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1.
A new natural product, 2(S),3(S)-3-hydroxy-4-methyleneglutamic acid (G3) has been isolated from seeds of Gleditsia caspica. The structure has been established by chemical and spectroscopic methods. Catalytic reduction of G3 yields 2(S),4(S)-4-methylglutamic acid and a new amino acid, 2(S),3(S),4(S)-3-hydroxy-4-methylglutamic acid. Ozonolysis of G3 followed by oxidation gives 2(S),3(R)-3-hydroxyaspartic acid. The S- (or l-) configurations at C2 in G3 and in 2(S),3(S),4(S)-3-hydroxy-4-methyglutamic acid and the S-configurations at C3 for G3 and 2(S),3(S),4(S)-3-hydroxy-4-methylglutamic acid and at C4 for 2(S),3(S),4(S)-3-hydroxy-4-methylglutamic acid are inferred from the configurations at C2 in 2(S),4(S)-4-methylglutamic acid and at C2 and C3 in 2(S),3(R)-3-hydroxyaspartic acid. The seeds also contain appreciable quantities of 2(S),3(S),4(R)-3-hydroxy-4-methylglutami c acid (G1) and 2(S),4(R)-4-methylglutamic acid.  相似文献   

2.
The following new cycloartanes were isolated from the aerial parts of Lindheimera texana: (16S,23S)- and (16S,23R)-16,23-epoxycycloart-24-en-3-one, (3S,16S,23S)- and (3S,16S,23R)-16,23-epoxycycloart-24-en-3ol, (16S,23R)-16,23-epoxy-23,25-epidioxycycloartan-3-one, (16S)-23,24,25,26,27-pentanorcycloartan-3-one-16,22-olide, (16S,23S,24R)- or (16S,23R,24S)-23,24-epoxycycloartan-3-one-16,25-diol and (16S,23ζ,24ζ)-cycloartan-3-one-16,23,24,25-tetrol. Structures were established by chemical transformations and spectroscopic methods and, in the case of (16S,23R)-16,23-epoxy-23,25-epidioxycycloartan-3-one, by X-ray crystallography. Norambreinolide, several known labdanes and oleanolic acid were also isolated.  相似文献   

3.
In this study, S-allele diversity of eight wild and two commercial species of the Cerasus subgenus in Iran was investigated using two primer pairs. A high level of S-allele polymorphism was detected among and within the species evaluated. Furthermore, most of wild species showed 2–4 alleles based on S-allele primers and may be considered as tetraploid. Sweet cherry cultivars, Siah-Mashhad, Siah-Shabestar, Takdaneh-Mashhad, Siah-Daneshkadeh and Protiva showed S3S12, S3S12, S3S12, S3S5 and S3S4 combinations, respectively, allele S3 showing the highest frequency. Three Iranian sweet cherry cultivars had the same allelic combination (S3S12) that the same ancestor in genealogy of these cultivars may explain the loss of diversity observed at the S-locus. Wild cherry (mazzard) accessions showed wide range of alleles such as S1, S2, S7, S14 and S20 and unknown alleles, while sour cherries showed S6, S9, S13 and S27 alleles. In conclusion, the conservation of these highly diverse native species of Iranian wild Cerasus germplasm is recommended for future breeding activity.  相似文献   

4.
Four abietane diterpenoids, inflexanin C, inflexanin D, inflexuside A and inflexuside B, were isolated from the aerial parts of Isodon inflexus. Their respective structures were established by NMR, mass spectrometry and CD as (+)-(1S,4R,5S,7S,8S,10S,13S)-1,7,18-trihydroxy-abieta-9(11)-ene-12-one 1-monoacetate, (+)-(1S,4R,5S,10S,13S)-1,18-dihydroxy-abieta-7,9(11)-diene-12-one 1-monoacetate, (−)-(1S,5S,10S,11R,13R)-1,11,13-trihydroxy-abieta-8-ene-7-one 1-O-β-d-glucopyranoside and (−)-(1S,5S,10S,11R,13R)-1,11,13-trihydroxy-abieta-8-ene-7-one 1-O-(2-O-coumaroyl)-β-d-glucopyranoside. All compounds showed strong inhibitory activity against nitric oxide (NO) production in RAW264.7 lipopolysaccaride (LPS)-activated macrophages.  相似文献   

5.

