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José Ramos - One of the best experts on this subject based on the ideXlab platform.
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Salt and oxidative stress tolerance in Debaryomyces hansenii and Debaryomyces fabryi
FEMS yeast research, 2012Co-Authors: Carmen Michán, José L. Martínez, María C. Álvarez, Martina Turk, Hana Sychrová, José RamosAbstract:We report the characterization of five strains belonging to the halotolerant highly related Debaryomyces hansenii/fabryi species. The analysis performed consisted in studying tolerance properties, membrane characteristics, and cation incell amounts. We have specifically investigated (1) tolerance to different chemicals, (2) tolerance to osmotic and salt stress, (3) tolerance and response to oxidative stress, (4) reactive oxygen species (ROS) content, (5) relative membrane potential, (6) cell volume, (7) K+ and Na+ ion content, and (8) membrane fluidity. Unexpectedly, no direct relationship was found between one particular strain, Na+ content and its tolerance to NaCl or between its ROS content and its tolerance to H2O2. Results show that, although in general, human origin D.fabryi strains were more resistant to oxidative stress and presented shorter doubling times and smaller cell volume than food isolated D.hansenii ones, strains belonging to the same species can be significantly different. Debaryomyces fabryi CBS1793 strain highlighted for its extremely tolerant behavior when exposed to the diverse stress factors studied.
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Oxidative stress sensitivity in Debaryomyces hansenii
FEMS yeast research, 2009Co-Authors: Clara Navarrete, José L. Martínez, Alicia Siles, Fernando Calero, José RamosAbstract:Debaryomyces hansenii is an osmotolerant and halotolerant yeast of increasing interest for fundamental and applied research. In this work, we have performed a first study on the effect of oxidative stress on the performance of this yeast. We have used Saccharomyces cerevisiae as a well-known reference yeast. We show that D. hansenii is much more susceptible than S. cerevisiae to cadmium chloride, hydrogen peroxide or 1,4-dithiothreitol. These substances induced the formation of reactive oxygen species (ROS) in both yeasts, the amounts measured being significantly higher in the case of D. hansenii. We also show that NaCl exerted a protective effect against oxidative stress in Debaryomyces, but that this was not the case in Saccharomyces because sodium protected that yeast only when toxicity was induced with cadmium. On the basis of the present results, we raised the hypothesis that the sensitivity to oxidative stress in D. hansenii is related to the high amounts of ROS formed in that yeast and that observations such as low glutathione amounts, low basal superoxide dismutase and peroxidase activities, decrease in ATP levels produced in the presence of ROS inducers and high cadmium accumulation are determinants directly or indirectly involved in the sensitivity process.
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Cloning and characterization of two K+ transporters of Debaryomyces hansenii.
Microbiology, 2007Co-Authors: Catarina Prista, José Ramos, Juan Carlos Gonzalez-hernandez, Maria C. Loureiro-diasAbstract:Two genes from the halotolerant yeast Debaryomyces hansenii were cloned, DhTRK1 and DhHAK1. These genes encode K+ transporters with sequence similarities to the TRK and HAK transporters from Debaryomyces occidentalis and Candida albicans. The DhHAK1p transporter was only expressed in K+-starved cells, as shown by Northern blot analysis. Both DhTRK1p and DhHAK1p were expressed in a trk1Δ trk2Δ mutant of Saccharomyces cerevisiae, unable to grow at low K+. This expression resulted in partial recovery of growth and ability to retain K+ at low concentrations. In liquid media, 0.5 M NaCl affected growth of these S. cerevisiae transformants as it does in D. hansenii, resulting in a much less deleterious effect than in wild-type S. cerevisiae. Kinetics of Rb+ uptake in the transformants suggest that DhTRK1p and DhHAK1p code for moderate-affinity K+ transporters exhibiting a sigmoid response against Rb+ concentration and presenting a deviation from classic Michaelis–Menten kinetics at low substrate concentrations. Rb+ uptake by the DhTRK1p transporter was stimulated by millimolar concentrations of Na+ at pH 4.5. The good performance of DhTRK1p in the presence of NaCl may be a key feature in the halotolerance of D. hansenii.
