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111.
The phenolic acids and abscisic acid (ABA) of sugar pine ( Pinus lambertiana Dougl.) embryos and megagametophytes, separated by high-pressure liquid chromatography, were analyzed during 90 days stratification of the seeds. The phenolic acids occurred mainly as glycosides. Following hydrolysis, the majority of phenolics present could be identified as common benzoic and ciranamic acid derivatives. Levels of phenolic acids were relatively low in dormant seeds, but increased substantially in the embryos during stratification at 5°C, particularly cinnamic acid, p -coumaric acid, ferulic acid, and one unknown. This active synthesis during stratification did not support an inhibitory function for phenolic acids. During stratification at 5°C, changes in ABA levels in both tissues followed a triphasic pattern, with no loss during the first 30 days, a significant decrease the second 30 days, and a lesser decrease the last 30 days. Loss of ABA from moist seeds at 25°C occurred three times as rapidly, so that by 30 days the ABA level of these seeds was equivalent to that of seeds stratified 90 days at 5°C; however, dormancy was not alleviated at 25°C. Application of exogenous ABA (10−7 to 10−4 M) to stratified seeds did not significantly reduce germination. Together, the above results did not support a primary role for ABA in the maintenance of dormancy in sugar pines.
A correlated increase in phenylpropanoid metabolism and respiratory capacity with increased germinability during stratification suggests that loss of dormancy may be more closely dependent on increased levels of growth promoters or shifts in metabolic pathways. 相似文献
A correlated increase in phenylpropanoid metabolism and respiratory capacity with increased germinability during stratification suggests that loss of dormancy may be more closely dependent on increased levels of growth promoters or shifts in metabolic pathways. 相似文献
112.
E.Ellen Billett Rente J. Grayer-Barkmeijer C.B. Johnson J.B. Harborne 《Phytochemistry》1981,20(6):1259-1263
The major phenolic acid found in gherkin tissues is p-coumaric acid, although cinnamic and caffeic acids are also present; these occur both free an 相似文献
113.
Identification of the predominant constituents produced by the plus and the minus strains of Blakeslea trispora is described. The occurrence of xylenes in the volatiles produced by the plus strain is reported. Additionally, production of 3-hydroxy-3-methylbutanal by the plus strain and dimethyl allyl alcohol by the minus strains were confirmed. Isoamyl alcohol, 1-octen-3-ol, 3-octanol and β-phenethyl alcohol were identified in volatiles from both strains. 相似文献
114.
Ferdinand Bohlmann Christa Zdero Robert M. King Harold Robinson 《Phytochemistry》1980,19(12):2663-2668
The investigation of three Eremanthus species afforded, in addition to known compounds, several new sesquiterpenelactones, a cumambrin B isobutyrate, four lactones related to the eremantholides, two to zexbrevin and one to goyazensolide. Furthermore, a new coniferyl alcohol derivative was isolated. The overall picture of the genus is very uniform. The occurrence of eremanthine and germacranolides with a furanone ring seems to be especially typical. 相似文献
115.
Nocardia sp. DSM 1069 was grown on mineral salt media with coniferyl alcohol, 4-methoxybenzoic acid, 3-methoxybenzoic acid or veratric acid as sole sources of carbon and energy. During incubation on coniferyl alcohol, the formation of coniferyl aldehyde, ferulic acid and quantitative accumulation of vanillic acid and proteocatechuic acid could be achieved with mutants. Washed cell suspensions of N. sp. grown on 4-methoxybenzoic acid, oxidized 4-hydroxybenzoic acid and protocatechuic acid. Cells grown on veratric acid, oxidized vanillic acid, isovanillic acid, and protocatechuic acid. Cell extracts were shown to cleave protocatechuic acid by ortho-fission.A mutant without protocatechuate 3,4-dioxygenase activity was not influenced in its growth on 3 methoxybenzoic acid. Cell free extracts of cells grown on 3-methoxybenzoic acid were shown to catalyze the oxidation of gentisic acid (2,5-dihydroxybenzoic acid). The resulting ring cleavage product was further metabolized by a glutathione dependent reaction.The specificity of the demethylation reactions has been investigated with a mutant unable to grow on vanillic acid. This mutant was not impaired in the degradation of isovanillic acid, 4-methoxy-, or 3-methoxybenzoic acid, whereas growth of this mutant on veratric acid (3,4-dimethoxybenzoic acid) was only half as much as that of the wild type. Concomitantly with growth on veratric acid this mutant accumulated vanillic acid with a yield of about 50%.A pathway for the catabolism of coniferyl alcohol, involving oxidation and shortening of the side chain, and of 4-methoxybenzoic acid and veratric acid with protocatechuic acid as intermediate is being proposed. A second one is proposed for the degradation of 3-methoxybenzoic acid with gentisic acid as intermediate. 相似文献
116.