Key message

We report a rapid and reliable method for S genotyping of Rosaceae fruit trees, which would to be useful for successful planting of cross-compatible cultivars in orchards.

Abstract

Japanese plum (Prunus salicina) and sweet cherry (Prunus avium), belonging to the family Rosaceae, possess gametophytic self-incompatibility controlled by a single polymorphic locus containing at least two linked genes, S-RNase and SFB (S-haplotype-specific F-box gene). For successful planting of cross-compatible cultivars of Rosaceae fruit trees in commercial orchards, it is necessary to obtain information on S genotypes of cultivars. Recently, a method of dot-blot analysis utilizing allele-specific oligonucleotides having sequences of SFB-HVa region has been developed for identification of S haplotypes in Japanese plum and sweet cherry. However, dot-blot hybridization requires considerable time and skill for analysis even of a small number of plant samples. Thus, a quick and efficient method for S genotyping was developed in this study. In this method, instead of a nylon membrane used for dot-blot hybridization, streptavidin-coated magnetic beads are used to immobilize PCR products, which are hybridized with allele-specific oligonucleotide probes. Our improved method allowed us to identify 10 S haplotypes (S-a, S-b, S-c, S-d, S-e, S-f, Sh, S-k, S-7 and S-10) of 13 Japanese plum cultivars and 10 S haplotypes (S-1, S-2, S-3, S-4, S-4′, S-5, S-6, S-7, S-9 and S-16) of 13 sweet cherry cultivars utilizing SFB or S-RNase gene polymorphism. This method would be suitable for identification of S genotypes of a small number of plant samples.  相似文献   

6.
The nominative subgenus of Schizophoria (Brachiopoda, Orthida) is represented in the Lower and Middle Devonian of Poland and of the western Ukraine by six taxa: late Emsian Schizophoria (S.) interstrialis, late Eifelian S. (S.) schnuri biscissa, early Givetian S. (S.) schnuri schnuri, middle to late Givetian S. (S.) schnuri prohibita ssp.n., middle Givetian S. (S.) parvaepunctata and late Givetian S. (S.) sp.n. (unnamed for lack of sufficient material). Morphotypes referable to S. (S.) schnuri biscissa and to S. (S.) schnuri junkerbergiana co-occur in the same outcrop (not necessarily in the same levels), wherefore the separation of these subspecies may be maintained only if they are considered as chronosubspecies (unverifiable on the studied material) but not as geographic variants (hypothesis falsified by the studied material). A lectotype for S. (S.) interstrialis and a neotype for S. (S.) parvaepunctata are selected. Punctae diameter and density (either an important systematic character according to some authors or devoid of such value according to other ones) were investigated: they show important within-individual and within-sample variation, wherefore they cannot serve to distinguish related species. On the contrary, punctae character combinations are sufficiently constant to help differentiate subgenera or groups of species. In the studied material, three clusters are distinguished on the basis of the punctae characteristics: S. (Pachyschizophoria) and S. (S.) parvaepunctata differ between each other and from all other investigated species of S. (Schizophoria); the latter are indistinguishable on the sole basis of punctae characteristics.  相似文献   

7.
Self-incompatibility has been studied extensively at the molecular level in Solanaceae, Rosaceae, and Scrophulariaceae, all of which exhibit gametophytic self-incompatibility. In the present study, we successfully isolated nine S-RNase alleles from cultivars of Chinese cherry by PCR amplification from genomic DNA and stylar cDNA combining with cleaved amplified polymorphic sequence marker. Analysis of amino acid sequences revealed five novel S-alleles, S 2 , S 4 , S 6 , S 8 , and S 9 , with respective accession numbers in the NCBI database of EF541168, EF541173, EF541172, FJ628598, and FJ628599. Results showed that “Dongtang” and “Yinzhu” contained six S-alleles (S 1 , S 3 , S 5 , S 7 , S 8 , and S 9 ); “Taishanganying” contained four S-alleles (S 1 , S 2 , S 4 , and S 6 ); “Daiba”, “Dayingzui”, and “Xiaomizi” contained four S-alleles (S 1 , S 2 , S 5 , and S 8 ); “Laiyangduanzhi”, “Shuangquanchangba”, and “Daqingye” contained three S-alleles (S 1 , S 2 , and S 8 ). It is interesting that different cultivars collected from the same place hold the same S-genotypes. Moreover, pollination tests and pollen tube growth assays showed that nine cultivars were self-compatible. Chinese cherry presented in this article are naturally polyploidy, which is a very useful material for the study of self-compatibility, and much of this information will be valuable for further work on self-(in)compatibility of fruit tree in Rosaceae.  相似文献   

