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Tasawan Keawwangchai Banchob Wanno Nongnit Morakot Somchai Keawwangchai 《Journal of molecular modeling》2013,19(10):4239-4249
Two BODIPY derivatives for Cu2+ ion chemosensors containing 4-[2-(diethylamino)-2-oxoethoxy]phenyl (BDP1) and 3,4-bis[2-(diethylamino)-2-oxoethoxy]phenyl (BDP2) were synthesized by coupling appropriate N,N-diethyl-2-(4-formylphenoxy)acetamide and 2,4-dimethylpyrrole moieties in the presence of trifluoroacetic acid and anhydrous dichloromethane at room temperature. The binding abilities between these chemosensors and 50 equivalents of Na+, K+, Ag+, Ca2+, Fe2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+ and Pb2+ ions were studied using UV-vis and fluorescence spectrophotometry. The results show that, compared to other ions, both the UV-vis absorption and fluorescence emission intensity of BDP2 decreased dramatically when Cu2+ ion was added. To explain this behavior, ab initio quantum chemical calculations were performed using correlated second-order Møller-Plesset perturbation theory (MP2/LanL2DZ). The calculated orbital energies indicated that the decrease in UV-vis absorption intensity and the quenching of fluorescene emission were due to the single-electron reduction of Cu2+ to Cu+ ion. Figure
Optimized structure, fluorescent spectra, frontier orbital energy diagrams and electron-transfer paths in receptor BDP2 before and after attachment to Cu2+ ion 相似文献
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Albino midrib 1, encoding a putative potassium efflux antiporter,affects chloroplast development and drought tolerance in rice 总被引:2,自引:0,他引:2
Peike Sheng Junjie Tan Mingna Jin Fuqing Wu Kunneng Zhou Weiwei Ma Yueqin Heng Jiulin Wang Xiuping Guo Xin Zhang Zhijun Cheng Linglong Liu Chunming Wang Xuanming Liu Jianmin Wan 《Plant cell reports》2014,33(9):1581-1594
Key message
Mutation of the AM1 gene causes an albino midrib phenotype and enhances tolerance to drought in riceAbstract
K+ efflux antiporter (KEA) genes encode putative potassium efflux antiporters that are mainly located in plastid-containing organisms, ranging from lower green algae to higher flowering plants. However, little genetic evidence has been provided on the functions of KEA in chloroplast development. In this study, we isolated a rice mutant, albino midrib 1 (am1), with green- and white-variegation in the first few leaves, and albino midrib phenotype in older tissues. We found that AM1 encoded a putative KEA in chloroplast. AM1 was highly expressed in leaves, while lowly in roots. Chloroplast gene expression and proteins accumulation were affected during chlorophyll biosynthesis and photosynthesis in am1 mutants. Interestingly, AM1 was induced by salt and PEG, and am1 showed enhanced sensitivity to salinity in seed germination and increased tolerance to drought. Taken together, we concluded that KEAs were involved in chloroplast development and played important roles in drought tolerance. 相似文献5.
As presently known, the genusSiphonoglossa can be divided into two “subgenera,” one of which is here divided into two sections,Pentaloba andSiphonoglossa. Two new species are described from a locality in Durango, Mexico :S. durangensis in sect.Siphonoglossa andS. linearifolia in sect.Pentaloba. Three other species are transferred intoSiphonoglossa:S. canbyi from northeastern Mexico;S. buchii from Haiti and the Dominican Republic andS. incerta from southern Baja California, Mexico. 相似文献
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William J. Percey Lana Shabala Michael C. Breadmore Rosanne M. Guijt Jayakumar Bose Sergey Shabala 《Planta》2014,240(4):729-743
Main conclusion
Salt stress reduces the ability of mesophyll tissue to respond to light. Potassium outward rectifying channels are responsible for 84 % of Na + induced potassium efflux from mesophyll cells. Modulation in ion transport of broad bean (Vicia faba L.) mesophyll to light under increased apoplastic salinity stress was investigated using vibrating ion-selective microelectrodes (the MIFE technique). Increased apoplastic Na+ significantly affected mesophyll cells ability to respond to light by modulating ion transport across their membranes. Elevated apoplastic Na+ also induced a significant K+ efflux from mesophyll tissue. This efflux was mediated predominately by potassium outward rectifying channels (84 %) and the remainder of the efflux was through non-selective cation channels. NaCl treatment resulted in a reduction in photosystem II efficiency in a dose- and time-dependent manner. In particular, reductions in Fv′/Fm′ were linked to K+ homeostasis in the mesophyll tissue. Increased apoplastic Na+ concentrations induced vanadate-sensitive net H+ efflux, presumably mediated by the plasma membrane H+-ATPase. It is concluded that the observed pump’s activation is essential for the maintenance of membrane potential and ion homeostasis in the cytoplasm of mesophyll under salt stress. 相似文献7.