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Intracellular Na and K distribution in Debaryomyces hansenii. Cloning and expression in Saccharomyces cerevisiae of DhNHX1.
FEMS yeast research, 2007Co-Authors: Vera Montiel, José RamosAbstract:Debaryomyces hansenii is a salt-tolerant yeast that contains high amounts of internal Na+. Debaryomyces hansenii kept more sodium than Saccharomyces cerevisiae in both the cytoplasm and vacuole when grown under a variety of NaCl concentrations. These results indicate a higher tolerance of Debaryomyces to high internal Na+, and, in addition, suggest the existence of a transporter driving Na+ into the vacuole. Moreover, a gene encoding a Na+ (K+)/H+ antiporter from D. hansenii was cloned and sequenced. The gene, designated DhNHX1, exhibited significant homology with genes of the NHE/NHX family. DhNHX1 expression was induced neither at low pH nor by extracellular NaCl. A mutant of S. cerevisiae lacking its own Na+ transporters (ena1-4Δnha1Δnhx1Δ), when transformed with DhNHX1, partially recovered cation tolerance as well as the ability to accumulate Na+ and K+ into the vacuole. Our analysis provides evidence that DhNhx1p transports Na+ (and K+) into the vacuole and that it can play an important role in ion homeostasis and salt tolerance.
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Cloning and characterization of two K+ transporters of Debaryomyces hansenii.
Microbiology (Reading England), 2007Co-Authors: Catarina Prista, José Ramos, Juan Carlos Gonzalez-hernandez, Maria C. Loureiro-diasAbstract:Two genes from the halotolerant yeast Debaryomyces hansenii were cloned, DhTRK1 and DhHAK1. These genes encode K(+) transporters with sequence similarities to the TRK and HAK transporters from Debaryomyces occidentalis and Candida albicans. The DhHAK1p transporter was only expressed in K(+)-starved cells, as shown by Northern blot analysis. Both DhTRK1p and DhHAK1p were expressed in a trk1Delta trk2Delta mutant of Saccharomyces cerevisiae, unable to grow at low K(+). This expression resulted in partial recovery of growth and ability to retain K(+) at low concentrations. In liquid media, 0.5 M NaCl affected growth of these S. cerevisiae transformants as it does in D. hansenii, resulting in a much less deleterious effect than in wild-type S. cerevisiae. Kinetics of Rb(+) uptake in the transformants suggest that DhTRK1p and DhHAK1p code for moderate-affinity K(+) transporters exhibiting a sigmoid response against Rb(+) concentration and presenting a deviation from classic Michaelis-Menten kinetics at low substrate concentrations. Rb(+) uptake by the DhTRK1p transporter was stimulated by millimolar concentrations of Na(+) at pH 4.5. The good performance of DhTRK1p in the presence of NaCl may be a key feature in the halotolerance of D. hansenii.
María-isabel De Silóniz - One of the best experts on this subject based on the ideXlab platform.
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Development of species-specific primers for rapid identification of Debaryomyces hansenii.
International journal of food microbiology, 2014Co-Authors: Petra Wrent, José M. Peinado, Eva-maría Rivas, Elena Gil De Prado, María-isabel De SilónizAbstract:In this work, we developed a specific PCR assay for Debaryomyces hansenii strains that uses a putative homologous PAD1 region (729 bp) present in this yeast species as a target. The amplification of this sequence with the D. hansenii specific primer pair (DhPADF/DhPADR) was found to be a rapid, specific and an affordable method enabling identification of D. hansenii from other yeast strains. Primers were tested in almost 100 strains, 49 strains from Type Culture Collection belonging to the genus Debaryomyces and to other yeast species commonly found in foods or related genera. These primers were able to discriminate between closely related species of Debaryomyces, such as Debaryomyces fabryi and Debaryomyces subglobosus, with a 100% detection rate for D. hansenii. Also, the method was tested in 45 strains from different foods. Results confirmed the specificity of the PCR method and detected two earlier misidentifications of D. hansenii strains obtained by RFLP analysis of the 5.8S ITS rDNA region. Subsequently we confirmed by sequencing the D1/D2 domain of 26S rDNA that these strains belonged to D. fabryi. We call attention in this work to the fact that the RFLPs of the 5.8S ITS rDNA profiles of D. hansenii, D. fabryi and D. subglobosus are the same and this technique will thus lead to incorrect identifications.
