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1.
Lin Yang Chunyan Yan Jianhua Zhu Liyan Song Rongmin Yu 《World journal of microbiology & biotechnology》2010,26(7):1201-1205
The biocatalytic ability of transgenic crown galls of Panax quinquefolium was evaluated by using eugenol (1) as a substrate and suspension cultures of Nicotiana tabacum as control system. Three biotransformed products, namely: 2-methoxy-4-(2-propenyl)phenyl-O-β-d-glucopyranoside (2, 67.11%), 2-methoxy-4-(2-propenyl)phenyl-O-β-d-glucopyranosyl (6′ → 1″)-β-d-xylopyranoside (3, 2.85%) and methyl eugenol (4, 14.30%) were obtained after 5 days of administration of eugenol to the suspension cultures of transgenic crown galls of
P. quinquefolium. In contrast, only one product, compound 2 (15.41%), was obtained in suspension cultures of N. tabacum after 5 days of incubation. The results indicated that the glycosylation ability of transgenic crown galls of P. quinquefolium was much higher than that of the cultured cells of N. tabacum. 相似文献
2.
Rapid and high frequency shoot regeneration from hypocotyl protoplasts of Brassica nigra 总被引:2,自引:0,他引:2
S. B. Narasimhulu P. B. Kirti Shyam Prakash V. L. Chopra 《Plant Cell, Tissue and Organ Culture》1993,32(1):35-39
Protoplasts, isolated from etiolated hypocotyls of seven day old seedlings of Brassica nigra, were cultured in Kao's liquid medium containing 7.2% glucose, 2,4-d (1 mg 1-1), NAA (0.1 mg 1-1) and zeatin riboside (0.5 mg 1-1). After initial incubation for 3 days in dark at 25±1°C, cultures were transferred to a photoperiod cycle of 16/8 h and diluted on seventh and tenth day with MS medium containing 3.4% sucrose, 2,4-d (0.1 mg 1-1) and BAP (1 mg 1-1). About 62% of the cells divided at least once and 46% of them reached 8–16 cell stage in one week. The dividing cell clusters could be plated on agarose medium on the fifteenth day to obtain proliferating minicalli with a plating efficiency of 1.8%. 56.8% of minicalli, regenerated shoots on a regeneration medium containing 2 IP and IAA at 1 and 0.2 mg 1-1 respectively. The in vitro produced shoots were rooted in MS medium containing 1 mg 1-1 IBA and established in soil without difficulty. The time taken for protoplasts to develop into plants varied from 9 to 10 weeks.Abbreviations 2,4-d
2,4-dichlorophenoxyacetic acid
- BAP
6-benzylaminopurine
- 2 IP
2-isopentenyladenine
- IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid
- NAA
-naphthaleneacetic acid
- Kn
kinetin 相似文献
3.
E. Vollbrecht R. Heckmann V. Wray M. Nimtz S. Lang 《Applied microbiology and biotechnology》1998,50(5):530-537
The bacterium Tsukamurella sp. nov., isolated from soil, was found to produce novel glycolipids when grown on sunflower oil as the sole carbon source.
The glycolipids were isolated by chromatography on silica columns and their structures elucidated using a combination of multidimensional
NMR and MS techniques. The three main components are 2,3-di-O-acyl-α-d-glucopyranosyl-(1-1)-α-d-glucopyranose, 2,3-di-O-acyl-β-d-glucopyranosyl-(1-2)-4,6-di-O-acyl-α-d-glucopyranosyl-(1-1)-α-d-glucopyranose and 2,3-di-O-acyl-β-d-glucopyranosyl-(1-2)-β-d-galactopyranosyl-(1-6)-4,6-di-O-acyl-α-d-glucopyranosyl-(1-1)-α-d-glucopyranosl which are linked to fatty acids varying in chain length from C4 to C18. The glycolipids are mainly extracellular but are also found attached to the cell walls. During the cultivation the composition
of the glycolipids changed from disaccharide- to tri- and tetrasaccharide lipids. The glycolipids show good surface-active
behaviour and have antimicrobial properties.
Received: 22 May 1998 / Received revision: 24 August 1998 / Accepted: 26 August 1998 相似文献
4.
