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1.
From the aerial parts of Teucrium scordium a new neo-clerodane diterpenoid, 2-keto-19-hydroxyteuscordin, has been isolated, besides the previously known diterpenoids teucrin E and teucrin H4. The structure of 2-keto-19-hydroxyteuscordin, (12S)-15,16-epoxy-2-keto-19-hydroxy neo-clerodane-13(16),14-dien-18β,6β:20,12-diolide, was established by chemical and spectroscopic means.  相似文献   

2.
From the aerial part of Teucrium chamaedrys a new neo-clerodane diterpenoid, dihydroteugin, has been isolated, besides the previously known diterpenoids teucrin A and teugin. The structure of dihydroteugin, (12S)-15,16-epoxy-2β,6β-dihydroxy-neo-cleroda-13(16), 14-diene-18,19:20,12-diolide, was established by chemical and spectroscopic means and by partial synthesis from teugin.  相似文献   

3.
The previously proposed structure for teucrin B [15,16-epoxy -1,7-dihydroxy-cleroda-13(16),14-diene- 18,19:20,12-diolide] must be amended to 15,16-epoxy-2β,6β-dihydroxy-neo-cleroda-13(16), 14-diene-18,19:20,12S-diolide, which corresponds to the structure that has been established for dihydroteugin.  相似文献   

4.
Teucrium species, such as germander, are rich in neo-clerodane diterpenoids and have been used in traditional folk medicine for their stimulant, diuretic, antipyretic and antiseptic properties. However, the furano neo-clerodane diterpenoids present in germander have been implicated in the in vivo hepatotoxicity of this botanical. In this study, authenticated germander (Teucrium chamaedrys L. and Teucrium canadense L.) was used as the source material. Methanol extracts of powdered plant mate rial were prepared and analysed by HPLC using Synergi Max-RP columns with monitoring at 220 nm. Limited amounts of teucrin A and other diterpenoid standards were analysed on a Synergi Max-RP column in order to determine their retention times and to generate calibration curves. The same standards were subjected to concurrent mass spectral analysis. Teucrin A and diterpenoids such as dihydroteugin, teuflin, teuflidin and teucvidin were tentatively identified in the plant extracts by HPLC-MS and 1H-NMR experiments. For the isolation of teucrium diterpenoids on a semipreparative scale, a solid-phase extraction method was developed for the first time using styrene divinylbenzene and strata-X sorbents for teucrin A and teuflin, respectively. Semi-preparative HPLC of the methanol extract of the powdered aerial parts of Teucrium plants was carried out on a semipreparative Synergi Max-RP column with photodiode array detection in order to confirm the identities of some diterpenoids by HPLC-MS and NMR.  相似文献   

5.
We derive a new continuous free energy formula for protein folding. We obtain the formula first by adding hydrophobic effect to a classical free energy formula for cavities in water. We then obtain the same formula by geometrically pursuing the structure that fits best the well-known global geometric features of native structures of globular proteins: 1. high density; 2. small surface area; 3. hydrophobic core; 4. forming domains for long polypeptide chains. Conformations of a protein are presented as an all atom CPK model where each atom is a ball B(xi,ri). All conformations satisfy generally defined steric conditions. For each conformation P of a globular protein, there is a closed thermodynamic system ΩPP bounded by the molecular surface MP. Both methods derive the same free energy aV(P)+bA(P)+cW(P), where a,b,c>0, V(P), A(P), and W(P) are volume of ΩP, area of MP, and area of the hydrophobic surface WPMP, which quantifies hydrophobic effect.Minimizing W(P) is sufficient to produce statistically significant native like secondary structures and hydrogen bonds in the proteins we simulated.  相似文献   

6.
Campylobacter, Arcobacter, and Helicobacter species have been isolated from many vertebrate hosts, including birds, mammals, and reptiles. Multiple studies have focused on the prevalence of these Epsilonproteobacteria genera in avian and mammalian species. However, little focus has been given to the presence within reptiles, and their potential zoonotic and pathogenic roles. In this study, occurrence, diversity, and host association of intestinal Epsilonproteobacteria were determined for a large variety of reptiles. From 2011 to 2013, 444 cloacal swabs and fecal samples originating from 417 predominantly captive-held reptiles were screened for Epsilonproteobacteria. Campylobacter, Arcobacter, and Helicobacter genus specific PCRs were performed directly on all samples. All samples were also cultured on selective media and screened for the presence of Epsilonproteobacteria. Using a tiered approach of AFLP, atpA, and 16S rRNA sequencing, 432 Epsilonproteobacteria isolates were characterized at the species level. Based on PCR, Campylobacter, Arcobacter, and Helicobacter were detected in 69.3% of the reptiles; 82.5% of the chelonians, 63.8% of the lizards, and 58.0% of the snakes were positive for one or more of these genera. Epsilonproteobacteria were isolated from 22.1% of the reptiles and were isolated most frequently from chelonians (37.0%), followed by lizards (19.6%) and snakes (3.0%). The most commonly isolated taxa were Arcobacter butzleri, Arcobacter skirrowii, reptile-associated Campylobacter fetus subsp. testudinum, and a putative novel Campylobacter taxon. Furthermore, a clade of seven related putative novel Helicobacter taxa was isolated from lizards and chelonians. This study shows that reptiles carry various intestinal Epsilonproteobacteria taxa, including several putative novel taxa.  相似文献   

