Screening of reducing agents for anaerobic growth of Candida albicans SC5314.

This study aimed to evaluate the influence of different redox potentials (Eh) on cell growth, whole-cell protein profile and cell surface hydrophobicity (CSH) of Candida albicans SC5314. The yeast was grown in YNB broth enriched with reducing (158mM sodium sulfite, 4mM sodium sulfite, 2.5mM sodium metabisulfite, 1.3mM 2-mercaptoethanol, 5.5mM thioglycolic acid, and 3.2mM l-cysteine hydrochloride) and oxidizing agents (15mM ammonium persulfate and 80mM potassium ferricyanide) and incubated in normoxic and anoxic atmospheres at 37°C, for 48h. Pre- and post-incubation Eh values were determined and cytoplasm proteins were extracted. Proteins were parted by SDS-PAGE and their profiles were compared. 3.2mM l-cysteine and 1.3mM 2-mercaptoethanol promoted and maintained negative Eh values during incubation. No differences were detected among SDS-PAGE profiles. CSH differences only were observed with 4mM sodium sulfite and 3.2mM l-cysteine. Results showed that 3.2mM l-cysteine is a reducing agent that allows maintenance of negative Eh in both anoxic and normoxic conditions and it seems not to interfere in the global expression of plasmatic proteins.

Proposal of protocols using D-glutamine to optimize the 2,3-bis(2-methoxy-4-nitro-5-sulfophenly)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) assay for indirect estimation of microbial loads in biofilms of medical importance.

Due to technical problems, biofilm biomasses are difficult to be precisely determined. One reliable strategy is based on the colorimetry of formazan compounds derived from tetrazolium salt reduction. XTT presents some desirable properties that make the biofilm measurements easier. However, cells entrapped within the extracellular matrixes normally do not metabolize the tetrazolium equally, leading to underestimation of cell contents. This study evaluated the effectiveness of D-glutamine, a plerotic substrate of tricarboxilic acid cycle (TAC), as inducer of XTT reduction. The metabolic activities of aerobic and anaerobic 48 h-old monospecific biofilms of Pseudomonas aeruginosa ATCC®27853™, Klebsiella pneumoniae ATCC®13883™, Staphylococcus epidermidis ATCC®12228™, Streptococcus mutans ATCC®25175™, and Candida albicans SC5314 were evaluated. Results showed that D-glutamine 50 mM (for P. aeruginosa, K. pneumoniae, and S. epidermidis) and 25 mM (for S. mutans and C. albicans) may enhance the detection of soluble formazan in a significant manner, what becomes the XTT reduction assay more robust.

Mutacin production in Streptococcus mutans genotypes isolated from caries-affected and caries-free individuals.

Relationships between genetic diversity and mutacin production in Streptococcus mutans were evaluated in 319 clinical isolates from eight caries-affected and eight caries-free individuals. The isolates were submitted to mutacin typing and AP-PCR (arbitrarily primed polymerase chain reaction) assay. The mutacin production was detected for 12 Streptococcus sp. indicator strains. Results showed significant variations in the mutacin production profiles and the inhibitory spectra of both groups. A possible association was seen between mutacin activity and the distinct patterns of Streptococcus sp. colonization in the two groups. Genotyping by AP-PCR using the primers OPA-02 and OPA-13 revealed 101 distinct genotypes against 48 phenotypes identified by mutacin typing. No correlation was observed between the inhibitory spectra of mutacin and genotypic similarities based on AP-PCR analyses. According to our results, strains of the same S. mutans genotype showed different mutacin profiles, suggesting a high degree of interstrain diversity. In conclusion, mutacin production seems to be of clinical importance in the colonization of S. mutans and is highly diversified in the S. mutans species.

Oral Candida albicans and Candida dubliniensis differentiation by multilocus enzyme electrophoresis and sodium dodecylsulphate-polyacrylamide gel electrophoresis.

Five oral strains of Candida albicans and five C. dubliniensis, as well as their respective type-strains, were analyzed by multilocus enzyme electrophoresis (MLEE) and sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE). After electrophoreses and numerical analyses, we obtained two distinct species-specific taxa, which may justify the use of MLEE and SDS-PAGE as reliable methods for differentiation and complementary identification of C. dubliniensis.

