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1.
R. Wijnsma R. Verpoorte Th. Mulder-Krieger A.Baerheim Svendsen 《Phytochemistry》1984,23(10):2307-2311
From callus cultures of Cinchona ledgeriana seven known anthraquinones, purpurin, anthragallol-1,2-dimethylether, anthragallol-1,3-dimethylether, rubiadin, 1-hydroxy-2-hydroxymethylanthraquinone, 1-hydroxy-2-methylanthraquinone and morindone-5-methylether (or 1,7-dihydroxy-8-methoxy-2-methylanthraquinone), and eight new anthraquinones, 5,6-dimethoxy-1-(or -4-)hydroxy-2-(or -3-)hydroxymethylanthraquinone, 5-methoxy-2-(or -3-)methyl-1,4,6-trihydroxyanthraquinone, 2-hydroxy-1,3,4-trimethoxyanthraquinone, 4-methoxy-1,3,5-trihydroxyanthraquinone, 1,4-dimethoxy-2,3-methylenedioxyanthraquinone, 1,3-dihydroxy-4-methoxyanthraquinone, 1,3-dihydroxy-2,5-dimethoxyanthraquinone and 2,5-(or 3,5-)dihydroxy-1,3,4-(or -1,2,4-)trimethoxyanthraquinone have been isolated. 相似文献
2.
Martin Bomar Jo Hermans Titia M. Meesters Rommert C. van den Bos Alexander J. B. Zehnder 《Current microbiology》1989,19(1):35-38
Similarities between the nitrogen-fixing systems of the archaebacteriumMethanosarcina barkeri (strain Fusaro) and a number of eubacteria were investigated. Using antibodies againstRhizobium leguminosarum nitrogenase and a probe of clonednif-HDK genes of this species, homology withM. barkeri was demonstrated on the protein level and to a greater extent on the DNA level. 相似文献
3.
R. Wijnsma J. T. K. A. Go I. N. van Weerden P. A. A. Harkes R. Verpoorte A. Baerheim Svendsen 《Plant cell reports》1985,4(5):241-244
The addition of autoclaved mycelia of Aspergillus niger and the known phytopathogenic fungus Phytophtora cinnamomi to cultured cells of Cinchona ledgeriana Moens. caused a marked increase in the anthraquinone content of the plant cells. This finding in combination with the antimicrobial activity of the anthraquinones isolated from calli of Cinchona pubescens Vahl. led to the conclusion that anthraquinones are phytoalexins.Abbreviations 2,4-D
2,4-dichlorophenoyacetic acid
- TLC
thin-layer chromatography
- AQ
anthraquinone
- DW
dry weight 相似文献
4.
Peter A. A. Harkes Leny Krijbolder Kees R. Libbenga Rommert Wijnsma Theodore Nsengiyaremge Robert Verpoorte 《Plant Cell, Tissue and Organ Culture》1985,4(3):199-214
Using the methods reported by De Fossard et al. (11) the influence of various media constituents on the growth and the alkaloid and anthraquinone production in Cinchona ledgeriana callus cultures was studied. Growth and indole alkaloid production (e.g. cinchonamine) was improved by higher auxin levels. The best growth was observed in the light, although many media resulted in no growth at all in the light. Anthraquinone production was highest at lower auxin levels. Quinoline alkaloid levels (e.g. quinidine) were highest in media with low auxin concentrations. Low and medium cytokinin concentration benefited the quinoline alkaloid production.From the results it was concluded that the pathways leading to the various secondary products, anthraquinones, indole alkaloids and quinoline alkaloids are, at least partly, regulated independently.Abbreviations used IAA
indol-acetic acid
- IBA
indol-butyric acid
- NAA
-naphtaleneacetic acid
- NOA
2-naphtoxy-acetic acid
- 2,4-D
2,4-dichlorophenoxy-acetic acid
- pCPA
parachlorophenoxy-acetic acid
- BA
benzyladenine 相似文献
5.
Rommert Wijnsma Robert Verpoorte Peter A. A. Harkes Theo B. Van Vliet Hens J. G. Ten Hoopen Anders Baerheim Svendsen 《Plant Cell, Tissue and Organ Culture》1986,7(1):21-29
The influence of initial concentrations of two of the major medium components, sucrose and nitrate, on the growth and the production of alkaloids and anthraquinones in cell suspension cultures of Cinchona ledgeriana Moens was studied. It was found that maximum growth and maximum alkaloid yield were obtained with a B5-medium containing the normal level of nitrate and 4% sucrose, whereas the anthraquinone yield was maximum at 8% sucrose at the normal level of nitrate. Maximum contents of secondary metabolites, expressed as g.gDW-1, were found using a medium containing 2% sucrose, but four times the normal nitrate concentration. 相似文献
6.
7.