8.
Two isomers (R,S,R,S- and R,R,S,S-) of five coordinate complex [Cu(L)Cl]+ have been separated and characterised. These two isomers have significantly different spectrochemical and electrochemical properties. Absorption maximum of R,S,R,S-[Cu(L)Cl]+ shifts to longer wavelength and its reduction potential shifts to more positive direction comparing those of R,R,S,S-[Cu(L)Cl]+. R,S,R,S-[Cu(L)Cl]+ is significantly distorted to trigonal-bipyramidal structure, whereas R,R,S,S-[Cu(L)Cl]+ retains almost square-planar geometry. The average bond distance of Cu-N in basal plane of R,S,R,S-[Cu(L)Cl]+ is longer by 0.024 Å than that of R,R,S,S-[Cu(L)Cl]+, whereas the bond distance of Cu-Cl in former is shorter by 0.200 Å than that in latter. The isolated square-planar complexes of R,R,S,S- and R,S,R,S-[Cu(L)](ClO4)2 are converted to the R,R,S,S- and R,S,R,S-[Cu(L)Cl]+ by the addition of Cl in nitromethane solution with the rate constants, k=1.70 (±0.02) and 8.31 (±0.07) M−1 s−1, respectively.  相似文献   

9.
The highly polymorphic S (for self-incompatibility) locus regulates self-incompatibility in Petunia inflata; the S-RNase regulates pistil specificity, and multiple S-locus F-box (SLF) genes regulate pollen specificity. The collaborative non-self recognition model predicts that, for any S-haplotype, an unknown number of SLFs collectively recognize all non-self S-RNases to mediate their ubiquitination and degradation. Using a gain-of-function assay, we examined the relationships between S2-SLF1 (for S2-allelic product of Type-1 SLF) and four S-RNases. The results suggest that S2-SLF1 interacts with S7- and S13-RNases, and the previously identified S1- and S3-RNases, but not with S5- or S11-RNase. An artificial microRNA expressed by the S2-SLF1 promoter, but not by the vegetative cell-specific promoter, Late Anther Tomato 52, suppressed expression of S2-SLF1 in S2 pollen, suggesting that SLF1 is specific to the generative cell. The S2 pollen with S2-SLF1 suppressed was compatible with S3-, S5-, S7-, S11-, and S13-carrying pistils, confirming that other SLF proteins are responsible for detoxifying S5- and S11-RNases and suggesting that S2-SLF1 is not the only SLF in S2 pollen that interacts with S3-, S7-, and S13-RNases. Petunia may have evolved at least two types of SLF proteins to detoxify any non-self S-RNase to minimize the deleterious effects of mutation in any SLF.  相似文献   

10.
Self-incompatibility of sweet cherry (Prunus avium L.) is controlled by the multiallelic S-locus. While many cultivars and wild accessions have been S-genotyped, only limited data are available on accessions native to the center of origin of this species. Therefore, this study was carried out to determine the S-genotype of 11 landrace cultivars and 17 local genotypes selected from populations growing wild at the Black Sea coast. Eleven sweet cherries (S 1S 7, S 10, and S 12S 14) and some wild cherries (S 17S 19, S 21/25, and S 31) S-RNase alleles were detected. The results indicate that Turkish cultivars represent a broader gene pool as compared with international cultivars. A new (S 37) and a doubtful allele (provisionally labelled as S 7m) as well as the sour cherry S 34-allele were identified in sweet cherry. These data and others (SSR variants within the S 13-RNase introns) confirmed that allele pools of sweet and sour cherries in the Black Sea region are overlapping. A new cross-incompatibility group, XLV (S 2 S 18), was also proposed. Allele-specific primers were designed for S 17S 19, S 21/25, S 34, and S 37. A phylogenetic analysis of the cherry S 31-RNase and its trans-specific sister alleles reliably mirrored the assumed length of the time period after the divergence of species in the subgenera Cerasus and Prunophora. Most variations (insertions/deletions and single-nucleotide polymorphisms) in the S-RNase gene were silent and, hence, have not been exposed to natural selection. The results are discussed from the aspects of S-allele evolution and phylogenetic relationships among cherries and other Prunus species.  相似文献   