7.
A series of diunsaturated C18 esters (5c12c, 6c12c, 7c12c, 8c12c, 9c12c, 6c11c, 6c10c, 6c9c, 9c12t, 9t12c, 9t12t, 9c12a, 9a12c, 9t12a, 9a12t) has been converted to their monoepoxides and, except for the enyoates, to their diepoxides. The isomeric epoxyoctadecenoates produced from each dienoate are separated by TLC. Properties examined include TLC of the epoxy esters, GLC of the epoxy esters and of their bistrimethylsilyl and methyl trimethylsilyl ethers, the melting points of the derived dihydroxyoctadecenoates, and the reaction of methyl cis-6,7 cis-9,10- and cis-8,9, cis-12,13-diepoxyoctadecanoates with boron triflouride etherate.A new synthetic route to methyl 11-bromohendec-cis-9-enoate is reported.  相似文献   

8.
Various taxonomically useful profiles of four dehydrogenases (lactate, malate, glucose-6-phosphate, and a-glycerophosphate) and three hydrolases (acid and alkaline phosphatase and esterase) were detected in whole nematode homogenates of Meloidogyne javanica, M. hapla, M. incognita, M. arenaria, Ditylenchus dipsaci, D. triformis, Heterodera glycines, and Aphelenchus avenae. The enzyme profiles were stable in populations cultured on several different hosts. A tentative enzymically-determined phylogeny of Meloidogyne is given.  相似文献   

9.
Imino ligands have proven to be able to activate the trans geometry of platinum(II) complexes towards antitumor activity. These ligands, like aromatic N-donor heterocycles, have a planar shape but, different from the latter, have still an H atom on the coordinating nitrogen which can be involved in H-bond formation. Three classes of imino ligands have been extensively investigated: iminoethers (HN=C(R)OR′), ketimines (HN=CRR′), and amidines (HN=C(R)NR′R″). The promising efficacy of the platinum compounds with amidines (activity comparable to that of cisplatin for cis complexes and much greater than that of transplatin for trans complexes) prompted us to extend the investigation to amidine complexes with a bulkier organic residue (R = t-Bu). The tert-butyl group can confer greater affinity for lipophilic environments, thus potentiating the cellular uptake of the compound. In the present study we describe the synthesis and characterization of pivaloamidine complexes of platinum(II), (cis and trans-[PtCl2(NH3){Z-HN=C(t-Bu)NH2}] and cis and trans-[PtCl2{Z-HN=C(t-Bu)NH2}2]), platinum(III) ([Pt2Cl4{HN=C(t-Bu)NH}2(NH3)2]), and platinum(IV) (trans-[PtCl4(NH3){Z-HN=C(t-Bu)NH2}] and trans-[PtCl4{Z-HN=C(t-Bu)NH2}2]). The cytotoxicity of all new Pt complexes was tested toward a panel of cultured cancer cell lines, including cisplatin and multidrug resistant variants. In addition, cellular uptake and DNA binding, perturbations of cell cycle progression, induction of apoptosis, and p53 activation were investigated for the most promising compound trans-[PtCl2(NH3){Z-HN=C(t-Bu)NH2}]. Remarkably, the latter complex was able to overcome both acquired and intrinsic cisplatin resistance.  相似文献   

