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1.
Mol Ecol ; 9(9): 1349-61, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10972774

RESUMO

Allelic and genotypic variation at 13 different enzyme loci of autochthonous European beech (Fagus sylvatica L.) was investigated in six 110-160-year-old stands growing at elevations between 150 and 660 m above sea level on the western slope of mount Vogelsberg in central Germany. The highest elevated population showed the highest number of effective alleles (Ne), the highest total heterozygosity (He) and the highest population differentiation deltaT. Also, the genotype SKD-A2A3 of shikimate dehydrogenase was significantly more frequent at the two highest elevated stands (P = 11%) than at the three lowest elevated stands (P = 1%). Further differences in genotype frequencies between 11 of 15 stand pairs were elevation independent.


Assuntos
Árvores/genética , Oxirredutases do Álcool/genética , Alelos , Altitude , Ecossistema , Frequência do Gene , Variação Genética , Genética Populacional , Genótipo , Alemanha , Heterozigoto , Seleção Genética , Árvores/enzimologia
2.
Electrophoresis ; 19(5): 745-51, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9629909

RESUMO

Molecular size and net charge of isoforms of pathogenesis-related (PR) chitinase, beta-1,3-glucanase and peroxidase were studied in uninfected barley (Hordeum vulgare L., v. Karat) leaves and in barley leaves infected with the pathogenic fungus Drechslera teres f. teres (Sacch.) Shoem. Molecular characteristics were determined by time-dependent polyacrylamide gradient gel electrophoresis under native conditions and by applying an extended version of the computer program MOL-MASS (Rothe, G. M., Weidmann, H., Electrophoresis 1991, 12, 703-709). Uninfected barley leaves contained predominantly one peroxidase isozyme but also three very weak peroxidases. Activities of all of these three peroxidases increased considerably after infection with Drechslera teres. The molecular masses of peroxidases 1 and 3 were estimated to be 38 +/- 5 and 42 +/- 7 kDa and their apparent valences at pH 8.4 were Z = 3.13 and 3.20, respectively. Amongst the chitinase isoforms, chitinase 1 and chitinase 2 appeared after infection, while chitinase 3 was also observed in uninfected leaves of barley. The molecular mass of chitinase 3 (31 +/- 6 kDa; f/fo = 1.20) was larger than that of chitinase 1 (20 +/- 2 kDa; f/fo = 1.04) and chitinase 2 (23 +/- 3 kDa; f/fo = 1.06). The valence of constitutive chitinase 3 (Z = 1.44 +/- 0.81) at pH 8.4 was lower than that of adaptive chitinase 1 (Z = 3.27 +/- 1.02) and chitinase 2 (Z = 2.96 +/- 1.38). Infection of barley leaves with Drechslera teres also induced the hydrolytic enzyme beta-1,3-glucanase 1; beta-1,3-glucanase 2 appeared in uninfected and in infected leaves. Constitutive beta-1,3-glucanase 2 was smaller (molecular mass 19 +/- kDa; f/fo = 1.05) than adaptive beta-1,3-glucanase 1 (molecular mass 26 +/- 4 kDa; f/fo = 1.07). The valence of adaptive beta-1,3-glucanase 1 (Z = 9.58 +/- 4.17) was approximately threefold that of beta-1,3-glucanase 2 (Z = 2.80 +/- 0.93).


Assuntos
Quitinases/análise , Helminthosporium/fisiologia , Hordeum/enzimologia , Hordeum/microbiologia , Peroxidase/análise , beta-Glucosidase/análise , Eletroforese em Gel de Poliacrilamida/métodos , Glucana 1,3-beta-Glucosidase , Peso Molecular
3.
Tree Physiol ; 18(5): 325-332, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-12651372

RESUMO

We studied effects of season and soil treatments (watering, acidification, liming and combinations of these treatments) on soluble carbohydrates of mycorrhizal roots of Norway spruce (Picea abies (L.) Karst.). Arabinose, arabitol, fructose, glucose, inositol, lactose, mannitol, pinite, quinate, raffinose, shikimate, stachyose and trehalose were identified by HPLC. Concentrations of inositol, lactose and pinite were constant throughout the year, whereas concentrations of raffinose, stachyose and trehalose were higher in winter than in summer, and concentrations of glucose, fructose and mannitol increased from February to September. Soil acidification and liming had no effect on the annual mean concentrations of fructose, glucose, lactose, pinite, raffinose and stachyose. Liming increased quinate concentrations and decreased arabitol concentrations. Annual mean concentrations of arabinose and mannitol decreased in response to soil acidification. Annual mean concentrations of inositol increased in response to irrigation. None of the soil treatments affected the mean annual concentration of trehalose.