Two intestinal bacterial strains MT4s-5 and MT42 involved in the degradation of (?)-epigallocatechin (EGC) were isolated from rat feces. Strain MT4s-5 was tentatively identified as Adlercreutzia equolifaciens. This strain converted EGC into not only 1-(3, 4, 5-trihydroxyphenyl)-3-(2, 4, 6-trihydroxyphenyl)propan-2-ol (1), but also 1-(3, 5-dihydroxyphenyl)-3-(2, 4, 6-trihydroxyphenyl)propan-2-ol (2), and 4′-dehydroxylated EGC (7). Type strain (JCM 9979) of Eggerthella lenta was also found to convert EGC into 1. Strain MT42 was identified as Flavonifractor plautii and converted 1 into 4-hydroxy-5-(3, 4, 5-trihydroxyphenyl)valeric acid (3) and 5-(3, 4, 5-trihydroxyphenyl)-γ-valerolactone (4) simultaneously. Strain MT42 also converted 2 into 4-hydroxy-5-(3, 5-dihydroxyphenyl)valeric acid (5), and 5-(3, 5-dihydroxyphenyl)-γ-valerolactone (6). Furthermore, F. plautii strains ATCC 29863 and ATCC 49531 were found to catalyze the same reactions as strain MT42. Interestingly, formation of 2 from EGC by strain MT4s-5 occurred rapidly in the presence of hydrogen supplied by syntrophic bacteria. Strain JCM 9979 also formed 2 in the presence of the hydrogen or formate. Strain MT4s-5 converted 1, 3, and 4 to 2, 5, and 6, respectively, and the conversion was stimulated by hydrogen, whereas strain JCM 9979 could catalyze the conversion only in the presence of hydrogen or formate. On the basis of the above results together with previous reports, the principal metabolic pathway of EGC and EGCg by catechin-degrading bacteria in gut tract is proposed. 相似文献
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John C. Semple 《Brittonia》1987,39(3):379-386
The following new names and combinations are proposed:Heterotheca barbata (Rydb.) Semple,H. horrida subsp.cinerascens (S. F. Blake) Semple,H. fulcrata vararizonica Semple,H. fulcrata var.senilis (Wooton & Standley) Semple,H. oregona var.compacta (Keck) Semple,H. oregona var.rudis (Greene) Semple,H. oregona var.scaberrima (A. Gray) Semple,H. pumila (Greene) Semple,H. villosa var.pedunculata (Greene) V. Harms ex Semple, andH. zionensis Semple. The following chromosome numbers are reported for the first time:H. fulcrata var.arizonica, 2n=9 II ;H. horrida subsp.cinerascens, 2n=18 II ;H. pumila, 2n=9 II ,2n=18 II ;H. zionensis, 2n=9 II . 相似文献
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Michael S Avidan Ben J Palanca David Glick Eric Jacobsohn Alex Villafranca Michael O'Connor George A Mashour 《BMC anesthesiology》2009,9(1):1-11
Background
Sevoflurane has been demonstrated to vasodilate the foeto-placental vasculature. We aimed to determine the contribution of modulation of potassium and calcium channel function to the vasodilatory effect of sevoflurane in isolated human chorionic plate arterial rings.Methods
Quadruplicate ex vivo human chorionic plate arterial rings were used in all studies. Series 1 and 2 examined the role of the K+ channel in sevoflurane-mediated vasodilation. Separate experiments examined whether tetraethylammonium, which blocks large conductance calcium activated K+ (KCa++) channels (Series 1A+B) or glibenclamide, which blocks the ATP sensitive K+ (KATP) channel (Series 2), modulated sevoflurane-mediated vasodilation. Series 3 – 5 examined the role of the Ca++ channel in sevoflurane induced vasodilation. Separate experiments examined whether verapamil, which blocks the sarcolemmal voltage-operated Ca++ channel (Series 3), SK&F 96365 an inhibitor of sarcolemmal voltage-independent Ca++ channels (Series 4A+B), or ryanodine an inhibitor of the sarcoplasmic reticulum Ca++ channel (Series 5A+B), modulated sevoflurane-mediated vasodilation.Results
Sevoflurane produced dose dependent vasodilatation of chorionic plate arterial rings in all studies. Prior blockade of the KCa++ and KATP channels augmented the vasodilator effects of sevoflurane. Furthermore, exposure of rings to sevoflurane in advance of TEA occluded the effects of TEA. Taken together, these findings suggest that sevoflurane blocks K+ channels. Blockade of the voltage-operated Ca++channels inhibited the vasodilator effects of sevoflurane. In contrast, blockade of the voltage-independent and sarcoplasmic reticulum Ca++channels did not alter sevoflurane vasodilation.Conclusion
Sevoflurane appears to block chorionic arterial KCa++ and KATP channels. Sevoflurane also blocks voltage-operated calcium channels, and exerts a net vasodilatory effect in the in vitro foeto-placental circulation. 相似文献10.
