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1.
Arriagada C Dagnino-Subiabre A Caviedes P Armero JM Caviedes R Segura-Aguilar J 《Amino acids》2000,18(4):363-373
Summary. Aminochrome was found to be toxic in a mouse-derived neuronal cell line (CNh). The effect was concentration dependent (10–150
μM). The issue whether aminochrome toxicity involves glutamate transmission was studied with several glutamate receptors antagonists.
Incubation of the cells with aminochrome (150 μM) in the presence of 100 μM of the AMPA an-tagonist, NBQX resulted in an increase of cell survival, from 52 to 73%. However, this protective effect
did not seem to be related to activation of ionotropic glutamate receptors since incubation of CNh cells with 200 μM of glutamate resulted in only 10% decrease of cell survival. However, NBQX was found to inhibit in vitro the autoxidation process. One hundred μM AP-5 did not have any effect on aminochrome toxicity. The toxic effect of aminochrome on CNh cells seems to be dependent
of extracellular activation since addition of dicoumarol, a specific inhibitor of DT-diaphorase, did not affect that toxicity,
which can be explained perhaps by a lack of a transport system for aminochrome into the CNh cells.
Received July 28, 1999, Accepted December 6, 1999 相似文献
2.
Effects of ultraviolet radiation on photosynthesis and related enzyme reactions of marine macroalgae 总被引:8,自引:0,他引:8
Changes in physiological parameters related to photosynthesis were studied in five macroalgal species from Spitsbergen (Monostroma arcticum, Laminaria solidungula, Alaria esculenta, Palmaria palmata, Phycodrys rubens) during a 72-h exposure to UV radiation. Maximal quantum yield of photochemistry (Fv/Fm) and maximal electron transport rate
(ETRmax) were measured with a pulse-amplitude-modulated fluorometer; the activity of the Calvin cycle enzymes ribulose-1,5-bisphosphate
carboxylase/oxygenase (Rubisco) and glyceraldehyde-3-phosphate dehydrogenase (G3PDH) were estimated using a photometric test.
Proteins of crude extracts were separated by SDS gel electrophoresis and changes in cellular concentrations of Rubisco were
determined. Moreover, the concentration of chlorophyll a (Chl a), and protein content, were measured photometrically. In all species, Chl a content, maximal quantum yield as well as ETRmax decreased during the UV treatment. Changes in ETRmax were related to the
changes in the overall activity of Rubisco. Analysis of SDS gels showed that in P. rubens, L. solidungula, M. arcticum and A. esculenta decreasing Rubisco activity partly resulted from a degradation of the enzyme. However, in A. esculenta, the formation of a high-molecular-weight polypeptide was observed. In all species, the activity of Rubisco was more strongly
impaired than that of G3PDH. Exposure to UV resulted in loss of total protein only in the deepwater species L. solidungula and P. rubens. The different sensitivities to UV exposure of the species tested reflect their zonation pattern in the field.
Received: 4 October 1999 / Accepted: 15 February 2000 相似文献
3.
Summary. The effect of beta-alanine (β-Ala) alone or in combination with creatine monohydrate (Cr) on aerobic exercise performance
is unknown. The purpose of this study was to examine the effects of 4 weeks of β-Ala and Cr supplementation on indices of
endurance performance. Fifty-five men (24.5 ± 5.3 yrs) participated in a double-blind, placebo-controlled study and randomly
assigned to one of 4 groups; placebo (PL, n = 13), creatine (Cr, n = 12), beta-alanine (β-Ala, n = 14), or beta-alanine plus creatine (CrBA, n = 16). Prior to and following supplementation, participants performed a graded exercise test on a cycle ergometer to determine
VO2peak, time to exhaustion (TTE), and power output, VO2, and percent VO2peak associated with VT and LT. No significant group effects were found. However, within groups, a significant time effect was
observed for CrBa on 5 of the 8 parameters measured. These data suggest that CrBA may potentially enhance endurance performance. 相似文献
4.