Antimicrobial activity of crude seed extract of Moringa oleifera was investigated by thin layer chromatography bioassay against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Cladosporium cladosporioides, and Penicillium sclerotigenum; most of them were prominently inhibited by an isolate with R
F 0.92–0.96. Characterization and identification of the extract revealed the occurrence of three bioactive compounds: 4-(α-l-rhamnopyranosyloxy)benzyl isothiocyanate, methyl N-4-(α-l-rhamnopyranosyloxy) benzyl carbamate (both known compounds), and 4-(β-d-glucopyranosyl-1→4-α-l-rhamnopyranosyloxy)-benzyl thiocarboxamide, existence of which in any Moringa spp. or plant is reported for the first time. The UV spectrum of the novel compound showed maximum absorption at 273 and
225 nm in MeOH while the IR spectrum revealed several characteristic bands at 3100, 2900, 1700, 1500, 1300, 1100 and 1000
cm−1. The 1H-NMR showed signals at 1.2 and 3.77 ppm and the 13C-NMR presented signals at 155, 122, 91.7 and 98.4 ppm. All the compounds at 5 mg/L had very high bactericidal activity against
some of test pathogens even at contact period 1–2 h. 4-(β-d-Glucopyranosyl-1→4-α-l-rhamnopyranosyloxy)benzyl thiocarboxamide was the most potent, with 99.2 % inhibition toward Shigella dysenteriae and 100 % toward Bacillus cereus, E. coli and Salmonella typhi within 4 h of contact. 相似文献
5.
The rumen anaerobic fungusPiromonas communis, unlike the rumen anaerobic fungiNeocallimastix frontalis andNeocallimastix patriciarum, produced extracellular α-(4-O-methyl)-d-glucuronidase when grown in cultures containing filter-paper, barley straw, birchwood xylan or birchwood sawdust as carbon
source. The highest concentration of enzyme was produced in cultures containing birchwood sawdust. The aldobiouronic acidO-α-(4-O-methyl-d-glucopyran-osyluronic acid)-(1 → 2)-d-xylopyranose (MeGlcAXyl) was the best substrate of those tested: the aldotriouronic acidO-α-(4-O-methyl-d-glucopyranosyluronic acid (1 → 2)-O-\-d-xylopyranosyl-(1 → 4)-d-xylopyranose (MeGlcAXyl2) and the aldotetraouronic acidO-α-(4-O-methyl-d-glucopyranosyluronic acid)-(1 → 2)-O-\-d-xylopyranosyl-(1 → 4)-O-\-d-xylopyranosyl-(1 → 4)-d-xylopyranose (MeGlcAXyl3) were also attacked but the rate fell as the degree of polymerisation increased. When the same substituted xylooligosaccharides
were reduced to the corresponding alditols the enzyme activity disappeared. Similarly,p-nitrophenyl-α-d-glucuronide was not a substrate. Remarkably, the relative rates of attack shown by the α-(4-O-methyl)-d-glucuronidase on the aldouronic acids and on xylans extracted from birchwood, oat spelts and oat straw differed according
to the carbon source used to produce the enzyme. The α-(4-O-methyl)-d-glucuronidase had a pH optimum of 5.5 and a temperature optimum of 50°C. On gel filtration the enzyme was shown to be associated
with proteins covering the range 100–300 kDa, but a major peak of activity in the column effluent appeared to have a molecular
mass of 103 kDa. 相似文献
6.
I. B. Naumova N. V. Potekhina C. Duigimbaye A. S. Shashkov L. P. Terekhova T. P. Preobrazhenskaya 《Archives of microbiology》1986,146(3):256-262
The cell walls of Actinomadura carminata INA 4281 were found to contain peptidoglycan, teichoic acid, and nonpeptidoglycan amino acids. The peptidoglycan was of the A1 type and contained a small amount of ll-DAP in addition to m-DAP. The teichoic acid was an 1,3-poly(glycerol phosphate) chain composed of about eight glycerophosphate units, two of which had a 2-acetamido-2-deoxy--d-galactopyranosyl substituent and one, a 3-O-methyl--d-galactopyranosyl-(1 3)-2-acetamido-2-deoxy--d-galactopyranosyl residue at C2 of glycerol. The structure of the polymer was identified by chemical analysis and 13C-NMR spectroscopy. The teichoic acid contained 3-O-methyl-d-galactose (madurose) — the first ever finding of this compound within a teichoic acid. The nonpeptidoglycan amino acids made up some 30% of the cell wall's dry weight, about a quarter of the amino acids being removable with sodium dodecyl sulfate. Further treatment of the cell walls with LiCl and guanidine hydrochloride caused only a small loss of the amino acids and slight changes in their molar ratio.Abbreviations Gro
glycerol
- GroP
monophosphate glycerol
- GroP2
diphosphate glycerol
- Gro2P
-monophosphate glycerol
- PTA
phosphorus of teichoic acids
- PNA
phosphorus of nucleic acids
- TA
teichoic acid 相似文献
7.