10.
Twenty-seven names are newly placed in synonymy, Plagiochila blepharophora (Nees) Lindenb. var. δ major Schiffn. (= P. sandei Dozy), P.boninensis Inoue (= P. fordiana Steph.), P. cadens Inoue (= P. sciophila Nees), P. cameronensis Inoue (= P. hampeana Gottsche), P. ceramica Inoue (= P. pulvinata Steph.), P. decidua Inoue & Grolle (= P. sciophila Nees), P. didyma Inoue (= P. parvifolia Lindenb.), P. euryphyllon Herzog (= P. sciophila Nees), P. flavovirens Steph. (= P. sciophila Nees), P. fraseri Steph. (= P. teysmannii Sande Lac), P. gedeana Schiffn. (= P. hampeana Gottsche), P. kaernbachii Steph. (= P. sandei Dozy), P. lagunensis Inoue (= P. junghuhniana Sande Lac), P. massalongoana Sande Lac. (= P. junghuhniana Sande Lac), P. minor Horik. (= P. fordiana Steph.), P. nilgherriensis Steph. (= P. semidecurrens (Lehm. & Lindenb.) Lindenb.), P. nubila Steph. (= P. sandei Dozy), P. nymanii Steph. (= P. sandei Dozy), P. orientalis Taylor (= P. sciophila Nees), P. seemannii Mitt. (= P. sandei Dozy), P. sepikensis Inoue (= P. inflata Steph.), P. spinosissima Steph. (= P. semidecurrens (Lehm. & Lindenb.) Lindenb.), P. subplanata Inoue (= P. sciophila Nees), P. trabeculata var. bifida S. Hatt. (= P. fordiana Steph.), P. trochantha Steph. (= P. sciophila Nees), P. tsutomui Inoue (= P. ungarangana Sande Lac), and P. wichurae Steph. (= P. renitens (Nees) Lindenb). Lectotypes are designated for P. junghuhniana, P. semidecurrens, and P. ungarangana. Plagiochila inflata Steph. is reinstated as a species of sect. Annotinae Carl.  相似文献   

11.
LapA RNAs, proteins, and activities increased in response to systemin, methyl jasmonate, abscisic acid (ABA), ethylene, water deficit, and salinity in tomato (Lycopersicon esculentum). Salicylic acid inhibited wound-induced increases of LapA RNAs. Experiments using the ABA-deficient flacca mutant indicated that ABA was essential for wound and systemin induction of LapA, and ABA and systemin acted synergistically to induce LapA gene expression. In contrast, pin2 (proteinase inhibitor 2) was not dependent on exogenous ABA. Whereas both LapA and le4 (L. esculentum dehydrin) were up-regulated by increases in ABA, salinity, and water deficit, only LapA was regulated by octadecanoid pathway signals. Comparison of LapA expression with that of the PR-1 (pathogenesis-related 1) and GluB (basic β-1,3-glucanase) genes indicated that these PR protein genes were modulated by a systemin-independent jasmonic acid-signaling pathway. These studies showed that at least four signaling pathways were utilized during tomato wound and defense responses. Analysis of the expression of a LapA1:GUS gene in transgenic plants indicated that the LapA1 promoter was active during floral and fruit development and was used during vegetative growth only in response to wounding, Pseudomonas syringae pv tomato infection, or wound signals. This comprehensive understanding of the regulation of LapA genes indicated that this regulatory program is distinct from the wound-induced pin2, ABA-responsive le4, and PR protein genes.  相似文献   

12.
The restriction sites of Autographa californica nuclear polyhedrosis virus (AcMNPV) E2 DNA were mapped for the endonucleases SmaI, KpnI, BamHI, SacI, XhoI, and EcoRI. The restriction maps of four other AcMNPV variants, Trichoplusia ni (TnMNPV), and Galleria mellonella (GmMNPV) genomes were determined and compared to the endonuclease cleavage maps of AcMNPV E2 DNA. The viral structural polypeptides of AcMNPV variants S3, E2, S1, M3, and R9 were the same when analyzed by polyacrylamide gel electrophoresis. The major structural polypeptides of GmMNPV and TnMNPV had the same pattern in polyacrylamide gels as did AcMNPV structural polypeptides. GmMNPV and TnMNPV had several minor structural protein differences as compared with AcMNPV. AcMNPV variants, TnMNPV, and GmMNPV were distinct but with very similar genomes and protein structures.  相似文献   

13.
Wong PP 《Plant physiology》1980,65(6):1049-1052
A quantitative method was developed to measure the binding of fluorescent-labeled lentil (Lens esculenta Moench), pea (Pisum sativum L.), broad bean (Vicia faba L.), and jackbean (Canavalia ensiformis L., DC.) lectins to various Rhizobium strains. Lentil lectin bound to three of the five Rhizobium leguminosarum strains tested. The number of lentil lectin molecules bound per R. leguminosarum 128C53 cell was 2.1 × 104. Lentil lectin also bound to R. japonicum 61A133. Pea and broad bean lectins bound to only two of the five strains of R. leguminosarum, whereas concanavalin A (jackbean lectin) bound to all strains of R. leguminosarum, R. phaseoli, R. japonicum, and R. sp. tested. Since these four lectins have similar sugarbinding properties but different physical properties, the variation in bindings of these lectins to various Rhizobium strains indicates that binding of lectin to Rhizobium is determined not only by the sugar specificity of the lectin but also by its physical characteristics.  相似文献   