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research article four new candida cretensis strains isolated from spanish fermented sausages chorizo taxonomic and phylogenetic implications
Fems Yeast Research, 2008Co-Authors: Manuel Quirós, José M. Peinado, Patricia Martorell, Amparo Querol, Eladio Barrio, María-isabel De SilónizAbstract:Four yeast strains were isolated from Spanish traditional fermented sausages (chorizo) spoiled by gas production. Using the classical identification procedures, they were identified as Debaryomyces hansenii. However, they fermented galactose and did not produce positive results in Debaryomyces differential medium (DDM), a growth medium highly specific for this species. Phylogenetic analysis showed identical sequences for the D1/D2 domain of the 26S rRNA gene and almost identical sequences for the 5.8S–ITS region with those of the recently described yeast species Candida cretensis. This result was confirmed by sequencing the gene encoding actin of the type and the new strains. Candida cretensis is a new species included in the so-called Candida kruisii clade that was described from a single strain, isolated from a decaying mushroom in Crete, Greece. The discovery of new strains of C. cretensis in fermented food expands its physiological and ecological diversity. With the description of these new strains isolated from food, three groups of strains can be distinguished within C. cretensis according to the restriction patterns of the intergenic spacer rRNA gene region and on the basis of some physiological properties that are of ecological relevance.
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four new candida cretensis strains isolated from spanish fermented sausages chorizo taxonomic and phylogenetic implications
Fems Yeast Research, 2008Co-Authors: Manuel Quirós, José M. Peinado, Patricia Martorell, Amparo Querol, Eladio Barrio, María-isabel De SilónizAbstract:Four yeast strains were isolated from Spanish traditional fermented sausages (chorizo) spoiled by gas production. Using the classical identification procedures, they were identified as Debaryomyces hansenii. However, they fermented galactose and did not produce positive results in Debaryomyces differential medium (DDM), a growth medium highly specific for this species. Phylogenetic analysis showed identical sequences for the D1/D2 domain of the 26S rRNA gene and almost identical sequences for the 5.8S-ITS region with those of the recently described yeast species Candida cretensis. This result was confirmed by sequencing the gene encoding actin of the type and the new strains. Candida cretensis is a new species included in the so-called Candida kruisii clade that was described from a single strain, isolated from a decaying mushroom in Crete, Greece. The discovery of new strains of C. cretensis in fermented food expands its physiological and ecological diversity. With the description of these new strains isolated from food, three groups of strains can be distinguished within C. cretensis according to the restriction patterns of the intergenic spacer rRNA gene region and on the basis of some physiological properties that are of ecological relevance.
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PCR-RFLP analysis of the IGS region of rDNA: a useful tool for the practical discrimination between species of the genus Debaryomyces
Antonie van Leeuwenhoek, 2006Co-Authors: Manuel Quirós, María-josé Valderrama, José M. Peinado, Patricia Martorell, Amparo Querol, María-isabel De SilónizAbstract:The amplification by PCR of the intergenic spacer region (IGS) of rDNA followed by restriction fragment length polymorphism (RFLP) analysis was evaluated as a potential method for discriminating the 16 species belonging to the genus Debaryomyces . The digestion of this region with some or all the enzymes used in this study ( Hap II, Hha I and Mbo I) produced species-specific patterns that permitted differentiation of the species in the genus. With the exception of Debaryomyces vanrijiae , the technique was also efficient for␣distinguishing the varieties in the species Debaryomyces hansenii (var. hansenii , var. fabryi ), Debaryomyces occidentalis (var. occidentalis , var. persoonii ) and Debaryomyces polymorphus (var. africanus , var. polymorphus ), respectively. PCR-RFLP analysis of the IGS region of rDNA is proposed as a clear and reproducible technique for the practical discrimination of species of the yeast genus Debaryomyces .