Using primary hepatocytes in culture, various 2-acetamido-2-deoxy-D-glucose (GlcNAc) analogs were examined for their effects on the incorporation of D-[3H]glucosamine, [35S]sulfate, and L-[14C]leucine into cellular glycoconjugates. A series of acetylated GlcNAc analogs, namely methyl 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-α-(3) and β-D-glucopyranoside (4) and 2-acetamido-1,3,4,6-tetra-O-acetyl-2-deoxy-D-glucopyranose (5), exhibited a concentration-dependent reduction of D-[3H]glucosamine, but not of [35S]sulfate incorporation into isolated glycosaminoglycans (GAGs), without affecting L-[14C]leucine incorporation into total protein synthesis. These results suggest that analogs 3–5 exhibit an inhibitory effect
on D-[3H]glucosamine incorporation into isolated GAGs by diluting the specific activity of cellular D-[3H]glucosamine and by competing for the same metabolic pathways. In the case of the corresponding series of 4-deoxy-GlcNAc
analogs, namely methyl 2-acetamido-3,6-di-O-acetyl-2,4-dideoxy-α-(6) and β-D-xylo-hexopyranoside (7) and 2-acetamido-1,3,6-tri-O-acetyl-2,4-dideoxy-D-xylo-hexopyranose (8), compound 8 at 1.0 mM exhibited the greatest reduction of D-[3H]glucosamine and [35S]sulfate incorporation into isolated GAGs, namely to ∼7% of controls, and a moderate inhibition of total protein synthesis,
namely to 60% of controls. Exogenous uridine was able to restore the inhibition of total protein synthesis by compound 8 at
1.0 mM. Isolated GAGs from cultures treated with compound 8 were shown to be smaller in size (∼40 kDa) than for control cultures
(∼77 kDa). These results suggest that the inhibitory effects of compound 8 on cellular GAG synthesis may be mediated by the
incorporation of a 4-deoxy moiety into GAGs resulting in premature chain termination and/or by its serving as an enzymatic
inhibitor of the normal sugar metabolites. The inhibition of total protein synthesis from cultures treated with compound 8
suggests a uridine trapping mechanism which would result in the depletion of UTP pools and cause the inhibition of total protein
synthesis. A 1-deoxy-GlcNAc analog, namely 2-acetamido-3,4,6-tri-O-acetyl-1,5-anhydro-2-deoxy-D-glucitol (9), also exhibited a reduction in both D -[3H]glucosamine and [35S]sulfate incorporation into isolated GAGs by 19 and 57%, of the control cells, respectively, at 1.0 mM without affecting
total protein synthesis. The inability of compound 9 to form a UDP-sugar and, hence, be incorporated into GAGs presents another
metabolic route for the inhibition of cellular GAG synthesis. Potential metabolic routes for each analog's effects are presented. 相似文献
8.
Geetha Upadhyaya M. B. Shivanna H. S. Prakash H. S. Shetty 《Plant Cell, Tissue and Organ Culture》1992,31(3):203-206
Dual cultures were successfully established using malformed florets of pearl millet infected with Sclerospora graminicola, the downy mildew pathogen. A higher proportion (86%) of calli from malformed florets formed dual cultures on Murashige and Skoog's (MS) medium with 2 mg 1-1 of 2,4-dichlorophenoxy acetic acid (2,4-d), compared to shoot tips (25%). Fungal mycelium covered the entire surface of the callus within 30 days of placement of explants on the MS medium with 2 mg 1-1 of 2,4-d. The infected calli also differentiated and produced plantlets when transferred to MS medium without 2,4-d. 相似文献
9.