14.
In searching for ethanol producing microorganisms also capable of fermenting pentoses, nine zygomycetes strains including three strains of Rhizopus oryzae, Mucor corticolous, M. hiemalis, M. indicus, Rhizomucor pusillus, R. miehei, and zygomycete IT were examined. Each strain was cultivated on glucose, xylose or dilute-acid hydrolyzate (DAH) as carbon sources, and the production of ethanol, lactic acid, glycerol, xylitol, and succinic acid were investigated. Great similarities but also conspicuous differences were seen between the species, to some extent linked to the genera. All strains were capable of growing on glucose or xylose as single carbon source. With the exception of the two Rhizomucor strains, all produced ethanol. All the strains produced glycerol as by-product, while Rhizopus and Rhizomucor but not Mucor produced lactic acid in significant amounts. All Mucor and Rhizopus strains and one strain of Rhizomucor produced xylitol in the xylose medium, but no xylitol was detected after growth on DAH. All Mucor and two R. oryzae strains were capable of growing on DAH. Two Mucor species, M. hiemalis and M. indicus showed greater ethanol production than the other strains. The ethanol yields by M. hiemalis on glucose, xylose, and DAH were 0.39, 0.18, and 0.44 g/g, respectively, whereas the corresponding results for M. indicus were 0.39, 0.22, and 0.44 g/g. The strains also rapidly consumed hydroxymethyl furfural present in DAH.  相似文献   

15.
16.
VanA-type human (n = 69), animal (n = 49), and food (n = 36) glycopeptide-resistant enterococci (GRE) from different geographic areas were investigated to study their possible reservoirs and transmission routes. Pulsed-field gel electrophoresis (PFGE) revealed two small genetically related clusters, M39 (n = 4) and M49 (n = 13), representing Enterococcus faecium isolates from animal and human feces and from clinical and fecal human samples. Multilocus sequence typing showed that both belonged to the epidemic lineage of CC17. purK allele analysis of 28 selected isolates revealed that type 1 was prevalent in human strains (8/11) and types 6 and 3 (14/15) were prevalent in poultry (animals and meat). One hundred and five of the 154 VanA GRE isolates, encompassing different species, origins, and PFGE types, were examined for Tn1546 type and location (plasmid or chromosome) and the incidence of virulence determinants. Hybridization of S1- and I-CeuI-digested total DNA revealed a plasmid location in 98% of the isolates. Human intestinal and animal E. faecium isolates bore large (>150 kb) vanA plasmids. Results of PCR-restriction fragment length polymorphism and sequencing showed the presence of prototype Tn1546 in 80% of strains and the G-to-T mutation at position 8234 in three human intestinal and two pork E. faecium isolates. There were no significant associations (P > 0.5) between Tn1546 type and GRE source or enterococcal species. Virulence determinants were detected in all reservoirs but were significantly more frequent (P < 0.02) among clinical strains. Multiple determinants were found in clinical and meat Enterococcus faecalis isolates. The presence of indistinguishable vanA elements (mostly plasmid borne) and virulence determinants in different species and PFGE-diverse populations in the presence of host-specific purK housekeeping genes suggested that all GRE might be potential reservoirs of resistance determinants and virulence traits transferable to human-adapted clusters.  相似文献   

17.
We describe 11 new species of Thaumatomonadida using light and electron microscopy and rDNA gene sequences (18S, ITS1, 5.8S, ITS2). We found clear distinctions between major clades in molecular and morphological traits that support now splitting Thaumatomastix into three genera: new marine genera Ovaloplaca (oval plate-scales) and Thaumatospina (triangular plate-scales), both with distinctive radially-symmetric bobbin-based spine-scales, restricting Thaumatomastix to freshwater species with putatively non-homologous eccentric-spine scales and thicker triangular plate-scales. New genus Scutellomonas lacks spine-scales, having oval plate-scales with deeply-dished upper tier as in Ovaloplaca, with which it forms a clade having short/absent anterior cilium. Cowlomonas gen. n. is possibly naked. We describe two new Allas species, two new Thaumatomonas, and one new Reckertia species, and transfer R. hindoni to Thaumatomonas. Triangular-scaled Reckertia has varied plate-scales and ciliary scales. Thaumatomonas rDNA trees reveal two clades: zhukovi/seravini (predominantly triangular scales); coloniensis/oxoniensis/lauterborni/constricta/solis (scales mostly oval). We hypothesise that the ancestor of Thaumatomonadidae had radially-symmetric bobbin-based spine-scales and triangular plate-scales, bobbin-based spine-scales being lost in one lineage and eccentric-spine scales evolving in Thaumatomastix. Bobbin-based spine-scales arguably evolved from triangular plate-scales and single-tier ciliary scales (Ovaloplaca and Reckertia only) from plate-scale rudiments. We present a unified scheme for scale evolution and development in Imbricatea.  相似文献   

