RESUMO
The main polysaccharide of the gel present in the leaves of or Aloe vera Burm.F., (Aloe barbadensis Miller) a xerophytic crassulacean acid metabolism (CAM) plant, is an acetylated glucomannan named acemannan. This polysaccharide is responsible for the succulence of the plant, helping it to retain water. In this study we determined using polysaccharide analysis by carbohydrate gel electrophoresis (PACE) that the acemannan is a glucomannan without galactose side branches. We also investigated the expression of the gene responsible for acemannan backbone synthesis, encoding a glucomannan mannosyltransferase (GMMT, EC 2.4.1.32), since there are no previous reports on GMMT expression under water stress in general and specifically in Aloe vera. It was found by in silico analyses that the GMMT gene belongs to the cellulose synthase-like A type-9 (CSLA9) subfamily. Using RT-qPCR it was found that the expression of GMMT increased significantly in Aloe vera plants subjected to water stress. This expression correlates with an increase of endogenous ABA levels, suggesting that the gene expression could be regulated by ABA. To corroborate this hypothesis, exogenous ABA was applied to non-water-stressed plants, resulting in a significant increase of GMMT expression after 48â¯h of ABA treatment.
Assuntos
Ácido Abscísico/farmacologia , Aloe/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Mananas/metabolismo , Metiltransferases/genética , Estresse Fisiológico , Água/metabolismo , Aloe/enzimologia , Aloe/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Domínio Catalítico , DNA Complementar/genética , Secas , Eletroforese em Gel de Amido/métodos , Cromatografia Gasosa-Espectrometria de Massas , Metiltransferases/química , Metiltransferases/metabolismo , Homologia de Sequência de AminoácidosRESUMO
Starch gel electrophoresis was used for examining the transferrin gene locus (Tf) and two esterase gene loci (Est-1 and Est-D1) of a pirarucu (Arapaima gigas) population sample collected from Santa Cruz Lake, Tefé River, Amazonas, Brazil. The Tf locus was tentatively classified as being polymorphic, showing two double-banded patterns (Tf(12) and Tf(22)) of the three theoretically expected ones (Tf(11), Tf(12) and Tf(22)), presumably controlled by two co-dominant alleles, Tf(1) and Tf(2). The monotony detected in pirarucu Tf locus genotypes showing a very high proportion of the double-banded heterozygote pattern Tf(12) (95% of the sampled individuals) may indicate the possibility of their having come from representatives of the same brood begotten by a pair of fish, where a single-banded Tf(11) homozygote pattern male would have crossed with a single-banded Tf(22) homozygote pattern female, or vice versa. One zone of electrophoretic activity was detected in esterase, presumably controlled by a monomorphic Est-1 locus with the fixed allele Est-1(1) where all individuals showed the single-banded Est-1(11) homozygote pattern. Esterase-D also displayed one zone of electrophoretic activity, presumably controlled by a monomorphic Est-D1 locus with a fixed allele Est-D1(1) where all individuals revealed the single-banded Est-D1(11) genotype pattern. The monotony comprised by single-banded genotype patterns in both esterase systems tested may also indicate the possibility of the individuals from the sample examined having come from representatives of the same brood begotten by a pair of fish with both the male and female having the same genotypes.
Assuntos
Esterases/genética , Proteínas de Peixes/genética , Peixes/genética , Transferrina/genética , Alelos , Animais , Brasil , Eletroforese em Gel de Amido/métodos , Feminino , Genótipo , Geografia , Masculino , Polimorfismo GenéticoRESUMO
Starch gel electrophoresis was used for examining the transferrin gene locus (Tf) and two esterase gene loci (Est-1 and Est-D1) of a pirarucu (Arapaima gigas) population sample collected from Santa Cruz Lake, Tefé River, Amazonas, Brazil. The Tf locus was tentatively classified as being polymorphic, showing two double-banded patterns (Tf 12 and Tf 22) of the three theoretically expected ones (Tf 11, Tf 12 and Tf 22), presumably controlled by two co-dominant alleles, Tf 1 and Tf 2. The monotony detected in pirarucu Tf locus genotypes showing a very high proportion of the double-banded heterozygote pattern Tf 12 (95% of the sampled individuals) may indicate the possibility of their having come from representatives of the same brood begotten by a pair of fish, where a single-banded Tf 11 homozygote pattern male would have crossed with a single-banded Tf 22 homozygote pattern female, or vice versa. One zone of electrophoretic activity was detected in esterase, presumably controlled by a monomorphic Est-1 locus with the fixed allele Est-11 where all individuals showed the single-banded Est-111 homozygote pattern. Esterase-D also displayed one zone of electrophoretic activity, presumably controlled by a monomorphic Est-D1 locus with a fixed allele Est-D11 where all individuals revealed the single-banded Est-D111 genotype pattern. The monotony comprised by single-banded genotype patterns in both esterase systems tested may also indicate the possibility of the individuals from the sample examined having come from representatives of the same brood begotten by a pair of fish with both the male and female having the same genotypes.