J. Q. Liu M. Odani T. Dairi N. Itoh S. Shimizu H. Yamada 《Applied microbiology and biotechnology》1999,51(5):586-591
A new enzymatic resolution process was established for the production of l-threo-3-[4-(methylthio)phenylserine] (MTPS), an intermediate for synthesis of antibiotics, florfenicol and thiamphenicol, using
the recombinant low-specificity d-threonine aldolase from Arthrobacter sp. DK-38. Chemically synthesized dl-threo-MTPS was efficiently resolved with either the purified enzyme or the intact recombinant Escherichiacoli cells overproducing the enzyme. Under the optimized experimental conditions, 100 mM (22.8 g l−1) l-threo-MTPS was obtained from 200 mM (45.5 g l−1) dl-threo-MTPS, with a molar yield of 50% and a 99.6% enantiomeric excess.
Received: 2 September 1998 / Received revision: 27 October 1998 / Accepted: 29 November 1998 相似文献
10.
Jian Wen Wang Li Ping Zheng Ben Zhang Ting Zou 《Applied microbiology and biotechnology》2009,85(2):285-292
This work examined the accumulation of artemisinin and related secondary metabolism pathways in hairy root cultures of Artemisia annua L. induced by a fungal-derived cerebroside (2S,2′R,3R,3′E,4E,8E)-1-O-β-d-glucopyranosyl-2-N-(2′-hydroxy-3′-octadecenoyl)-3-hydroxy-9-methyl-4,8-sphingadienine. The presence of the cerebroside induced nitric oxide
(NO) burst and artemisinin biosynthesis in the hairy roots. The endogenous NO generation was examined to be involved in the
cerebroside-induced biosynthesis of artemisinin by using NO inhibitors, N
ω-nitro-l-arginine methyl ester and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide. The gene expression and activity
of 3-hydroxy-3-methylglutaryl CoA reductase and 1-deoxy-d-xylulose 5-phosphate synthase were stimulated by the cerebroside, but more strongly by the potentiation of NO. While the
mevalonate pathway inhibitor, mevinolin, only partially inhibited the induced artemisinin accumulation, the plastidic 2-C-methyl-d-erythritol 4-phosphate pathway inhibitor, fosmidomycin, nearly arrested artemisinin accumulation induced by cerebroside and
the combination elicitation with an NO donor, sodium nitroprusside (SNP). With the potentiation by SNP at 10 μM, the cerebroside
elicitor stimulated artemisinin production in 20-day-old hairy root cultures up to 22.4 mg/l, a 2.3-fold increase over the
control. These results suggest that cerebroside plays as a novel elicitor and the involvement of NO in the signaling pathway
of the elicitor activity for artemisinin biosynthesis. 相似文献
11.
The trisaccharide 2-(p-trifluoroacetamidophenyl)ethyl 2-acetamido-2-deoxy-4-O-[2-O-(-l-fucopyranosyl)--d-galactopyranosyl]--d-glucopyranoside 1 and the tetrasaccharide 2-(p-trifluoroacetamidophenyl)ethyl 2-acetamido-2-deoxy-3-O-(-l-fucopyranosyl)-4-O-[2-O-(-l-fucopyranosyl)--d-galactopyranosyl]--d-glucopyranoside 2 were synthesized. Thioglycosides, suitably protected, activated directly with methyl trifluoromethanesulfonate or dimethyl(methylthio)sulfonium tetrafluoroborate or activated after bromine treatment with halophilic reagents, were used as glycosyl donors in the construction of the glycosidic linkages.Abbreviations DMTSB
dimethyl(methylthio)sulfonium tetrafluoroborate
- Phth
phthaloyl
- MBn
p-methoxybenzyl
- ClBn
p-chlorobenzyl 相似文献
12.