18.
Kipling Will 《ZooKeys》2015,(545):131-137
Taxonomic changes are made for several problematic Australian Carabidae in the tribes Harpalini, Abacetini, Pterostichini, and Oodini. Examination of types resulted in the synonymy of Veradia Castelnau, 1867 with Leconomerus Chaudoir, 1850; Nelidus Chaudoir, 1878, Feronista Moore, 1965, and Australomasoreus Baehr, 2007 with Cerabilia Castelnau, 1867; and newly combining Fouquetius variabilis Straneo, 1960 in the genus Pediomorphus Chaudoir, 1878; Australomasoreus monteithi Baehr, 2007 in the genus Cerabilia Castelnau, 1867; and Anatrichis lilliputana W.J. Macleay, 1888 in the genus Nanodiodes Bousquet, 1996. Cuneipectus Sloane, 1907 is placed in Pterostichini Bonelli, 1810, which is a senior synonym of Cuneipectini Sloane, 1907.  相似文献   

19.
20.
The type status is described for 65 taxa of the Orthalicoidea, classified within the families Megaspiridae (14), Orthalicidae (30), and Simpulopsidae (20); one taxon is considered a nomen inquirendum. Lectotypes are designated for the following taxa: Helix brephoides d’Orbigny, 1835; Simpulopsis cumingi Pfeiffer, 1861; Bulimulus (Protoglyptus) dejectus Fulton, 1907; Bulimus iris Pfeiffer, 1853. The type status of Bulimus salteri Sowerby III, 1890, and Strophocheilus (Eurytus) subirroratus da Costa, 1898 is now changed to lectotype according Art. 74.6 ICZN. The taxa Bulimus loxostomus Pfeiffer, 1853, Bulimus marmatensis Pfeiffer, 1855, Bulimus meobambensis Pfeiffer, 1855, and Orthalicus powissianus var. niveus Preston 1909 are now figured for the first time. The following taxa are now considered junior subjective synonyms: Bulimus marmatensis Pfeiffer, 1855 = Helix (Cochlogena) citrinovitrea Moricand, 1836; Vermiculatus Breure, 1978 = Bocourtia Rochebrune, 1882. New combinations are: Kuschelenia (Bocourtia) Rochebrune, 1882; Kuschelenia (Bocourtia) aequatoria (Pfeiffer, 1853); Kuschelenia (Bocourtia) anthisanensis (Pfeiffer, 1853); Kuschelenia (Bocourtia) aquila (Reeve, 1848); Kuschelenia (Bocourtia) badia (Sowerby I, 1835); Kuschelenia (Bocourtia) bicolor (Sowerby I, 1835); Kuschelenia (Bocourtia) caliginosa (Reeve, 1849); Kuschelenia (Bocourtia) coagulata (Reeve, 1849); Kuschelenia (Bocourtia) cotopaxiensis (Pfeiffer, 1853); Kuschelenia (Bocourtia) filaris (Pfeiffer, 1853); Kara indentata (da Costa, 1901); Clathrorthalicus magnificus (Pfeiffer, 1848); Simpulopsis (Eudioptus) marmartensis (Pfeiffer, 1855); Kuschelenia (Bocourtia) nucina (Reeve, 1850); Kuschelenia (Bocourtia) ochracea (Morelet, 1863); Kuschelenia (Bocourtia) peaki (Breure, 1978); Kuschelenia (Bocourtia) petiti (Pfeiffer, 1846); Clathrorthalicus phoebus (Pfeiffer, 1863); Kuschelenia (Bocourtia) polymorpha (d’Orbigny, 1835); Scholvienia porphyria (Pfeiffer, 1847); Kuschelenia (Bocourtia) purpurata (Reeve, 1849); Kuschelenia (Bocourtia) quechuarum Crawford, 1939; Quechua salteri (Sowerby III, 1890); Kuschelenia (Bocourtia) subfasciata Pfeiffer, 1853; Clathrorthalicus victor (Pfeiffer, 1854). In an addedum a lectotype is being designated for Bulimulus (Drymaeus) interruptus var. pallidus Preston, 1909. An index is included to all taxa mentioned in this paper and the preceding ones in this series (Breure and Ablett 2011, 2012, 2014).  相似文献   

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