4.
Electrophoresis ; 12(10): 703-9, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1802688

RESUMO

A computer program written in Turbo C is described, which uses the two-step mathematical procedure published recently (Rothe, G. M., Electrophoresis 1988, 9, 307-316) to evaluate the molecular mass, Stokes' radius, spherical radius, and frictional coefficient of nondenatured proteins. The program runs on any IBM-PC or 100% compatible IBM-PC, provided the disk operating system MS-DOS or PC-DOS 3.0 or later has been installed. Functions that are permanently in use are accessible by menu. Storage and loading of data from disk and help instructions can be called by use of function keys. The program provides several tables into which inserted and calculated data is automatically integrated. Each table can be printed out, provided a printer with IBM character set is connected to the computer.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Proteínas/química , Software , Matemática , Modelos Químicos , Peso Molecular
5.
Electrophoresis ; 9(7): 307-16, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3234369

RESUMO

Molecular mass, Stoke's radius, frictional coefficient and isomer-type of non-denatured proteins can be obtained by time-dependent gradient gel electrophoresis by evaluating the resulting data using a two-step mathematical procedure. Provided a histochemical staining procedure is available to locate the position of an enzyme in the gel, crude cell extracts can be used for estimating their molecular size properties. The computation of molecular properties of non-denatured proteins is demonstrated for isozymes of aspartate aminotransferase (EC 2.6.1.1), peroxidase (EC 1.11.1.42) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) from current-year needles of spruce. The resulting data as well as those which were calculated for esterase (EC 3.1.1.1), glutamate dehydrogenase (EC 1.4.1.4), isocitrate dehydrogenase (EC 1.4.1.42), and shikimate dehydrogenase (EC 1.1.1.25) are in accordance with those reported in the literature. The method described may be applied to various scientific areas such as genetics or environmental pollution. It could be shown here that current-year needles of injured spruce (damage class 3) contained two more peroxidase isozymes and one more glucose-6-phosphate dehydrogenase isozyme than those from non-injured trees. These differences may mark two genotypes of spruce of different susceptibilities towards present-day air and soil pollutants.


Assuntos
Proteínas de Plantas/análise , Calibragem , Catálise , Eletroforese em Gel de Poliacrilamida , Enzimas/análise , Peso Molecular , Reprodutibilidade dos Testes , Estereoisomerismo
6.
Planta ; 157(4): 358-66, 1983 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24264270

RESUMO

Pea plants grown under different conditions of cultivation, and eight different plant species with variegated leaves were used to study the intracellular localization of shikimate oxidoreductase (EC 1.1.1.25), the marker enzyme of the pre-chorismate pathway. The two series of experiments indicated an intra-and an extraplastidic compartimentalization of the enzyme, and both enzyme activities are regulated differentially. While the extraplastidic activity is permanently demonstrable, the intraplastidic activity is subject to the plants' developmental state and also depends on both illumination and fertilization.

8.
Hum Genet ; 56(2): 129-55, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7005075

RESUMO

A survey on the formation of secondary isozymes (= multiple molecular forms of enzymes) is given by means of well-documented enzyme systems. Further examples of a certain type of formation are summarized in tabular form. Eight different classes of enzyme variants deriving from translational processes are discussed. These are: aggregation, polymerization, oxidation and reduction of free SH groups, limited proteolysis, cleavage of carbohydrate residues, deamidation, noncovalent binding of coenzymes, and conformational isomerism. In addition, the intracellular distribution of secondary isozymes is discussed, as are the formation of artificial enzyme variants and the recognition of multiple enzyme forms caused by an exchange of neutral amino acids. About 200 original papers are cited. The reference list was completed in early 1979.


Assuntos
Isoenzimas/metabolismo , Aminoácidos/metabolismo , Animais , Metabolismo dos Carboidratos , Coenzimas/metabolismo , Glucuronidase/metabolismo , Humanos , Isoenzimas/classificação , Isoenzimas/genética , Isomerismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Substâncias Macromoleculares , Oxirredução , Peptídeo Hidrolases , Polímeros/metabolismo , Biossíntese de Proteínas , Conformação Proteica , Frações Subcelulares/enzimologia , Compostos de Sulfidrila/metabolismo , Distribuição Tecidual
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