Arabinogalactan-proteins (AGPs) are abundant plant proteoglycans that react with (β-d-Glc)3 but not (β-d-Man)3 Yariv reagent. We report here that treatment with (β-d-Glc)3 Yariv reagent caused inhibition of root growth of Arabidopsis thaliana (L.) Heynh. seedlings. Moreover, the treated roots exhibited numerous bulging epidermal cells. Treatment with (β-d-Man)3 Yariv reagent did not have any such effects. These results indicate a role for AGPs in root growth and control of epidermal
cell expansion. Because treatment with (β-d-Glc)3 Yariv reagent phenocopies the reb1 (root epidermal cell bulging) mutant of Arabidopsis, AGPs were extracted from the reb1-1 mutant and compared with those of the wild type. The reb1-1 roots contained an approximately 30% lower level of AGPs than the wild type. More importantly, while the profile of AGPs
from wild-type roots showed two major peaks upon crossed electrophoresis, the profile of AGPs from reb1-1 roots exhibited only one of the major peaks. Therefore, the reb1 phenotype appears to be a result of defective or missing root AGPs. Taken together, this pharmacological and genetic evidence
strongly indicates a function of AGPs in the control of root epidermal cell expansion.
Received: 13 February 1997 / Accepted: 1 April 1997 相似文献
13.
Orfila C Sørensen SO Harholt J Geshi N Crombie H Truong HN Reid JS Knox JP Scheller HV 《Planta》2005,222(4):613-622
An insertion in the promoter of the Arabidopsis thaliana QUA1 gene (qua1-1 allele) leads to a dwarf plant phenotype and a reduction in cell adhesion, particularly between epidermal cells in seedlings
and young leaves. This coincides with a reduction in the level of homogalacturonan epitopes and the amount of GalA in isolated
cell walls (Bouton et al., Plant Cell 14: 2577 2002). The present study was undertaken in order to investigate further the link between QUA1 and cell wall biosynthesis. We have used rapidly elongating inflorescence stems to compare cell wall biosynthesis in wild
type and qua1-1 mutant tissue. Relative to the wild type, homogalacturonan α-1-4-D-galacturonosyltransferase activity was consistently reduced in qua1-1 stems (by about 23% in microsomal and 33% in detergent-solubilized membrane preparations). Activities of β-1-4-D-xylan synthase, β-1-4-D-galactan synthase and β-glucan synthase II activities were also measured in microsomal membranes. Of these, only β-1-4-D-xylan synthase was affected, and was reduced by about 40% in qua1-1 stems relative to wild type. The mutant phenotype was apparent in inflorescence stems, and was investigated in detail using
microscopy and cell wall composition analyses. Using in situ PCR techniques, QUA1 mRNA was localized to discrete cells of the vascular tissue and subepidermal layers. In mutant stems, the organization of
these tissues was disrupted and there was a modest reduction in homogalacturonan (JIM5) epitopes. This study demonstrates
a specific role for QUA1 in the development of vascular tissue in rapidly elongating inflorescence stems and supports a role
of QUA1 in pectin and hemicellulose cell wall synthesis through affects on α-1,4-D-galacturonosyltransferase and β-1,4-D-xylan synthase activities. 相似文献
14.
Ewa Neugebauer Benoit Gamache Claude V. Déry Ryszard Brzezinski 《Archives of microbiology》1991,156(3):192-197
Streptomyces lividans TK24, an established host for genetic and molecular studies in actinomycetes, is able to use chitin as sole carbon and nitrogen source. Extracellular chitinase and N-acetyl--d-glucosamidinase (chitobiase) activities were detected in liquid cultures. Chitinase production was inducible by chitin and its low molecular weight derivatives. Low levels of chitinase were also produced in the absence of chitin. Production of extracellular N-acetylglucosaminidase was correlated with the beginning of the stationary phase of growth and was independent of the presence of chitin. Beside highly N-acetylated chitin, supernatants of chitin-induced cultures were able to hydrolyse chitosans with a wide range of degrees of N-acetylation.Abbreviations MS
minimal salts
- GlcNAc
N-acetyl--d-glucosamine
- pNP-GlcNAc
p-nitrophenyl-2-acetamido-2-deoxy--d-glucopyranoside
- d.a.
degree of N-acetylation
- TLC
thin-layer chromatography 相似文献
15.