Giordano C Lucente G Masi A Paglialunga Paradisi M Sansone A Spisani S 《Amino acids》2007,33(3):477-487
Summary. For-Met-βAlaψ[CSNH]-Phe-OMe (3), For-Met-βAlaψ[CH2NH]-Phe-OMe (5), For-Met-NH-pC6H4-SO2-Phe-OMe (8a), For-Met-NH-mC6H4-SO2-Phe-OMe (8b) and the corresponding N-Boc precursors (2, 4, 7a, b) have been synthesized and their activity towards human neutrophils has been evaluated in comparison with that shown by the
reference tripeptide For-Met-Leu-Phe-OMe (fMLF-OMe). Chemotaxis, lysozyme release and superoxide anion production have been
measured. 1H NMR titration experiments and IR spectra have been discussed in order to ascertain the preferred solution conformation adopted
by the tripeptide 3 with particular reference to the presence of a folded conformation centred at the centrally positioned thionated β-residue. 相似文献
5.
The town of Carquefou, some 10 km northeast of Nantes on the left bank of the river Erdre, occupies a site long associated
with human activity. During road construction east of the town, ditches, enclosures and post holes characteristic of the late
la Tène were discovered at the locality of “Le Clouet”, which led us to obtain core samples from a nearby peat bog. These
investigations indicated the changes in vegetation since 3915±95 uncal B.P., [2828 (2459) 2074 cal B.C.]. The slopes in the
surroundings of the bog have been relatively treeless since the Bronze Age, but a very open woodland vegetation composed of
Tilia, Corylus and Quercus has been maintained until the present day. In the area around the bog, and Alnus wood with an undergrowth of Cyperaceae was the dominant vegetation, despite some changes probably related to human occupation
since the Bronze Age. Beginning at 955±35 uncal B.P. [1004 (1036, 1144, 1146) 1181 cal A.D.], in the Middle Ages, the alders
disappeared almost totally, apparently because of clearance or an increase in water level. Human presence led to intensified
cultivation of different crops including Cannabis and especially Cerealia. Finally, the presence of a variety of anthropogenic indicator plants (Cichorioideae, Asteraceae,
Plantago lanceolata, etc.) suggests that cattle were reared in the vicinity of the site.
Received May 22, 2000 / Accepted March 29, 2001 相似文献
6.
Summary. The effect of different doses of cadmium and copper was studied in relation to growth and polyamine (Pas) metabolism in shoots
of sunflower plants. Cadmium accumulated to higher levels than copper and shoot length was reduced by 0.5 and 1 mM Cd, but
only by 1 mM Cu. At 1 mM of Cd or Cu, Put content increased 270% and 160% with Cd2+ and Cu2+, respectively. Spermidine (Spd) was modified only by 1 mM Cd, while spermine (Spm) declined after seeds germinated, increasing
thereafter but only with 1 mM Cd or Cu (273% over the controls for Cd and 230% for Cu at day 16). Both ADC and ODC activities
were increased by 1 mM Cd, whereas 1 mM Cu enhanced ADC activity, but reduced ODC activity at every concentration used. The
role of Pas as markers of Cd or Cu toxicity is discussed. 相似文献
7.
The results of pollen analysis of two sediment cores from lake Srebarna (northeast Bulgaria) are presented. On the basis
of the palynological data and the radiocarbon dates a reconstruction of the past flora and vegetation is made. For the first
time a continuous palaeosuccession is established for the area of the Danubian Dobrudza and the Ludogorie district of northeast
Bulgaria: a dominance of mixed xero- and mesophilous oak woods with Carpinus betulus, Ulmus, Tilia, Corylus during the Atlantic period; mixed oak woods with increasing importance of Tilia, Ulmus, Acer and a considerable presence of Carpinus betulus and Fagus during the Sub-boreal period; degradation of the woodland vegetation and transition to secondary plant communities with Carpinus orientalis and herbs during the Sub-atlantic period.
Received January 5, 2001 / Accepted March 13, 2001 相似文献
8.
The roles of gibberellins, abscisic acid and phytochrome B in the vernalization response were investigated by combining mutations
causing defects in their biosynthesis and response with the Arabidopsis thaliana (L.) Heynh. fca-1 mutation. The fca-1 mutation confers a very late-flowering phenotype which can be reversed to wild-type flowering if the seedlings are vernalized.
Vernalization was unaffected in ga1-3, gai, abi1-1, abi2-1, abi3-1 and phyB-1 backgrounds, suggesting that gibberellin action mediated via GA1 and GAI, abscisic acid action mediated through ABI1 and ABI2, and phytochrome B, function independently of vernalization. However, the mutations did interact with fca-1 to change flowering time in the absence of vernalization. The abi1 fca-1 and abi2 fca-1 double mutants flowered earlier than fca-1 implying a role for abscisic acid in floral repression. Combination of ga1-3 or gai with fca-1 unexpectedly resulted in opposite interactions, with gai partially suppressing the late flowering of fca-1.