Assuntos
Animais , Masculino , Feminino , Esterases/genética , Peixes/genética , Proteínas de Peixes/genética , Transferrina/genética , Alelos , Brasil , Eletroforese em Gel de Amido/métodos , Genótipo , Geografia , Polimorfismo GenéticoRESUMO
Descreveram-se os marcadores isoenzimáticos e estimou-se a variabilidade genética de 20 subpopulações brasileiras de escargots (Helix aspersa). O estudo dos oito locos foi feito por eletroforese em gel de amido, em amostras com 30 indivíduos cada, obtidas em criatórios dos estados de Santa Catarina, São Paulo e Rio de Janeiro (uma, duas e 17 amostras, respectivamente). Observou-se polimorfismo nos locos das enzimas LAP, 6-PGD, PEP 2, PEP 1 e MDH, com três alelos nos três primeiros locos e dois nos demais. Os locos da ME, da SOD e da PGI apresentaram-se monomórficos. As freqüências gênicas de sete amostras ajustaram-se ao modelo de Hardy-Weinberg (P<0,05), e as de outras seis amostras ajustaram-se ao modelo de Wright (P<0,05), indicando que elas estão submetidas a diferentes regimes reprodutivos. Os desvios da panmixia para toda a população (F IT ) e dentro das subpopulações (F IS) não foram significativos (P³0,05). O desvio entre as subpopulações (F ST=0,0485) foi significativo (P<0,05) e apontou pequena diferenciação entre elas. As estimativas de diversidade total (Ht), entre subpopulações (Dst) e dentro das subpopulações (Hs), indicaram que a diversidade genética é reduzida e sua maior parte encontra-se dentro das subpopulações, sugerindo uma base genética estreita para essa população. As distâncias genéticas também foram pequenas, não permitindo a construção de um dendrograma.
Assuntos
Eletroforese em Gel de Amido/métodos , Variação Genética , Caracois Helix , Isoenzimas/análiseRESUMO
Descreveram-se os marcadores isoenzimáticos e estimou-se a variabilidade genética de 20 subpopulações brasileiras de escargots (Helix aspersa). O estudo dos oito locos foi feito por eletroforese em gel de amido, em amostras com 30 indivíduos cada, obtidas em criatórios dos estados de Santa Catarina, São Paulo e Rio de Janeiro (uma, duas e 17 amostras, respectivamente). Observou-se polimorfismo nos locos das enzimas LAP, 6-PGD, PEP 2, PEP 1 e MDH, com três alelos nos três primeiros locos e dois nos demais. Os locos da ME, da SOD e da PGI apresentaram-se monomórficos. As freqüências gênicas de sete amostras ajustaram-se ao modelo de Hardy-Weinberg (P<0,05), e as de outras seis amostras ajustaram-se ao modelo de Wright (P<0,05), indicando que elas estão submetidas a diferentes regimes reprodutivos. Os desvios da panmixia para toda a população (F IT ) e dentro das subpopulações (F IS) não foram significativos (P³0,05). O desvio entre as subpopulações (F ST=0,0485) foi significativo (P<0,05) e apontou pequena diferenciação entre elas. As estimativas de diversidade total (Ht), entre subpopulações (Dst) e dentro das subpopulações (Hs), indicaram que a diversidade genética é reduzida e sua maior parte encontra-se dentro das subpopulações, sugerindo uma base genética estreita para essa população. As distâncias genéticas também foram pequenas, não permitindo a construção de um dendrograma.(AU)
In order to assess genetic variability in subpopulations of Helix aspersa, eight isoenzyme loci in 30 individuals in each of 20 subpopulations, obtained from breeders in Santa Catarina (1), São Paulo(2) and Rio de Janeiro (17) states of Brazil, were examined. Polymorphic loci included LAP, 6-PGD, PEP 2, PEP 1 and MDH, with three alelles at each of the first three loci and two at each of the others. The ME, SOD and PGI loci were monomorphic. Gene frequencies in 7 of 20 subpopulations were consistent with the Hardy-Wienberg equilibrium (P<0.05), and 6 were consistent with