Wing-Yee Liu Jin-Ho Kang Hyeon-Seok Jeong Hye-Jeong Choi Hee-Bum Yang Ki-Taek Kim Doil Choi Gyung Ja Choi Molly Jahn Byoung-Cheorl Kang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(11):2503-2513
Key message
Bulked segregant analysis (BSA) using Affymetrix GeneChips revealed candidate genes underlying the major QTL for Phytophthora capsici resistance in Capsicum . Using the candidate genes, reliable markers for Phytophthora resistance were developed and validated.Abstract
Phytophthora capsici L. is one of the most destructive pathogens of pepper (Capsicum spp.). Resistance of pepper against P. capsici is controlled by quantitative trait loci (QTL), including a major QTL on chromosome 5 that is the predominant contributor to resistance. Here, to maximize the effect of this QTL and study its underlying genes, an F2 population and recombinant inbred lines were inoculated with P. capsici strain JHAI1-7 zoospores at a low concentration (3 × 103/mL). Resistance phenotype segregation ratios for the populations fit a 3:1 and 1:1 (resistant:susceptible) segregation model, respectively, consistent with a single dominant gene model. Bulked segregant analysis (BSA) using Affymetrix GeneChips revealed a single position polymorphism (SPP) marker mapping to the major QTL. When this SPP marker (Phyto5SAR) together with other SNP markers located on chromosome 5 was used to confirm the position of the major QTL, Phyto5SAR showed the highest LOD value at the QTL. A scaffold sequence (scaffold194) containing Phyto5SAR was identified from the C. annuum genome database. The scaffold contained two putative NBS-LRR genes and one SAR 8.2A gene as candidates for contributing to P. capsici resistance. Markers linked to these genes were developed and validated by testing 100 F1 commercial cultivars. Among the markers, Phyto5NBS1 showed about 90 % accuracy in predicting resistance phenotypes to a low-virulence P. capsici isolate. These results suggest that Phyto5NBS1 is a reliable marker for P. capsici resistance and can be used for identification of a gene(s) underlying the major QTL on chromosome 5. 相似文献11.
Cu(I)-mediated [3+2]cycloaddition between azides and alkynes has evolved into a valuable bioconjugation tool in radiopharmaceutical chemistry. We have developed a simple, convenient and reliable radiosynthesis of 4-[18F]fluoro-N-methyl-N-(propyl-2-yn-1-yl)benzenesulfonamide ([ 18 F]F-SA) as a novel aromatic sulfonamide-based click chemistry building block. [ 18 F]F-SA could be prepared in a remotely controlled synthesis unit in 32 ± 5 % decay-corrected radiochemical yield in a total synthesis time of 80 min. The determined lipophilicity of [ 18 F]F-SA (logP = 1.7) allows handling of the radiotracer in aqueous solutions. The versatility of [ 18 F]F-SA as click chemistry building block was demonstrated by the labeling of a model peptide (phosphopeptide), protein (HSA), and oligonucleotide (L-RNA). The obtained radiochemical yields were 77 % (phosphopeptide), 55–60 % (HSA), and 25 % (L-RNA), respectively. Despite the recent emergence of a multitude of highly innovative novel bioconjugation methods for 18F labeling of biopolymers, Cu(I)-mediated click chemistry with [ 18 F]F-SA represents a reliable, robust and efficient radiolabeling technique for peptides, proteins, and oligonucleotides with the short-lived positron emitter 18F. 相似文献
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Key message
Both in vitro and in vivo hairy root transformation systems could not replace whole plant transformation for promoter analysis of root-specific and low-P induced genes in soybean.Abstract
An efficient genetic transformation system is crucial for promoter analysis in plants. Agrobacterium-mediated transformation is the most popular method to produce transgenic hairy roots or plants. In the present study, first, we compared the two different Agrobacterium rhizogenes-mediated hairy root transformation methods using either constitutive CaMV35S or the promoters of root-preferential genes, GmEXPB2 and GmPAP21, in soybean, and found the efficiency of in vitro hairy root transformation was significantly higher than that of in vivo transformation. We compared Agrobacterium rhizogenes-mediated hairy root and Agrobacterium tumefaciens-mediated whole plant transformation systems. The results showed that low-phosphorous (P) inducible GmEXPB2 and GmPAP21 promoters could not induce the increased expression of the GUS reporter gene under low P stress in both in vivo and in vitro transgenic hairy roots. Conversely, GUS activity of GmPAP21 promoter was significantly higher at low P than high P in whole plant transformation. Therefore, both in vitro and in vivo hairy root transformation systems could not replace whole plant transformation for promoter analysis of root-specific and low-P induced genes in soybean. 相似文献14.