Received: 17 July 1999 / Accepted: 11 October 1999 相似文献
9.
Eating the evidence? Manduca sexta larvae can not disrupt specific jasmonate induction in Nicotiana attenuata by rapid consumption 总被引:2,自引:0,他引:2
As feeding by the tobacco specialist Manduca sexta L. is known to result in significantly higher jasmonate (JA) concentrations in Nicotiana plants than do mechanical simulations of the larval damage, we investigated whether M. sexta, which is known to rapidly consume large quantities of leaf material, can impair this “recognition” response by consuming
the leaf tissue before it can respond with amplified JA levels. We report that oral secretions (OS) from M. sexta, but not from the cabbage specialist Pieris rapae, amplified the wound-induced JA response of Nicotiana attenuata Torr. Ex Wats., regardless of larval diet, instar and molting stage, and were still active after boiling and when diluted
to 1/1000. The largest JA response occurred within 40 min in tissues adjacent to the OS application site. When 3 mm of leaf
tissue immediately adjacent to the OS application site was excised within 40 s, the signal that elicits JA amplification was
found to travel rapidly into the leaf, beyond the mandibular reach of the larvae. We conclude that M. sexta is not able to consume the evidence of feeding activity.
Received: 16 July 1999 / Accepted: 12 August 1999 相似文献
10.
Tomato (Lycopersicon esculentum Mill.) prosystemin in fusion with a viral signal peptide was expressed in Sf21 insect cell cultures after infection with recombinant baculoviruses. Prosystemin was purified from culture supernatants
and its identity was confirmed by N-terminal sequence and mass-spectral analyses. Recombinant prosystemin was found to be
equally active as compared to systemin in inducing the expression of wound-response genes in tomato plants. In cultured cells
of L. peruvianum, prosystemin elicited a rapid alkalinization of the growth medium. The timing and dose-dependence of the alkalinization response
were found to be identical for prosystemin and systemin, respectively. Prosystemin-triggered defense responses were inhibited
by a competitive antagonist of systemin activity, indicating that the systemin sequence within the primary structure of prosystemin
determines its activity.
Received: 30 August 1999 / Accepted: 6 December 1999 相似文献
11.
The influence of pre-industrial animal husbandry on the boreal forest in south-central Sweden has been studied by pollen
and charcoal analyses of peat profiles from two mires in the vicinity of a shieling site. The impact of farming on the local
vegetation development is demonstrated from cal. A. D. 1300–1500 in three ways: forest clearance and cultivation of cereals
at the local shieling site; alterations of hydrology and vegetation, such as an increase in Cyperaceae, at mires used for
hay production; changes in the composition in the surrounding forest, with decreasing proportions of Betula, Picea and boreo-nemoral broadleaved trees and a consequent increase in Pinus, due to grazing and a change of fire regime. Similar alterations to the forest vegetation are noted at other sites in central
and northern Sweden during the last thousand years, when the system of using shielings became more widespread. Hence, early
animal husbandry is demonstrated to have had a regional impact on the long-term boreal forest development, replacing the original
mixed deciduous-coniferous forest with Pinus dominated forest.
Received November 27, 2001 / Accepted June 20, 2002
Correspondence to: Marie Emanuelsson 相似文献
12.
Summary. Spore coat-associated alanine racemase of Bacillus subtilis, which converts L-alanine to D-alanine, that is, the germinant to the competitive inhibitor, to regulate spore germination
for survival of the organism under unfavorable growth conditions, was examined. The dormant spores, L-alanine-initiated germination
of which is inhibited by diphenylamine, were used to characterize the enzyme in the native form because of its unextractablility
from dormant spores. The presence of isozymes, Enz-I and Enz-II with Km for L-alanine of about 20 mM and 50 mM and optimum
activity at around 40°C and 65°C, respectively, was proposed. The enzymes were selectively used depending on the L-alanine
concentration and the temperature. The pH profiles of the activity (optimun at pH 9.0) and the stability (stable between pH
6–11 at 60°C) were similar, but Enz-II was more heat-stable than Enz-I and the denaturation curve demonstrated a two-domain
structure for Enz-II. Sensitivity to D-penicillamine, hydroxylamine and HgCl2 was similar between Enz-I and Enz-II, while that to D-cycloserine, L- and D-aminoethylphosphonic acid, monoiodoacetate and
N-ethylmaleimide was different; HgCl2 was the most effective inhibitor among these compounds.