DiferenciaciOn de Candida albicans y Candida dubliniensis por técnicas de electroforesis en geles de almidón y de poliacrilamida / Oral Candida albicans and Candida dubliniensis differentiatioin by multilocus enzyme electrophoresis and sodium dodecylsulphate-polyacrylamide gel electrophoresis

Cinco cepas de Candida albicans y otras cinco de C. dubliniensis así como sus cepas-patrón fueron evaluadas mediante el empleo de técnicas de electroforesis en geles de almidón y de poliacrilamida. Después de las electroforesis y evaluación numérica, se obtuvieron dos taxa muy distintos, que pueden justificar el uso de MLEE y SDS-PAGE como métodos confiables para la diferenciación e identificación complementaria de C.dubliniensis. (AU)

DiferenciaciÓn de Candida albicans y Candida dubliniensis por técnicas de electroforesis en geles de almidón y de poliacrilamida / Oral Candida albicans and Candida dubliniensis differentiatioin by multilocus enzyme electrophoresis and sodium dodecylsulphate-polyacrylamide gel electrophoresis

Cinco cepas de Candida albicans y otras cinco de C. dubliniensis así como sus cepas-patrón fueron evaluadas mediante el empleo de técnicas de electroforesis en geles de almidón y de poliacrilamida. Después de las electroforesis y evaluación numérica, se obtuvieron dos taxa muy distintos, que pueden justificar el uso de MLEE y SDS-PAGE como métodos confiables para la diferenciación e identificación complementaria de C.dubliniensis.

Oral Candida albicans and Candida dubliniensis differentiation by multilocus enzyme electrophoresis and sodium dodecylsulphate-polyacrylamide gel electrophoresis.

Five oral strains of Candida albicans and five C. dubliniensis, as well as their respective type-strains, were analyzed by multilocus enzyme electrophoresis (MLEE) and sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE). After electrophoreses and numerical analyses, we obtained two distinct species-specific taxa, which may justify the use of MLEE and SDS-PAGE as reliable methods for differentiation and complementary identification of C. dubliniensis.

Analysis of parity between protein-based electrophoretic methods for the characterization of oral Candida species

Electrophoretic studies of multilocus-enzymes (MLEE) and whole-cell protein (SDS-PAGE) were carried out in order to evaluate the parity between different methods for the characterization of five Candida species commonly isolated from oral cavity of humans by numerical taxonomy methods. The obtained data revealed that sodium dodecyl sulfate polyacrylamide gel electrophoresis is more efficient in grouping strains in their respective species while MLEE has much limited resolution in organizing all strains in their respective species-specific clusters. MLEE technique must be regarded for surveys in which just one species of Candida is involved

Analysis of parity between protein-based electrophoretic methods for the characterization of oral Candida species.

Electrophoretic studies of multilocus-enzymes (MLEE) and whole-cell protein (SDS-PAGE) were carried out in order to evaluate the parity between different methods for the characterization of five Candida species commonly isolated from oral cavity of humans by numerical taxonomy methods. The obtained data revealed that sodium dodecyl sulfate polyacrylamide gel electrophoresis is more efficient in grouping strains in their respective species while MLEE has much limited resolution in organizing all strains in their respective species-specific clusters. MLEE technique must be regarded for surveys in which just one species of Candida is involved.

Criteria for Candida albicans numerical analysis based on electrophoretic protein patterns.

Even in normalized gels, some problems with the choice and position of protein bands always have hindered the processing of electrophoretic data. We have developed a way to establish which criterion best fits the necessities in order to maximize the similarity indexes for numerical analysis. Some repetitions of a Candida albicans strain were carried out in eleven different gels. After staining, the bands were scored in numbers within ranges of +/- n values with increases of one quarter steps (+/- 0.25 kDa, +/- 0.5 kDa, +/- 0.75 kDa, +/- 1.0 kDa, +/- 1.25 kDa) that will limit the possibility of variation for the same bands that will appear on the repetitions. Using this criterion, we have determined that values scored within +/- 1.25 kDa could optimize the minimum limiting value of similarity in different dendrograms built.

Criteria for Candida albicans numerical analysis based on electrophoretic protein patterns

Even in normalized gels, some problems with the choice and position of protein bands always have hindered the processing of electrophoretic data. We have developed a way to establish which criterion best fits the necessities in order to maximize the similarity indexes for numerical analysis. Some repetitions of a Candida albicans strain were carried out in eleven different gels. After staining, the bands were scored in numbers within ranges of +/- n values with increases of one quarter steps (+/- 0.25 kDa, +/- 0.5 kDa, +/- 0.75 kDa, +/- 1.0 kDa, +/- 1.25 kDa) that will limit the possibility of variation for the same bands that will appear on the repetitions. Using this criterion, we have determined that values scored within +/- 1.25 kDa could optimize the minimum limiting value of similarity in different dendrograms built.(AU)