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A β-glucuronidase-based agar medium for the differential detection of the yeast Debaryomyces hansenii from foods
Journal of food protection, 2005Co-Authors: Manuel Quirós, María-josé Valderrama, María-isabel De Silóniz, Petra Wrent, José M. PeinadoAbstract:A selective and differential solid medium, Debaryomyces differential medium (DDM), was used for the isolation of Debaryomyces hansenii. This medium is formulated to allow detection of the β-glucuronidase enzyme using the chromogenic substrate magenta-glucuro.CHA (5Br-6Cl-3indolyl-β-d-glucuronide, cyclohexylammonium salt). Of the more than 120 micro-organisms tested, including yeasts, bacteria, and a filamentous fungus, only D. hansenii produced violet colonies, thus permitting its easy discrimination from other organisms. When quality assessment tests were performed, optimal productivity and selectivity were obtained for D. hansenii. The medium was also satisfactory when used to test naturally contaminated food products.
José M. Peinado - One of the best experts on this subject based on the ideXlab platform.
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Development of species-specific primers for rapid identification of Debaryomyces hansenii.
International journal of food microbiology, 2014Co-Authors: Petra Wrent, José M. Peinado, Eva-maría Rivas, Elena Gil De Prado, María-isabel De SilónizAbstract:In this work, we developed a specific PCR assay for Debaryomyces hansenii strains that uses a putative homologous PAD1 region (729 bp) present in this yeast species as a target. The amplification of this sequence with the D. hansenii specific primer pair (DhPADF/DhPADR) was found to be a rapid, specific and an affordable method enabling identification of D. hansenii from other yeast strains. Primers were tested in almost 100 strains, 49 strains from Type Culture Collection belonging to the genus Debaryomyces and to other yeast species commonly found in foods or related genera. These primers were able to discriminate between closely related species of Debaryomyces, such as Debaryomyces fabryi and Debaryomyces subglobosus, with a 100% detection rate for D. hansenii. Also, the method was tested in 45 strains from different foods. Results confirmed the specificity of the PCR method and detected two earlier misidentifications of D. hansenii strains obtained by RFLP analysis of the 5.8S ITS rDNA region. Subsequently we confirmed by sequencing the D1/D2 domain of 26S rDNA that these strains belonged to D. fabryi. We call attention in this work to the fact that the RFLPs of the 5.8S ITS rDNA profiles of D. hansenii, D. fabryi and D. subglobosus are the same and this technique will thus lead to incorrect identifications.
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research article four new candida cretensis strains isolated from spanish fermented sausages chorizo taxonomic and phylogenetic implications
Fems Yeast Research, 2008Co-Authors: Manuel Quirós, José M. Peinado, Patricia Martorell, Amparo Querol, Eladio Barrio, María-isabel De SilónizAbstract:Four yeast strains were isolated from Spanish traditional fermented sausages (chorizo) spoiled by gas production. Using the classical identification procedures, they were identified as Debaryomyces hansenii. However, they fermented galactose and did not produce positive results in Debaryomyces differential medium (DDM), a growth medium highly specific for this species. Phylogenetic analysis showed identical sequences for the D1/D2 domain of the 26S rRNA gene and almost identical sequences for the 5.8S–ITS region with those of the recently described yeast species Candida cretensis. This result was confirmed by sequencing the gene encoding actin of the type and the new strains. Candida cretensis is a new species included in the so-called Candida kruisii clade that was described from a single strain, isolated from a decaying mushroom in Crete, Greece. The discovery of new strains of C. cretensis in fermented food expands its physiological and ecological diversity. With the description of these new strains isolated from food, three groups of strains can be distinguished within C. cretensis according to the restriction patterns of the intergenic spacer rRNA gene region and on the basis of some physiological properties that are of ecological relevance.