Jae Sung Park Gi Hwan Yi Min Hee Nam Sun Ho Park 《Biotechnology and Bioprocess Engineering》2001,6(1):51-55
This study was conducted to establish a plant cell culture system for the production of medically important secondary metabolites
fromXanthium strumarium. The effects of plant growth regulators including NAA, 2,4-D, kinetin, and ABA were examined in terms of callus induction,
maintenance of callus and suspension cultures. It was shown that callus was induced upon treatment with NAA while embryo was
induced after treatment with 2,4-D. Callus formation was further improved by treatment with ABA and NAA. The level of callusing
increased by 17–29% for the seed case, cotyledon, leaf, and hypocotyl and by 96% in the case of the root. Suspension cell
lines were established using calli produced from cotyledon, hypocotyl and root and cultured at 25°C under light conditions.
The cells grew up to 15 g/L with NAA 2 ppm, BA 2 ppm, and ABA 1 ppm treatment. Supernatants of suspension cultures of cell
lines derived from coyledon and hypocotyl produced some distinctive secondary metabolites, one of which was identified as
8-epi-tomentosin, which belongs to the xanthanolides. The amounts of 8-epi-tomentosin produced by the cotyledon-and hypocotylderived cell lines were 13.4 mg/L and 11.0 mg/L, respectively. 相似文献
16.
Glucose-2-oxidase activity and accumulation of D-arabino-2-hexosulose in cultures of the basidiomyceteOudemansiella mucida 总被引:1,自引:1,他引:0
Submerged cultures of the basidiomyceteOudemansiella mucidd, strain III, accumulate D-arabino-2-hexosulose. The maximum yields during cultivations in shaker flasks or in a laboratory fermentor are 6–12 and 15 mg/ml, respectively
(20–50 % conversion of substrate glucose). The accumulation is transient, the aldoketose being again utilized after glucose
exhaustion. Its production is stimulated by fluoride ions. The enzyme responsible for the C(2)-specific oxidation ofd-glucose acts as an intracellular oxidase with a maximum activity in the exponential phase of growth.d-arabino-2-Hexosulose was also detected in the cultivation medium of the wood-rotting fungiPleurotus ostreatus, Laetiporus sulphureus, andPhellinus abietis.
Part III of the series Enzymatic activity of Basidiomycetes; part II:Folia Microbiol.
13, 334 (1968). 相似文献
17.
Production of trehalose synthase from a basidiomycete, Grifola frondosa, in Escherichia coli 总被引:1,自引:0,他引:1
K. Saito H. Yamazaki Y. Ohnishi S. Fujimoto E. Takahashi S. Horinouchi 《Applied microbiology and biotechnology》1998,50(2):193-198
The genomic DNA and cDNA for a gene encoding a novel trehalose synthase (TSase) catalyzing trehalose synthesis from α-d-glucose 1-phosphate and d-glucose were cloned from a basidiomycete, Grifola frondosa. Nucleotide sequencing showed that the 732-amino-acid TSase-encoding region was separated by eight introns. Consistent with
the novelty of TSase, there were no homologous proteins registered in the databases. Recombinant TSase with a histidine tag
at the NH2-terminal end, produced in Escherichia coli, showed enzyme activity similar to that purified from the original G. frondosa strain. Incubation of α-d-glucose 1-phosphate and d-glucose in the presence of recombinant TSase generated trehalose, in agreement with the enzymatic property of TSase that
the equilibrium lay far in the direction of trehalose synthesis.
Received: 12 January 1998 / Received revision: 20 February 1998 / Accepted: 20 March 1998 相似文献
18.
Alain Decendit Pierre Waffo-Teguo Tristan Richard Stphanie Krisa Joseph Vercauteren Jean-Pierre Monti Grard Deffieux Jean-Michel Mrillon 《Phytochemistry》2002,60(8)
Suspension cultures of Vitis vinifera were found to produce catechins and stilbenes. When cells were grown in a medium inducing polyphenol synthesis, (−)-epicatechin-3-O-gallate, dimeric procyanidin B-2 3′-O-gallate and two resveratrol diglucosides were isolated, together with a new natural compound that was identified as cis-resveratrol-3,4′-O-β-diglucoside by spectroscopical methods. 相似文献
19.