Criteria for Candida albicans numerical analysis based on electrophoretic protein patterns

Even in normalized gels, some problems with the choice and position of protein bands always have hindered the processing of electrophoretic data. We have developed a way to establish which criterion best fits the necessities in order to maximize the similarity indexes for numerical analysis. Some repetitions of a Candida albicans strain were carried out in eleven different gels. After staining, the bands were scored in numbers within ranges of +/- n values with increases of one quarter steps (+/- 0.25 kDa, +/- 0.5 kDa, +/- 0.75 kDa, +/- 1.0 kDa, +/- 1.25 kDa) that will limit the possibility of variation for the same bands that will appear on the repetitions. Using this criterion, we have determined that values scored within +/- 1.25 kDa could optimize the minimum limiting value of similarity in different dendrograms built.

Grouping oral Candida species by multilocus enzyme electrophoresis.

Multilocus enzyme electrophoresis (MLEE) and numerical taxonomic methods were used to establish the degrees of relatedness among five Candida species commonly isolated from humans oral cavities. Of twenty enzymic systems assayed, five showed no enzymic activity (aspartate dehydrogenase, mannitol dehydrogenase, sorbitol dehydrogenase, glucosyl transferase and alpha-amylase). The obtained data revealed that some of these enzymes are capable of distinguishing strains of different species, but most of them could not organize all strains in their respective species-specific clusters. Numerical classification based on MLEE polymorphism must be regarded for surveys involving just one Candida species.

Clonal variability among oral Candida albicans assessed by allozyme electrophoresis analysis.

A total of 49 Candida albicans strains were isolated from the saliva of 11 healthy children in Piracicaba, Brazil and were analyzed according to their alloenzymatic patterns. Among eight loci assayed, seven were polymorphic and allowed to determine allelic and genotype frequencies, in order to establish the genetic variables for this fungal population. Some children showed just one genetic type, whereas other harbored two or more clones of such yeast, in a multiclonal manner of colonization by C. albicans.

Criteria for Candida albicans numerical analysis based on electrophoretic protein patterns.

Even in normalized gels, some problems with the choice and position of protein bands always have hindered the processing of electrophoretic data. We have developed a way to establish which criterion best fits the necessities in order to maximize the similarity indexes for numerical analysis. Some repetitions of a Candida albicans strain were carried out in eleven different gels. After staining, the bands were scored in numbers within ranges of +/- n values with increases of one quarter steps (+/- 0.25 kDa, +/- 0.5 kDa, +/- 0.75 kDa, +/- 1.0 kDa, +/- 1.25 kDa) that will limit the possibility of variation for the same bands that will appear on the repetitions. Using this criterion, we have determined that values scored within +/- 1.25 kDa could optimize the minimum limiting value of similarity in different dendrograms built.

Evaluation of different dehydrogenases to recognize Candida species commonly isolated from human oral cavities

Electrophoresis of some dehydrogenases were carried out in order to establish relatedness degrees among five Candida species commonly isolated from oral cavity of humans, by numerical taxonomy methods. The obtained data revealed that some dehydrogenases are capable of distinguishing strains of different species, but most of these enzymes could not organize all strains in their respective clusters. Numerical classifications based on dehydrogenase polymorphism must be considered for surveys involving just one species of yeast genus, where this resource had already shown to be useful.(AU)

Evaluation of different dehydrogenases to recognize Candida species commonly isolated from human oral cavities

Electrophoresis of some dehydrogenases were carried out in order to establish relatedness degrees among five Candida species commonly isolated from oral cavity of humans, by numerical taxonomy methods. The obtained data revealed that some dehydrogenases are capable of distinguishing strains of different species, but most of these enzymes could not organize all strains in their respective clusters. Numerical classifications based on dehydrogenase polymorphism must be considered for surveys involving just one species of yeast genus, where this resource had already shown to be useful.

Evaluation of different dehydrogenases to recognize Candida species commonly isolated from human oral cavities.

Electrophoresis of some dehydrogenases were carried out in order to establish relatedness degrees among five Candida species commonly isolated from oral cavity of humans, by numerical taxonomy methods. The obtained data revealed that some dehydrogenases are capable of distinguishing strains of different species, but most of these enzymes could not organize all strains in their respective clusters. Numerical classifications based on dehydrogenase polymorphism must be considered for surveys involving just one species of yeast genus, where this resource had already shown to be useful.