Rupert C. Barneby 《Brittonia》1985,37(1):85-87
Acacia guilandinae DC. is recognized asMimosa guilandinae (DC.) Barneby, endemic to French Guiana and adjoining Amapá, Brazil;M. pseudo-obovata is subordinated as a Brazilian var.pseudo-obovata (Taub.) Barneby to CaribbeanM. ceratonia L.; andM. laticifera is found synonymous withM. obovata Benth. Diagnostic morphological characters of each taxon are presented in key form. 相似文献
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Paul A. Fryxell 《Brittonia》1971,23(3):231-237
Dendrosida, here described as new, comprises three taxa:D. batesii Fryxell,D. sharpiana (Miranda) Fryxell ssp.sharpiana, andD. sharpiana ssp.occidentalis Fryxell. The genus is interpreted as a primitive representative of the tribe Malveae, and its relationship to other genera of theAbutilon alliance is discussed. An analysis of mericarp morphology in relation to seed dissemination mechanisms indicates that theAbutilon alliance may be divided into an Abutiloid and a Sidoid group.Dendrosida is included in the latter. 相似文献
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Density functional theory (DFT) was used to investigate the nickel- or nickel(0)/zinc- catalyzed decarbonylative addition of phthalic anhydrides to alkynes. All intermediates and transition states were optimized completely at the B3LYP/6-31+G(d,p) level. Calculated results indicated that the decarbonylative addition of phthalic anhydrides to alkynes was exergonic, and the total free energy released was ?87.6 kJ mol?1. In the five-coordinated complexes M4a and M4b, the insertion reaction of alkynes into the Ni-C bond occurred prior to that into the Ni-O bond. The nickel(0)/zinc-catalyzed decarbonylative addition was much more dominant than the nickel-catalyzed one in whole catalytic decarbonylative addition. The reaction channel CA→M1'→T1'→M2'→T2'→M3a'→M4a'→T3a1'→M5a1' →T4a1'→M6a'→P was the most favorable among all reaction pathways of the nickel- or nickel(0)/zinc- catalyzed decarbonylative addition of phthalic anhydrides to alkynes. And the alkyne insertion reaction was the rate-determining step for this channel. The additive ZnCl2 had a significant effect, and it might change greatly the electron and geometry structures of those intermediates and transition states. On the whole, the solvent effect decreased the free energy barriers. Figure
DFT study suggests that NiL4/ZnCl2 (L=PMe3) has higher catalysis than NiL4 in the synthesis of isocoumarin from phthalic anhydrides and alkynes. 相似文献
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Satish Kumar Yadava Kumar Paritosh Priya Panjabi-Massand Vibha Gupta Atika Chandra Y. S. Sodhi Akshay K. Pradhan Deepak Pental 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(11):2359-2369
Key message
Genetic locus for tetralocular ovary ( tet - o ) in Brassica rapa was identified and it was shown that the number of locules and width of silique are associated.Abstract
Brassica rapa is a highly polymorphic species containing many vegetables and oleiferous types. An interesting group of oleiferous types is the yellow sarson group (subspecies trilocularis) grown mostly in eastern India. This group contains lines that have bilocular ovaries, a defining trait of Brassicaceae, but also lines that have tetralocular ovaries. Yellow sarson lines commonly have high silique width which is further enhanced in the tetralocular types. We mapped the locus influencing tetralocular ovary in B. rapa using three mapping populations (F2, F6 and F7) derived from a cross between Chiifu (subspecies pekinensis, having bilocular ovary) and Tetralocular (having tetralocular ovary). QTL mapping of silique width was undertaken using the three mapping populations and a F2 population derived from a cross between Chiifu and YSPB-24 (a bilocular line belonging to yellow sarson group). Qualitative mapping of the trait governing locule number (tet-o) in B. rapa mapped the locus to linkage group A4. QTL mapping for silique width detected a major QTL on LG A4, co-mapping with the tet-o locus in bilocular/tetralocular cross. This QTL was not detected in the bilocular/bilocular cross. Saturation mapping of the tet-o region with SNP markers identified Bra034340, a homologue of CLAVATA3 of Arabidopsis thaliana, as the candidate gene for locule number. A C → T transition at position 176 of the coding sequence of Bra034340 revealed co-segregation with the tetralocular phenotype. The study of silique related traits is of interest both for understanding evolution under artificial selection and for breeding of cultivated Brassica species. 相似文献19.
Kadanthottu Sebastian Joseph Hosakatte Niranjana Murthy Kundapura Venkataramana Ravishankar 《Trees - Structure and Function》2014,28(6):1645-1651