11.
The structures of three new 11-monomethoxy pentacyclic oxindole alkaloids have been elucidated by chemical correlations with reserpinine: caboxine-A was assigned to the allo C19-méthyl α series: 3S, 4R, 7S, 19S; isocaboxine-A and B to the epi-allo C19-methyl α series and have, respectively, the following configurations 3R, 4S, 7S, 19S and 3R, 4S, 7R, 19S.  相似文献   

12.
13.
The two main objectives of this research were to identify new S-RNase alleles in Iranian almond cultivars and to characterize naturally occurring mutations in these alleles that may cause self-compatibility. We investigated S genotypes of 22 Iranian almond cultivars using stylar RNase electrophoresis, PCR and DNA sequencing. We report six previously unidentified P. dulcis S-RNase alleles (S 45 , S 46 , S 47 , S 48 , S 49 and S 50 ). Four of 12 tested S-RNases were found to be non-functional in vitro: S 49 , S 50 , S 24 /S na and S 25 /S 47 . Detected point mutations in the C3 coding region of S 49 - and S 50 -RNase, leading to the replacement of a highly conserved cysteine and histidine residues, are with the highest probability the reason of these S-RNases inactivity. Results also suggested that ten Iranian almond cultivars display unique S genotype. All presented data confirm Iranian cultivars as valuable almond sources which are of interest to almond breeding and conservation programs.  相似文献   

14.
In GPIIb/IIIa mediated arterial thrombosis platelet activation plays a central role. To discover platelet activation inhibitor the pharmacophores of GPIIb/IIIa receptor inhibitors and anti-thrombotic agents were analyzed. This led to the design of (1R,3S)- and (1S,3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acids as GPIIb/IIIa inhibitors. Comparing to (1S,3S)-isomer (1R,3S)-isomer had lower cdocker interaction energy. AFM image showed that the minimal effective concentration of (1S,3S)-isomer and (1R,3S)-isomer inhibiting platelet activation were 10?5?M and 10?6?M, respectively. In vivo 1?μmol/kg of oral (1S,3S)-isomer effectively inhibited the rats to form arterial thrombus and down regulated GPIIb/IIIa expression, but the activities were significantly lower than those of 1?μmol/kg of oral (1R,3S)-isomer. Both (1S,3S)-isomer and (1R,3S)-isomer can be safely used for structural modifications, but (1R,3S)-isomer should be superior to (1S,3S)-isomer.  相似文献   

15.
Medium polarity fractions of the hexane extracts of the stems of Bursera suntui afforded six previously known (1-6) and four hitherto unknown verticillane derivatives: (1S,3Z,7S,8S,11S,12S)-(+)-7,8-epoxyverticill-3-en-12,20-diol (7), (1S,3Z,7S,8S,11S,12S)-(+)-7,8-epoxyverticill-3-en-12,20-diol 20-acetate (8), (1S,3Z,7S,11S,12S)-(+)-verticilla-3,8(19)-dien-7,12,20-triol (9), and (1S,3Z,7S,11S,12S)-(+)-verticilla-3,8(19)-dien-7,12,20-triol 20-acetate (10). Acetylation of 9 and 10 yielded (1S,3Z,7S,11S,12S)-(+)-verticilla-3,8(19)-dien-7,12,20-triol 7,20-diacetate (11), while hydrolysis of 8 gave 7. The structures and stereochemistry of 7-11 were established by spectroscopic analyses, particularly by 1D and 2D NMR spectra and HRESIMS. The conformational preferences of 7-11 were studied by molecular mechanics modelling employing the Monte Carlo protocol followed by B3LYP/DGDZVP DFT calculation, thus supporting the observed 1H NMR NOESY cross peaks.  相似文献   