Faheem Aftab Yusuf Zafar Kouser A. Malik Javed Iqbal 《Plant Cell, Tissue and Organ Culture》1996,44(1):71-78
Embryogenic callus was developed from young leaves of sugarcane (Saccharum spp.hybrid, cv. CoL-54). A good embryogenic callus response was achieved using MS basal medium containing 2.0 mol (0.5 mg l-1) picloram under dark conditions at 27±1°C. Initiation of fast growing homogeneous cell suspension cultures was achieved in MS and AA media, both supplemented with g mol (2 mg l-1) 2,4-d and 500 mg l-1 CH. Embryogenic callus was reinitiated from embryogenic cell suspension cultures using MS medium containing 30 g l-1 sucrose, 500 mg l-1 CH and 2.26 mol (0.5 mg l-1) 2,4-d after 4–6 weeks of culture under 16-h photoperiod conditions. Plant regeneration was achieved after about 4 weeks in MS medium lacking growth regulators but containing CH (500 mg l-1) and sucrose (60 g l-1). Rooting was enhanced by transferring regenerated plantlets to half strength MS basal medium.Totipotent protoplasts with an average yield of 2.0×107 to 1.0×108 ml-1 were obtained from embryogenic cell suspension cultures at log phase, i.e., 4–5 days after transfer to fresh media. The best growth response was achieved when protoplasts were cultured in a modifed KM8P medium at the density of 2.0×105 m l-1. Protoplasts were mainly embedded in 0.8% sea plaque agarose. Division efficiency of 22.2% was achieved after 20 days of culture and 0.26% of microcolonies continued growth and formed microcalluses after 30 days of culture under dark conditions. Microcalluses were proliferated in MS medium having 2,4-d (2 mg l-1) under 16-h photoperiod. Transferring these embryogenic calluses in MS medium +9.29 mol kinetin (2 mg l-1) +5.37 mol NAA (1.0 mg l-1) + activated charcoal (200 mg l-1) for 5 weeks favoured plant regeneration. Shoots and roots were further proliferated in half strength MS basal medium for 2–4 weeks. Regenerated plants were transferred to autoclaved sand for 2 weeks under 16-h photoperiod in growth room and transferred to soil in a greenhouse to raise to maturity.Abbreviations MS
salts of Murashige & Skoog (1962) basal medium
- AA
salts of Muller & Grafe (1978) basal medium
- N6
saits of Chuet al. (1975) basal medium
- 2,4-d
2,4-dichlorophenoxyacetic acid
- CH
casein hydrolysate
- KM8P
protoplast culture medium of Kao & Michayluk (1975)
- KPR
protoplast culture medium of Kao (1977)
- P9
protoplast culture medium (Chen & Shih, 1983)
- BA
Benzyladenine
- Picloram
4-amino-3,5,6-trichloropicolinic acid
- NAA
Naphthalene acetic acid 相似文献
20.
The control of malate metabolism and stimulation of 1-sinapolyglucose: L-malate sinapoyltransferase (SMT) activity in radish (Raphanus sativus L. var. sativus) cotyledons has been studied. The light-induced and nitrate-dependent activity of SMT catalyzes the formation of O-sinapoly-L-malate via 1-O-sinapoyl--D-glucose. When dark-grown radish seedlings, cultivated in quartz sand with nutrient solution containing NO
3
-
as the sole N source, were treated with light, SMT activity increased concomitantly with free malate in the cotyledons. This light effect was suppressed in seedlings grown in a culture medium which contained in addition to NO
3
-
also NH
4
+
. However, treatment with methionine sulfoximine neutralized this ammonium effect, resulting again in both rapid accumulation of malate and rapid increase in SMT activity. When seedlings grown on NO
3
-
nitrogen were subsequently supplied with NH
4
+
nitrogen, the accumulated level of L-malate rapidly dropped and the SMT increase ceased. The enzyme activity decreased later on, reaching the low activity level of plants which were grown permanently on NO
3
-
/NH
4
+
-nitrogen. An external supply (vacuum infiltration) of malate to excised cotyledons and intact seedings, grown on NO
3
-
/NH
4
+
-nitrogen medium, specifically promoted a dose-dependent increase in the activity of SMT. In summary these results provide evidence indicating that the SMT activity in cotyledons of Raphanus sativus might be related to the metabolism of malic acid.Abbreviation MSO
L-methionine sulfoximine
- SinGlc
1-O-sinapoyl--D-glucose
- SinMal
O-sinapoyl-L-malate
- SMT
1-O-sinapoyl--D-glucose:L-malate sinapolytransferase 相似文献