Received December 13, 1999, Accepted January 11, 2000 相似文献
13.
Summary. The relationship between cellular glutathione (GSH), protein-SH levels, and lactate dehydrogenase (LDH), with respect to
the effect of polyamines on the cytoprotective ability of L-cysteine and L-methionine, the most important components in the
sulfur amino acid metabolic pathway, in carbon tetrachloride (CCl4)-induced toxicity in isolated rat hepatocytes was studied. CCl4 induced a LDH release and decreased cellular thiols and polyamines levels but treatment with L-cysteine and L-methionine
reversed these decreases. Treating with methylglyoxal bis-(guanylhydrazone), MGBG, an irreversible inhibitor of S-adenosylmethionine
decarboxylase, which is a key enzyme in spermidine and spermine biosynthesis, and therefore used to deplete cellular polyamines,
prevented the protective effect of L-cysteine and L-methionine, but the addition of exogenous polyamines inhibited the influence
of MGBG. These results suggest that the cytoprotective effect of L-cysteine and L-methionine in CCl4-induced toxicity were via maintenance of cellular polyamines, GSH and protein-SH concentrations and prevention of LDH leakage.
Received September 1, 1999, Accepted January 11, 2000 相似文献
14.
The relationship between albumin, other plasma proteins and variables, and age in the acute phase response after liver resection in man 总被引:2,自引:0,他引:2
Summary. A large series of plasma albumin (ALB, g/dl) and simultaneous blood and clinical measurements were prospectively performed
on 92 liver resection patients, and processed to assess the correlations between ALB, other plasma proteins, additional variables
and clinical events. The measurements were performed preoperatively and at postoperative day 1, 3 and 7 in all patients, and
subsequently only in those who developed complications or died. In patients who recovered normally ALB was 4.3 ± 0.4 g/dl
(mean ± SD) preoperatively, 3.7 ± 0.7 at day 1 and 3, and 3.9 ± 0.4 at day 7. In patients with complications its decrease
was more prolonged. In non-survivors it was 3.4 ± 0.4 preoperatively, 3.0 ± 0.4 at day 1, and then decreased further. Regression
analysis showed direct correlations between ALB and pseudo-cholinesterase (CHE, U/l, nv 5300-13000), cholesterol (CHOL, mg/dl),
iron binding capacity (IBC, mg/dl), prothrombin activity (PA, % of standard reference) and fibrinogen, an inverse correlation
with blood urea nitrogen (BUN, mg/dl) for any given creatinine level (CREAT, mg/dl), and weaker direct correlations with hematocrit,
other variables and dose of exogenous albumin. An inverse relationship found between ALB and age (AGE, years) became postoperatively
(POSTOP) also a function of outcome, showing larger age-related decreases in ALB associated with complications (COMPL: sepsis,
liver insufficiency) or death (DEATH). Main overall correlations: CHE = 287.4(2.014)ALB, r = 0.73; CHOL = 16.5(1.610)ALB (1.001)ALKPH, r = 0.71; IBC = 68.6(1.391)ALB, r = 0.64; PA = 13.8 + 16.0(ALB), r = 0.51; BUN = 21.3 + 20.2(CREAT) – 6.2(ALB), r = 0.91; ALB = 5.0–0.013(AGE) – {0.5 +
0.003(AGE)
COMPL
+ 0.012(AGE)
DEATH
}
POSTOP
, r = 0.74 [p < 0.001 for each regression and each coefficient; ALKPH = alkaline phosphatase, U/l, nv 98-279, independent
determinant of CHOL; discontinuous variables in italics label the change in regression slope or intercept associated with
the corresponding condition]. These results suggest that altered albumin synthesis (or altered synthesis unable to compensate
for albumin loss, catabolism or redistribution) is an important determinant of hypoalbuminemia after hepatectomy. The correlations
with age and postoperative outcome support the concept that hypoalbuminemia is a marker of pathophysiologic frailty associated
with increasing age, and amplified by the challenges of postoperative illness. 相似文献
15.