117.
Total cellular RNA from anaerobically stressed maize seedling roots was used to stimulate in vitro translation of authentic maize alcohol dehydrogenase (ADH) in a rabbit reticulocyte lysate system. Total products from such reactions were displayed on NEPHGE-SDS two-dimensional gels and the Adhl-specific translation products were identified by using RNA from sib seedlings segregating for Adhl charge and size variants. The application of a rapid RNA isolation procedure allowed the efficient isolation of biologically active RNAs from small amounts of seedling material. Maize ADHs translated in vitro are identical in size to in vivo ADH. Further, no ADH was detected in the products of an in vitro translation reaction stimulated by total RNA from aerobically grown seedlings. This suggests that induction of ADH protein by anaerobic stress is accomplished by production of Adh mRNA rather than activation of sequestered mRNA. The mRNAs for maize ADH1 and ADH2 are among a small class of mRNAs induced during anaerobiosis.Research was supported by NSF Grant PCM 76-11009. M.D.B. is supported by National Institute of Health Grant PHS 5 T32 GM07227-04. R.J.F. is a Predoctoral Trainee in Genetics supported by National Institute of Health Training Grants 82 and 7757 from the National Institute of General Medical Sciences. 相似文献
118.
Roger S. Holmes 《Biochemical genetics》1979,17(5-6):461-472
An electrophoretic variant previously reported for the stomach isozyme of alcohol dehydrogenase (ADH-C2) in inbred strains of Mus musculus (Holmes, 1977) has been used to localize the gene encoding this enzyme (Adh-3) on chromosome 3 near Va (varitint) (9.6 ± 3.6% recombinants). Genetic variation of ADH-C2 activity in male and female reproductive tissues among inbred strains and Harwell linkage testing stocks was also observed. Reproductive tissue ADH-C2 phenotypes were inherited in a normal Mendelian fashion among F2 progeny of an F1 (LII × C57BL/Go) × C57BL/Go backcross as though controlled by a single cis-acting regulator locus (designated Adt-1) with two alleles: Adt-1
a (presence of ADH-C2) and Adt-1
b (absence or low activity of ADH-C2). No recombinants were observed among 73 progeny or among 13 inbred strains and six Harwell linkage testing stocks of mice, indicating that Adh-3 and Adt-1 are closely linked or identical genes. A single recombinant phenotype was observed in Peru-Coppock mice, suggesting that they are separate genes. Ontogenetic analyses demonstrated that ADH-B2 is present throughout development from late fetal stages in stomach, liver, and kidney; similar results were found for ADH-C2 in developing kidney and stomach extracts, whereas ADH-A2 exhibited high activity in liver extracts after 3 weeks of age in both sexes and in male kidney extracts after 6 weeks. 相似文献
119.
Changes in the activity of phosphorylase were measured during storage of potatoes at + 2° when the sugar content rises rapidly and subsequently at + 10° when the accumulated sugar is converted mainly to starch. The observed changes were relatively small and could not be related to any of the components of the phosphorylase system, which was shown to be complex. 相似文献
120.
Genetics of alcohol dehydrogenase in Saccharomyces cerevisiae: I. Isolation and genetic analysis of adh mutants 总被引:1,自引:0,他引:1
M. Ciriacy 《Mutation research》1975,29(3):315-325
On the basis of allyalcohol resistance, Saccharomyces cerevisiae mutanta were isolated that were deficient in alcohol dehydrogenase (ADH). The mutants were divided into three classes by their different ADH isozyme pattern obtained after starch-gel electrophoresis: adc mutants that did not produce the constitutive ADH, adr mutants from which the glucose repressible enzyme (ADHII) was absent, and adm mutants deficient in ADH activity associated with the mitochondria.Genetic analysis showed that two genes control synthesis of the glucose repressible enzyme ADHII, one gene the constitutive ADHI and a fourth nuclear gene the mitochondrial ADH. None of these four genes showed any linkage.The various mutant types did not show drastic effects on yeast growth on media containing glucose or ethanol as sole carbon sources. 相似文献