16.
Three progenies of sour cherry (Prunus cerasus) were analysed to correlate self-(in)compatibility status with S-RNase phenotype in this allotetraploid hybrid of sweet and ground cherry. Self-(in)compatibility was assessed in the field and by monitoring pollen tube growth after selfing. The S-RNase phenotypes were determined by isoelectric focusing of stylar proteins and staining for RNase activity and, for the parents, confirmed by PCR. Seedling phenotypes were generally consistent with disomic segregation of S-RNase alleles. The genetic arrangements of the parents were deduced to be ‘Köröser’ (self-incompatible) S 1 S 4 .S B S D , ‘Schattenmorelle’ (self-compatible) S 6 S 13 .S B S B , and clone 43.87 (self-compatible) S 4 S 13 .S B S B , where “.” separates the two homoeologous genomes. The presence of S 4 and S 6 alleles at the same locus led to self-incompatibility, whereas S 13 and S B at homoeologous loci led to self-compatibility. The failure of certain heteroallelic genotypes in the three crosses or in the self-incompatible seedlings indicates that S 4 and S 6 are dominant to S B . However, the success of S 13 S B pollen on styles expressing corresponding S-RNases indicates competitive interaction or lack of pollen-S components. In general, the universal compatibility of S 13 S B pollen may explain the frequent occurrence of S 13 and S B together in sour cherry cultivars. Alleles S B and S D , that are presumed to derive from ground cherry, and S 13 , presumably from sweet cherry, were sequenced. Our findings contribute to an understanding of inheritance of self-(in)compatibility, facilitate screening of progenies for self-compatibility and provide a basis for studying molecular interactions in heteroallelic pollen.  相似文献   

17.
A benzene extract of the trunk of an Aniba species (Lauraceae) contained benzyl benzoate, benzyl salicylate, sitosterol and the neolignans (2S,3S,3aR)-3a-allyl-5-methoxy-3-methyl-2-piperonyl-2,3,3a,6-tetrahydro-6-oxobenzofuran (burchellin); (2S,3S,3aR)-3a-allyl-5-methoxy-3-methyl-2-veratryl-2,3,3a,6-tetrahydro-6-oxobenzofuran; (2S,3S,3aR)-3a-allyl-5,7-dimethoxy-3-methyl-2-veratryl-2,3,3a,6-tetrahydro-6-oxobenzofuran; (2S,3S,5S)-5-allyl-5-methoxy-3-methyl-2-veratryl-2,3,5,6-tetrahydro-6-oxo-benzofuran; (2R,3R)-7-methoxy-3-methyl-5-propenyl-2-veratryl-2,3-dihydrobenzofuran; rel-(1R,5R,6R,7R,8S)-1-allyl-8-hydroxy-3-methoxy-7-methyl-4-oxo-6-piperonylbicyclo[3,2,1]oct-2-ene (guianin); rel-(1S,5S,6S,7R,8R)-1-allyl-8-hydroxy-3,5-dimethoxy-7-methyl-4-oxo-6-piperonylbicyclo[3,2,1]oct-2-ene; rel-(1S,5S,6S,7R,8R)-8-acetoxy-1-allyl-3-hydroxy-5-methoxy-7-methyl-4-oxo-6-piperonyl-bicyclo[3,2,1]oct-2-ene; rel-1S,5S,6S,7R,8R)-8-acetoxy-3,5-dimethoxy-7-methyl-4-oxo-6-piperonylbicyclo[3,2,1]oct-2-ene; rel-(1R,5S,6R,7R)-1-allyl-3-methoxy-7-methyl-4,8-dioxo-6-piperonylbicyclo[3,2,1]oct-2-ene.  相似文献   