Wright model, indicating that these subpopulations did not meet requirements for genotypic equilibrium to be achieved. Despite the fact that some F values were high, FIS and FIT were not significantly different from zero (P³0.05). Although small, the FST value (0.0485) was significant, suggesting small differences among populations. Most of the low genetic variation at isoenzyme loci was observed within subpopulations rather than among subpopulations, suggesting a small genetic basis for these samples. Estimated genetic distances among pairs of subpopulations also were low.(AU)
Assuntos
Variação Genética , Eletroforese em Gel de Amido/métodos , Isoenzimas/análise , Caracois HelixRESUMO
The typing of C. albicans by MLEE (multilocus enzyme electrophoresis) is dependent on the interpretation of enzyme electrophoretic patterns, and the study of the epidemiological relationships of these yeasts can be conducted by cluster analysis. Therefore, the aims of the present study were to first determine the discriminatory power of genetic interpretation (deduction of the allelic composition of diploid organisms) and numerical interpretation (mere determination of the presence and absence of bands) of MLEE patterns, and then to determine the concordance (Pearson product-moment correlation coefficient) and similarity (Jaccard similarity coefficient) of the groups of strains generated by three cluster analysis models, and the discriminatory power of such models as well [model A: genetic interpretation, genetic distance matrix of Nei (d(ij)) and UPGMA dendrogram; model B: genetic interpretation, Dice similarity matrix (S(D1)) and UPGMA dendrogram; model C: numerical interpretation, Dice similarity matrix (S(D2)) and UPGMA dendrogram]. MLEE was found to be a powerful and reliable tool for the typing of C. albicans due to its high discriminatory power (>0.9). Discriminatory power indicated that numerical interpretation is a method capable of discriminating a greater number of strains (47 versus 43 subtypes), but also pointed to model B as a method capable of providing a greater number of groups, suggesting its use for the typing of C. albicans by MLEE and cluster analysis. Very good agreement was only observed between the elements of the matrices S(D1) and S(D2), but a large majority of the groups generated in the three UPGMA dendrograms showed similarity S(J) between 4.8% and 75%, suggesting disparities in the conclusions obtained by the cluster assays.
Assuntos
Candida albicans/classificação , Eletroforese em Gel de Amido/métodos , Alelos , Candida albicans/enzimologia , Candida albicans/genética , Criança , Análise por Conglomerados , Variação Genética , Humanos , Boca/microbiologia , FilogeniaRESUMO
The genetic diversity of 47 clinical and reference strains of Candida glabrata from several geographical origins and diverse clinical disorders, with different antifungal susceptibilities, as well as their genetic relationships were studied through multilocus enzyme electrophoresis (MLEE) and randomly amplified polymorphic DNA (RAPD) techniques. The genetic diversity estimated for 11 MLEE loci measured as average heterozygosity (h) was 0.055. A high level of genetic relatedness among isolates was established by cluster analysis. Forty-nine RAPD markers were analyzed, and the average genetic diversity among isolates, estimated by Shannon's index (Ho), was 0.372. The PhiST values estimated through an analysis of molecular variance to assess genetic differentiation among isolates revealed no genetic differentiation among them. Our results revealed very low genetic diversity among isolates, a lack of differentiation, and no association with their geographic origin and the clinical characteristics.