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four new candida cretensis strains isolated from spanish fermented sausages chorizo taxonomic and phylogenetic implications
Fems Yeast Research, 2008Co-Authors: Manuel Quirós, José M. Peinado, Patricia Martorell, Amparo Querol, Eladio Barrio, María-isabel De SilónizAbstract:Four yeast strains were isolated from Spanish traditional fermented sausages (chorizo) spoiled by gas production. Using the classical identification procedures, they were identified as Debaryomyces hansenii. However, they fermented galactose and did not produce positive results in Debaryomyces differential medium (DDM), a growth medium highly specific for this species. Phylogenetic analysis showed identical sequences for the D1/D2 domain of the 26S rRNA gene and almost identical sequences for the 5.8S-ITS region with those of the recently described yeast species Candida cretensis. This result was confirmed by sequencing the gene encoding actin of the type and the new strains. Candida cretensis is a new species included in the so-called Candida kruisii clade that was described from a single strain, isolated from a decaying mushroom in Crete, Greece. The discovery of new strains of C. cretensis in fermented food expands its physiological and ecological diversity. With the description of these new strains isolated from food, three groups of strains can be distinguished within C. cretensis according to the restriction patterns of the intergenic spacer rRNA gene region and on the basis of some physiological properties that are of ecological relevance.
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PCR-RFLP analysis of the IGS region of rDNA: a useful tool for the practical discrimination between species of the genus Debaryomyces
Antonie van Leeuwenhoek, 2006Co-Authors: Manuel Quirós, María-josé Valderrama, José M. Peinado, Patricia Martorell, Amparo Querol, María-isabel De SilónizAbstract:The amplification by PCR of the intergenic spacer region (IGS) of rDNA followed by restriction fragment length polymorphism (RFLP) analysis was evaluated as a potential method for discriminating the 16 species belonging to the genus Debaryomyces . The digestion of this region with some or all the enzymes used in this study ( Hap II, Hha I and Mbo I) produced species-specific patterns that permitted differentiation of the species in the genus. With the exception of Debaryomyces vanrijiae , the technique was also efficient for␣distinguishing the varieties in the species Debaryomyces hansenii (var. hansenii , var. fabryi ), Debaryomyces occidentalis (var. occidentalis , var. persoonii ) and Debaryomyces polymorphus (var. africanus , var. polymorphus ), respectively. PCR-RFLP analysis of the IGS region of rDNA is proposed as a clear and reproducible technique for the practical discrimination of species of the yeast genus Debaryomyces .
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A β-glucuronidase-based agar medium for the differential detection of the yeast Debaryomyces hansenii from foods
Journal of food protection, 2005Co-Authors: Manuel Quirós, María-josé Valderrama, María-isabel De Silóniz, Petra Wrent, José M. PeinadoAbstract:A selective and differential solid medium, Debaryomyces differential medium (DDM), was used for the isolation of Debaryomyces hansenii. This medium is formulated to allow detection of the β-glucuronidase enzyme using the chromogenic substrate magenta-glucuro.CHA (5Br-6Cl-3indolyl-β-d-glucuronide, cyclohexylammonium salt). Of the more than 120 micro-organisms tested, including yeasts, bacteria, and a filamentous fungus, only D. hansenii produced violet colonies, thus permitting its easy discrimination from other organisms. When quality assessment tests were performed, optimal productivity and selectivity were obtained for D. hansenii. The medium was also satisfactory when used to test naturally contaminated food products.
Manuel Quirós - One of the best experts on this subject based on the ideXlab platform.
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research article four new candida cretensis strains isolated from spanish fermented sausages chorizo taxonomic and phylogenetic implications
Fems Yeast Research, 2008Co-Authors: Manuel Quirós, José M. Peinado, Patricia Martorell, Amparo Querol, Eladio Barrio, María-isabel De SilónizAbstract:Four yeast strains were isolated from Spanish traditional fermented sausages (chorizo) spoiled by gas production. Using the classical identification procedures, they were identified as Debaryomyces hansenii. However, they fermented galactose and did not produce positive results in Debaryomyces differential medium (DDM), a growth medium highly specific for this species. Phylogenetic analysis showed identical sequences for the D1/D2 domain of the 26S rRNA gene and almost identical sequences for the 5.8S–ITS region with those of the recently described yeast species Candida cretensis. This result was confirmed by sequencing the gene encoding actin of the type and the new strains. Candida cretensis is a new species included in the so-called Candida kruisii clade that was described from a single strain, isolated from a decaying mushroom in Crete, Greece. The discovery of new strains of C. cretensis in fermented food expands its physiological and ecological diversity. With the description of these new strains isolated from food, three groups of strains can be distinguished within C. cretensis according to the restriction patterns of the intergenic spacer rRNA gene region and on the basis of some physiological properties that are of ecological relevance.