18.
Most cultivars of Japanese pear (Pyrus pyrifolia Nakai) exhibit gametophytic self-incompatibility controlled by a single S-locus with multiple S-haplotypes. A self-compatible (SC) cultivar, ??Osanijisseiki?? (S 2 S 4 sm ), arising by a bud mutation of ??Nijisseiki?? (S 2 S 4 ), has a stylar-part mutant S 4 sm -haplotype, which lacks the pistil S 4 gene, which is the S 4 -RNase gene. To efficiently breed SC cultivars, we selected ??Nashi Chuukanbohon Nou 1 Gou?? (??NCN1??) harboring homozygous S 4 sm from a self-progeny of Osanijisseiki and crossed it with ??Okusankichi?? (S 5 S 7 ), ??Hakkou?? (S 4 S 5 ), or ??Ri-14?? (S 1 S 2 ). Fruit set (%) was compared after self-pollination of the trees in the three progenies. All trees derived from the three progenies were predicted to be SC, except for the S 4 S 4 sm trees in the progeny of NCN1 × Hakkou. However, S 1 S 4 sm trees in the progeny of NCN1 × Ri-14 proved to be self-incompatible (SI). The pollen from Osanijisseiki was incompatible with ??Doitsu?? (S 1 S 2 ), but that from Nijisseiki was compatible, suggesting a possibility that the S 4 sm pollen was rejected by S 1 -harboring pistils. This possibility was clarified by crossing the pollen from NCN1 (S 4 sm S 4 sm ) to Doitsu, ??Imamuraaki?? (S 1 S 6 ), or ??Hougetsu?? (S 1 S 7 ), all of which proved incompatible. On the other hand, S 4 sm pollen was accepted by pistils harboring the S 2 , S 3 , S 5 , S 6 , S 7 , S 9 , and S k haplotypes. The dual recognition of S 1 and S 4 pistils by S 4 sm pollen can be attributed to a mutation of the pollen S 4 gene(s).  相似文献   

19.
Lipoxygenases (LOXs) biosynthesize lipid mediators (LMs) as human signaling molecules. Among LMs, specialized pro-resolving mediators (SPMs) are involved in the resolution of inflammation and infection in humans. Here, the putative LOX from the bacterium Sphingopyxis macrogoltabida was identified as arachidonate 9S-LOX. The enzyme catalyzed oxygenation at the n-12 position of C20 and C22 polyunsaturated fatty acids (PUFAs) to form 9S- and 11S-hydroperoxy fatty acids, which were reduced to 9S- and 11S-hydroxy fatty acids (HFAs) by cysteine, respectively, and it catalyzed again oxygenation at the n-6 position of HFAs to form 9S,15S- and 11S,17S-DiHFAs, respectively. The regioselective residues of 9S-LOX were determined as lle395 and Val569 based on the amino acid alignment and homology models. The regioselectivity of the I395F variant was changed from the n-12 position on C20 PUFA to the n-6 position to form 15S-HFAs. This may be due to the reduction of the substrate-binding pocket by replacing the smaller Ile with a larger Phe. The V569W variant had a significantly lower second?oxygenating activity compared to wild-type 9S-LOX because the insertion of the hydroxyl group of the first?oxygenating products at the active site was seemed to be hindered by substituting a larger Trp for a smaller Val. The compounds, 11S-hydroxydocosapentaenoic acid, 9S,15S-dihydroxyeicosatetraenoic acid, 9S,15S-dihydroxyeicosapentaenoic acid, 11S,17S-hydroxydocosapentaenoic acid, and 11S,17S-dihydroxydocosahexaenoic acid, were newly identified by polarimeter, LC-MS/MS, and NMR. 11S,17S-DiHFAs as SPM isomers biosynthesized from C22 PUFAs showed anti-inflammatory activities in mouse and human cells. Our study contributes may stimulate physiological studies by providing new LMs.  相似文献   

20.
Two new isodrimene sesquiterpene derivatives, 2(S)-hydroxyalbicanol (1, =(2S,4aS,8S,8aS)-8-(hydroxymethyl)-4,4,8a-trimethyl-7-methylenedecahydronaphthalen-2-ol) and 2(S)-hydroxyalbicanol 11-acetate (2, =((1S,4aS,7S,8aS)-7-hydroxy-5,5,8a-trimethyl-2-methylenedecahydronaphthalen-1-yl)methyl acetate) were isolated from the culture broth of the fungus Polyporus arcularius, together with two phenylpropanediols, (1S,2S)- and (1R,2S)-1-phenyl-1,2-dihydroxypropane (3, 4). Compound 3 is reported as a naturally occurring compound for the first time. The structures of the compounds were elucidated on the basis of spectroscopic analysis. Compound 1 exhibited growth inhibition of lettuce seedlings with IC50 values of 1.3 mM to hypocotyl and 1.7 mM to radicle.  相似文献   

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