Assuntos
Candida glabrata/classificação , Candidíase/microbiologia , Variação Genética , Antifúngicos/farmacologia , Candida glabrata/efeitos dos fármacos , Candida glabrata/genética , Candida glabrata/isolamento & purificação , Candidíase/fisiopatologia , Eletroforese em Gel de Amido/métodos , Enzimas/análise , Humanos , Testes de Sensibilidade Microbiana , Técnicas de Tipagem Micológica , Técnica de Amplificação ao Acaso de DNA PolimórficoRESUMO
Four human cases of localized cutaneous leishmaniasis caused by Leishmania naiffi are reported. Two of the cases were infected in French Guiana, one in French Guiana or Martinique, and the other in Ecuador or Peru. The geographical distribution of L. naiffi is clearly larger than that initially reported. Three zymodemes were represented by the four isolates, confirming that there is intraspecific polymorphism in L. naiffi.
Assuntos
Leishmania/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Adulto , Animais , Eletroforese em Gel de Amido/métodos , Feminino , Humanos , Leishmania/classificação , Leishmania/enzimologia , Masculino , América do SulRESUMO
Multilocus enzyme electrophoresis (MLEE) of 99 Brucella isolates, including the type strains from all recognized species, revealed a very limited genetic diversity and supports the proposal of a monospecific genus. In MLEE-derived dendrograms, Brucella abortus and a marine Brucella sp. grouped into a single electrophoretic type related to Brucella neotomae and Brucella ovis. Brucella suis and Brucella canis formed another cluster linked to Brucella melitensis and related to Rhizobium tropici. The Brucella strains tested that were representatives of the six electrophoretic types had the same rRNA gene restriction fragment length polymorphism patterns and identical ribotypes. All 99 isolates had similar chromosome profiles as revealed by the Eckhardt procedure.
Assuntos
Brucella/classificação , Brucelose/microbiologia , Laticínios/microbiologia , Variação Genética , Animais , Brucella/enzimologia , Brucella/genética , Brucella/isolamento & purificação , Bovinos , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Ribossômico/análise , DNA Ribossômico/genética , Cães , Eletroforese em Gel de Amido/métodos , Enzimas/análise , Humanos , Hibridização de Ácido Nucleico , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , RibotipagemRESUMO
The genetic relatedness among 96 invasive Escherichia coli belonging to several serogroups and 13 non-invasive of several serotypes that share the same O antigen was investigated by multilocus enzyme electrophoresis analysis. The invasive strains were isolated in different parts of the world and most of them recovered from dysentery. Twenty-nine electrophoretic types were distinguished and the most invasive strains were found to belong to two major lineages. These results suggested that the invasive ability in these strains has evolved in divergent chromosomal backgrounds, presumably through the horizontal spread of plasmid-borne invasion genes. The maintenance of invasive phenotypes in separate lineages suggests that this ability confers a selective advantage to invasive strains.
Assuntos
Escherichia coli/genética , Disenteria/microbiologia , Eletroforese em Gel de Amido/métodos , Escherichia coli/classificação , Escherichia coli/enzimologia , Humanos , Fenótipo , Polimorfismo Genético/genética , Análise de Sequência de DNA , SorotipagemRESUMO
Twenty-three strains of Clostridium argentinense, C. subterminale, C. hastiforme, and other phenotypically similar asaccharolytic clostridia recently placed in seven DNA hybridization groups were compared by multilocus enzyme electrophoresis. The three nontoxigenic strains of C. argentinense were most closely related to the toxigenic strains of this species. All nine toxigenic strains of C. argentinense belonging to a single DNA hybridization group had identical enzyme types on the basis of nine enzymes. All other strains except for two derived from the type strain of C. subterminale were differentiable. Overall, there was excellent agreement between DNA relatedness and multilocus enzyme electrophoresis results.
Assuntos
Clostridium botulinum/classificação , Clostridium/classificação , Enzimas/genética , Clostridium/enzimologia , Clostridium/genética , Clostridium botulinum/enzimologia , Clostridium botulinum/genética , DNA Bacteriano/genética , Eletroforese em Gel de Amido/métodos , FenótipoRESUMO
The clinical and genetic properties of an unusual O-chain variant of human haemoglobin are described. It constitutes less than 1 percent of the total haemoglobin in heterozygotes and, when inherited together with an O-thalassaemia gene, produces the clinical picture of haemoglobin-H disease. Preliminary structural studies indicatge that, in addition to the 141 aminoacid residues which constitute the normal O-chain, this variant has about 31 extra residues attached to the C-terminal end.(SUMMARY)