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four new candida cretensis strains isolated from spanish fermented sausages chorizo taxonomic and phylogenetic implications
Fems Yeast Research, 2008Co-Authors: Manuel Quirós, José M. Peinado, Patricia Martorell, Amparo Querol, Eladio Barrio, María-isabel De SilónizAbstract:Four yeast strains were isolated from Spanish traditional fermented sausages (chorizo) spoiled by gas production. Using the classical identification procedures, they were identified as Debaryomyces hansenii. However, they fermented galactose and did not produce positive results in Debaryomyces differential medium (DDM), a growth medium highly specific for this species. Phylogenetic analysis showed identical sequences for the D1/D2 domain of the 26S rRNA gene and almost identical sequences for the 5.8S-ITS region with those of the recently described yeast species Candida cretensis. This result was confirmed by sequencing the gene encoding actin of the type and the new strains. Candida cretensis is a new species included in the so-called Candida kruisii clade that was described from a single strain, isolated from a decaying mushroom in Crete, Greece. The discovery of new strains of C. cretensis in fermented food expands its physiological and ecological diversity. With the description of these new strains isolated from food, three groups of strains can be distinguished within C. cretensis according to the restriction patterns of the intergenic spacer rRNA gene region and on the basis of some physiological properties that are of ecological relevance.
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PCR-RFLP analysis of the IGS region of rDNA: a useful tool for the practical discrimination between species of the genus Debaryomyces
Antonie van Leeuwenhoek, 2006Co-Authors: Manuel Quirós, María-josé Valderrama, José M. Peinado, Patricia Martorell, Amparo Querol, María-isabel De SilónizAbstract:The amplification by PCR of the intergenic spacer region (IGS) of rDNA followed by restriction fragment length polymorphism (RFLP) analysis was evaluated as a potential method for discriminating the 16 species belonging to the genus Debaryomyces . The digestion of this region with some or all the enzymes used in this study ( Hap II, Hha I and Mbo I) produced species-specific patterns that permitted differentiation of the species in the genus. With the exception of Debaryomyces vanrijiae , the technique was also efficient for␣distinguishing the varieties in the species Debaryomyces hansenii (var. hansenii , var. fabryi ), Debaryomyces occidentalis (var. occidentalis , var. persoonii ) and Debaryomyces polymorphus (var. africanus , var. polymorphus ), respectively. PCR-RFLP analysis of the IGS region of rDNA is proposed as a clear and reproducible technique for the practical discrimination of species of the yeast genus Debaryomyces .
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A β-glucuronidase-based agar medium for the differential detection of the yeast Debaryomyces hansenii from foods
Journal of food protection, 2005Co-Authors: Manuel Quirós, María-josé Valderrama, María-isabel De Silóniz, Petra Wrent, José M. PeinadoAbstract:A selective and differential solid medium, Debaryomyces differential medium (DDM), was used for the isolation of Debaryomyces hansenii. This medium is formulated to allow detection of the β-glucuronidase enzyme using the chromogenic substrate magenta-glucuro.CHA (5Br-6Cl-3indolyl-β-d-glucuronide, cyclohexylammonium salt). Of the more than 120 micro-organisms tested, including yeasts, bacteria, and a filamentous fungus, only D. hansenii produced violet colonies, thus permitting its easy discrimination from other organisms. When quality assessment tests were performed, optimal productivity and selectivity were obtained for D. hansenii. The medium was also satisfactory when used to test naturally contaminated food products.