Jan G. J. Hontelez René Klein Lankhorst Panagiotis Katinakis Rommert C. van den Bos Albert van Kammen 《Molecular & general genetics : MGG》1989,218(3):536-544
Summary On the Rhizobium leguminosarum PRE sym plasmid, fixABC and a novel gene fixW were identified upstream of the regulatory gene nifA. The molecular masses of FixABC, 29, 44 and 50 kDa respectively, were estimated by polyacrylamide gel electrophoresis (PAGE) and of FixW, 25 kDa, by PAGE and nucleotide sequencing. Hybridization studies using bacteroid mRNA as a probe showed that fixABC is one operon which can be transcribed independently of fixW. Nucleotide sequencing revealed that both fixW and fixA are preceded by a nif consensus promoter. The fixA promoter partly overlaps the 3-terminal coding region of fixW, indicating that readthrough from fixW into fixA is possible. Two open reading frames, ORF71 and ORF79, precede fixW and form one operon with fixW. ORF71 contains sequences homologous to the fixA promoter and 5-terminal coding region. One more duplication of fixA sequences was detected, also located within the sym plasmid nif/fix clusters. One duplication of fixW sequences was found. No fixW homologue could be found in other nitrogen fixing organisms except in a number of R. leguminosarum strains. 相似文献
8.
H. J. Wichers R. Wijnsma J. F. Visser TH. M. Malingré H. J. Huizing 《Plant Cell, Tissue and Organ Culture》1985,4(1):61-73
The endogenous synthesis of 3-(3,4-dihydroxyphenyl)-L-alanine (L-DOPA) by cell suspension cultures of Mucuna pruriens was found to be influenced by several environmental parameters. The nature of the nitrogen source as well as the concentration of nitrogen containing salts, sucrose and phosphate in the culture medium were found to affect the biosynthesis of L-DOPA. Addition of 2, 4-dichlorophenoxyacetic acid to the medium suppressed L-DOPA production; continuous illumination of the cultures had a strong beneficial effect on L-DOPA production. L-DOPA was accumulated intracellularly by the cell suspension cultures. These observations further demonstrate that for certain products of plant cell suspensions product synthesis can be manipulated by a proper selection of specified nutrients. 相似文献
9.
Resie M. P. Schetgens Jan G. J. Hontelez Rommert C. van den Bos Albert van Kammen 《Molecular & general genetics : MGG》1985,200(3):368-374
Summary A nif regulatory gene in R. leguminosarum PRE was identified by interspecies DNA hybridization and site-directed Tn5 mutagenesis. Significant homology was found with the K. pneumoniae nifA locus, a R. meliloti symbiotic regulatory gene and E. coli ntrC; Tn5 insertions within this nifA gene inhibit the expression of the nifHDK operon, encoding synthesis of the nitrogenase polypeptides.Specific DNA hybridization also was detected between a downstream adjacent part of the PRE sym plasmid and the R. leguminosarum 248 fixZ gene, a homologue of the K. pneumoniae nifB locus. To detect further fix genes we investigated a region of the sym plasmid which is localized within a short distance upstream from the nifA gene and is transcribed selectively at a high rate during symbiosis. This approach revealed the existence of a fix cluster in which Tn5-mutations cause a Fix- phenotype although wild-type levels of nitrogenase synthesis were detectable. In a sym plasmid fragment, which is immediately upstream adjacent to the nifA locus and only moderately expressed in Rhizobium bacteroids, a second fix gene conferring the same symbiotic phenotype was detected. 相似文献
10.
Identification and Characterization of a Bacteroid-Specific Dehydrogenase Complex in Rhizobium leguminosarum PRE 下载免费PDF全文
Ren M. Klein Lankhorst Panagiotis Katinakis Albert van Kammen Rommert C. van den Bos 《Applied microbiology》1988,54(12):3008-3013
In membranes of Rhizobium leguminosarum bacteroids isolated from nitrogen-fixing pea root nodules, two different protein complexes with NADH dehydrogenase activity were detected. One of these complexes, with a molecular mass of 110 kilodaltons, was also found in membranes of free-living rhizobia, but the other, with a molecular mass of 550 kilodaltons, appeared to be present only in bacteroids. The bacteroid-specific complex, referred to as DH1, probably consists of at least four different subunits. Using antibodies raised against the separate polypeptides, we found that a 35,000-molecular-weight polypeptide (35K polypeptide) in the DH1 complex is bacteroid specific, while the other proposed subunits were also detectable in cytoplasmic membranes of free-living bacteria. Dehydrogenase complex DH1 is also present in bacteroids of a R. leguminosarum nifA mutant, indicating that the synthesis of the dehydrogenase is not dependent on the gene product of this nif-regulatory gene. A possible involvement of the bacteroid-specific DH1 complex in electron transport to nitrogenase is discussed. 相似文献