repertoire for antimicrobial synthesis greater than that of other Bacillus strains that have demonstrated effective activity against phytopathogens. This study showed for the first time that B. toyonensis has potential to produce various antimicrobials, and the analyses performed indicated that the endophytic strain BAC3151 can be useful for the development of new strategies to control microbial diseases in plants that are responsible for large damages in agricultural crops.Item Draft genome sequences of two isolates of colletotrichuml indemuthianum, the causal agent of anthracnose in common beans(Genome Announcements, 2017-05-04) Queiroz, Casley Borges de; Correia, Hilberty L. Nunes; Menicucci, Renato Pedrozo; VidigaL, Pedro M. Pereira; Queiroz, Marisa Vieira deColletotrichum lindemuthianum is the causal agent of anthracnose in common beans, one of the main limiting factors of their culture. Here, we report for the first time, to our knowledge, a draft of the complete genome sequences of two isolates belonging to 83.501 and 89 A2 2-3 of C. lindemutuianum.Item Pectin lyase overproduction by Penicillium griseoroseum mutants resistant to catabolite repression(Brazilian Journal of Microbiology, 2017-02-09) Lima, Juliana Oliveira; Pereira, Jorge Fernando; Araújo, Elza Fernandes de; Queiroz, Marisa Vieira deExpression of pectinolytic genes is regulated by catabolic repression limiting the production of pectin lyase (PL) if the natural inducer, pectin, is missing from the growth medium. Here, we report the isolation of Penicillium griseoroseum mutants resistant to 2-deoxy-d-glucose (DG) that show resistance to catabolite repression and overproduce PL. Three spontaneous and nine UV-induced mutants were obtained. Some mutants produced sectors (segments morphologically different) that were also studied. The mutants were analyzed for pectinases production on pectinase-agar plates and five mutants and two sectors showing larger clearing zones than the wild type were selected for quantitative assay. Although PL production higher than the wild type has been found, phenotype instability was observed for most of the mutants and, after transfers to nonselective medium, the DG resistance was no longer present. Only mutants M03 and M04 were stable maintaining the DG-resistance phenotype. When growing for 120 h in liquid medium containing glucose with or without pectin, both mutants showed higher PL production. In the presence of glucose as sole carbon source, the mutant M03 produced 7.8-fold more PL than the wild type. Due its phenotypic stability and PL overproduction, the mutant M03 presents potential for industrial applications.