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Differential detection of Debaryomyces hansenii isolated from intermediate-moisture foods by PCR-RFLP of the IGS region of rDNA
Fems Yeast Research, 2005Co-Authors: Patricia Barrero Romero, María-josé Valderrama, Belén Patiño, Manuel Quirós, María-teresa González-jaén, María-isabel De Silóniz, José M. PeinadoAbstract:The amplification by PCR of the Intergenic Spacer region (IGS) of rDNA followed by Restriction Fragment Length Polymorphism (RFLP) analysis was evaluated as a potential method for the identification of Debaryomyces hansenii among other yeast species that frequently contaminate Intermediate-Moisture Foods (IMFs). For a first rapid differentiation at the species level, the determination of the IGS-PCR fragment size was found to be a useful approach. The digestion of this region with the enzymes HhaI, HapII and MboI resulted in specific patterns that permit the identification of D. hansenii among other yeast species. This method also permitted the discrimination between the D. hansenii varieties (var. hansenii and var. fabryi) as well as the differentiation of D. hansenii from other species of the genus, such as Debaryomyces pseudopolymorphus or Debaryomyces polymorphus var. polymorphus. The IGS-PCR RFLP method was assayed for the differential detection of D. hansenii in contaminated or spoiled IMF products and compared with traditional identification procedures, resulting in a 100% detection rate for D. hansenii.
Lene Jespersen - One of the best experts on this subject based on the ideXlab platform.
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alcohol based quorum sensing plays a role in adhesion and sliding motility of the yeast Debaryomyces hansenii
Fems Yeast Research, 2011Co-Authors: Klaus Gori, Peter Boldsen Knudsen, Kristian Fog Nielsen, Nils Arneborg, Lene JespersenAbstract:The yeast Debaryomyces hansenii was investigated for its production of alcohol-based quorum sensing (QS) molecules including the aromatic alcohols phenylethanol, tyrosol, tryptophol and the aliphatic alcohol farnesol. Debaryomyces hansenii produced phenylethanol and tyrosol, which were primarily detected from the end of exponential phase indicating that they are potential QS molecules in D. hansenii as previously shown for other yeast species. Yields of phenylethanol and tyrosol produced by D. hansenii were, however, lower than those produced by Candida albicans and Saccharomyces cerevisiae and varied with growth conditions such as the availability of aromatic amino acids, ammonium sulphate, NaCl, pH and temperature. Tryptophol was only produced in the presence of tryptophane, whereas farnesol in general was not detectable. Especially, the type strain of D. hansenii (CBS767) had good adhesion and sliding motility abilities, which seemed to be related to a higher hydrophobicity of the cell surface of D. hansenii (CBS767) rather than the ability to form pseudomycelium. Addition of phenylethanol, tyrosol, tryptophol and farnesol was found to influence both adhesion and sliding motility of D. hansenii.
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Alcohol‐based quorum sensing plays a role in adhesion and sliding motility of the yeast Debaryomyces hansenii
FEMS yeast research, 2011Co-Authors: Klaus Gori, Peter Boldsen Knudsen, Kristian Fog Nielsen, Nils Arneborg, Lene JespersenAbstract:The yeast Debaryomyces hansenii was investigated for its production of alcohol-based quorum sensing (QS) molecules including the aromatic alcohols phenylethanol, tyrosol, tryptophol and the aliphatic alcohol farnesol. Debaryomyces hansenii produced phenylethanol and tyrosol, which were primarily detected from the end of exponential phase indicating that they are potential QS molecules in D. hansenii as previously shown for other yeast species. Yields of phenylethanol and tyrosol produced by D. hansenii were, however, lower than those produced by Candida albicans and Saccharomyces cerevisiae and varied with growth conditions such as the availability of aromatic amino acids, ammonium sulphate, NaCl, pH and temperature. Tryptophol was only produced in the presence of tryptophane, whereas farnesol in general was not detectable. Especially, the type strain of D. hansenii (CBS767) had good adhesion and sliding motility abilities, which seemed to be related to a higher hydrophobicity of the cell surface of D. hansenii (CBS767) rather than the ability to form pseudomycelium. Addition of phenylethanol, tyrosol, tryptophol and farnesol was found to influence both adhesion and sliding motility of D. hansenii.