Inoculation and nitrate alter phytohormone levels in soybean roots: differences between a supernodulating mutant and the wild type 总被引:9,自引:0,他引:9
The levels of different cytokinins, indole-3-acetic acid (IAA) and abscisic acid (ABA) in roots of Glycine max [L.] Merr. cv. Bragg and its supernodulating mutant nts382 were compared for the first time. Forty-eight hours after inoculation with Bradyrhizobium, quantitative and qualitative differences were found in the root's endogenous hormone status between cultivar Bragg and the
mutant nts382. The six quantified cytokinins, ranking similarly in each genotype, were present at higher concentrations (30–196% on average
for isopentenyl adenosine and dihydrozeatin riboside, respectively) in mutant roots. By contrast, the ABA content was 2-fold
higher in Bragg, while the basal levels of IAA [0.53 μmol (g DW)−1, on average] were similar in both genotypes. In 1 mM NO3
−-fed Bragg roots 48 h post-inoculation, IAA, ABA and the cytokinins isopentenyl adenine, and isopentenyl adenosine quantitatively
increased with respect to uninoculated controls. However, only the two cytokinins increased in the mutant. High NO3
− (8 mM) markedly reduced root auxin concentration, and neither genotypic differences nor the inoculation-induced increase
in auxin concentration in Bragg was observed under these conditions. Cytokinins and ABA, on the other hand, were little affected
by 8 mM NO3
−. Root IAA/cytokinin and ABA/cytokinin ratios were always higher in Bragg relative to the mutant, and responded to inoculation
(mainly in Bragg) and nitrate (both genotypes). The overall results are consistent with the auxin-burst-control hypothesis
for the explanation of autoregulation and supernodulation in soybean. However, they are still inconclusive with respect to
the inhibitory effect of NO3
−.
Received: 16 April 1999 / Accepted: 13 December 1999 相似文献
16.
Holger Freund Hilary H. Birks H. J. B. Birks 《Vegetation History and Archaeobotany》2001,10(2):107-115
Betula fruits lacking their wings were recovered from the Gross Todtshorn borehole, Germany, covering the late Eemian interglacial,
the Early Weichselian, and the Weichselian pleniglacial. In order to identify them, a data-set of seven size and shape variables
was made from modern fruits of B. pubescens, B. pendula, B. nana, and B. humilis. These measurements were summarised by principal components analysis (PCA). The 140 measured fossil fruit-bodies were positioned
passively on the PCA plot and identified by comparison with the dimensional envelopes of the modern species. Tree birches
(B. pendula, B. pubescens) occurred in the Eemian and Early Weichselian interstadials, but not thereafter.B. nana was widespread during the intervening stadials and the Oerel interstadial. B. humilis occurred throughout the sequence, coexisting with tree birches in the Early Weichselian and with B. nana in the stadials. It usually grew on mire surfaces, in contrast to B. nana which mainly grew on mineral substrates. However, B. nana grew on peat with B. humilis in the pleniglacial Oerel interstadial, suggesting a more continental climate with cold winters. A modern analogue could
be near the Ural mountains. B. humilis is presently rare in central Europe, but during the Weichselian it was well established in northern Germany. The PCA has
enabled specific determination of the wingless Betula fruits, leading to vegetational and climatic reconstructions and contributing to the previously poorly known historical biogeography
of Betula humilis.
Received June 14, 2000 / Accepted January 2, 2001 相似文献
17.
Summary. General procedures of N-chloroacetylation of the representative 1-aminoalkylphosphonic acids (GlyP, AlaP, ValP, PglyP and PheP) are described. These 1-(N-chloroacetylamino)-alkylphosphonic acids were converted into the corresponding glycylphosphonodipeptides (Gly-AAP) and/or related N-alkylglycylphosphonodipeptides (MenGly-AAP) in the course of ammonolysis/aminolysis. Physico-chemical properties of synthesized 1-(N-chloroacetylamino)-alkylphosphonic acids and phosphonodipeptides are characterized.
Authors’ address: Z. H. Kudzin, Institute of Chemistry, University of Łódź, Narutowicza 68, Łódź 91-136, Poland 相似文献
18.
The ABA INSENSITIVE1 (ABI1) and ABI2 genes encode homologous type-2C protein phosphatases with redundant yet distinct functions in abscisic acid (ABA) responses.
Results from Northern blot analysis showed that ABA- and mannitol-inducible expression of the COR47 and COR78/LTI78/RD29A (COR78) genes was more impaired in the abi2 mutant of Arabidopsis thaliana (L.) Heynh than in the abi1 mutant. Furthermore, ABA-plus-mannitol treatments were additive towards COR47 gene expression; however, the ABA-deficient aba1 mutant showed reduced COR expression relative to the wild type in response to mannitol and ABA-plus-mannitol treatments.
These results support the notion that drought- and ABA-signalling pathways are separate yet overlapping. To facilitate quantitative
analysis of the genetic control of tissue-specific ABA- and desiccation-response pathways, we analyzed ABA- and mannitol-inducible
expression of a carrot (Daucus carota L.) Dc3 promoter:uidA (β-glucuronidase; GUS) chimaeric reporter (Dc3-GUS) in transgenic wild-type, ABA-deficient aba1, and ABA-insensitive abi1 and abi2 mutants. The Dc3 promoter directed ABA- and mannitol-inducible GUS expression in Arabidopsis guard cells and the two treatments were additive. The aba1, abi1, and abi2 mutant genotypes had reduced GUS expression in guard cells of cotyledons in response to mannitol, whereas abi1 and abi2 mutants were reduced in ABA-inducible GUS expression, consistent with overlapping ABA- and drought-response pathways. Quantitative
fluorometric GUS assays of leaf extracts showed that abi2 mutants responded less to exogenous ABA than did abi1 mutants, and abi2 mutants responded more to mannitol than did abi1 mutants. We conclude that Dc3-GUSArabidopsis is a tractable system in which to study tissue-specific ABA and drought signalling and suggest that ABI2 functions predominantly over ABI1 in COR78 and COR47 gene expression and guard-cell Dc3-GUS expression.
Received: 23 May 1999 / Accepted: 3 December 1999 相似文献
19.
The ectopic expression of knotted homologues has cytokinin-like effects on plant morphology. The functional relationship between knotted and cytokinins was investigated in cultures of leaf tissue established from tobacco (Nicotiana tabacum L. cv. Havana 425) plants transformed with the maize knotted1 (kn1) gene regulated by cauliflower mosaic virus 35S RNA expression signals. In contrast to leaf tissues of untransformed plants,
leaf tissues of kn1 transformants were capable of sustained, cytokinin-autotrophic growth on auxin-containing medium and resembled the tobacco
cytokinin-autotrophic mutants Hl-1 and Hl-2. The concentration of 18 cytokinins was measured in cultures initiated from leaves of three independent kn1 transformants and the Hl-1 and Hl-2 mutants. Although cytokinin contents were variable, the content of several cytokinins in Kn1, Hl-1 and Hl-2 tissue lines was at least 10-fold higher than that of wild-type tobacco tissues and in the range reported for other cytokinin-autotrophic
tobacco tissues. These results suggest that the cytokinin-autotrophic growth of Kn1 lines could result from elevated steady-state levels of cytokinins.
Received: 7 July 1999 / Accepted: 10 November 1999 相似文献
20.
Summary. Acetohydroxyacid synthase (AHAS) inhibitors interfere with branched-chain amino acid biosynthesis by inhibiting AHAS. Glyphosate
affects aromatic amino acid biosynthesis by inhibiting 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). Glufosinate inhibits
glutamine synthetase and blocks biosynthesis of glutamine. AHAS gene variants that confer tolerance to AHAS inhibitors have
been discovered in plants through selection or mutagenesis. Imidazolinone-tolerant crops have been commercialized based on
these AHAS gene variants. A modified maize EPSPS gene and CP4-EPSPS gene from Agrobacterium sp. have been used to transform plants for target-based tolerance to glyphosate. A gox gene isolated from Ochrobactrum anthropi has also been employed to encode glyphosate oxidoreductase to detoxify glyphosate in plants. Glyphosate-tolerant crops with
EPSPS transgene alone or both EPSPS and gox transgenes have been commercialized. Similarly, bar and pat genes isolated from Streptomyces hygroscopicus and S. viridochromogenes, respectively, have been inserted into plants to encode phosphinothricin N-acetyltransferase to detoxify glufosinate. Glufosinate-tolerant crops have been commercialized using one of these two transgenes. 相似文献