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1.
Lithospermum (Boraginaceae) comprises approximately 40 species in both the Old and New Worlds, with a center of diversity in the southwestern United States and Mexico. Using ten cpDNA regions, a phylogeny of Lithospermum and related taxa was reconstructed. Lithospermum (including New World and Old World species) and related New World members of Lithospermeae form a monophyletic group, with Macromeria, Onosmodium, Nomosa, Lasiarrhenum, and Psilolaemus nested among species of Lithospermum. New World Lithospermeae also is a monophyletic group, with Eurasian species of Lithospermum sister to this group. Because Lithospermum is not monophyletic without the inclusion of the other New World genera, species from these genera are transferred to Lithospermum, and appropriate nomenclatural changes are made. New combinations are Lithospermum album, Lithospermum barbigerum, Lithospermum dodrantale, Lithospermum exsertum, Lithospermum helleri, Lithospemum leonotis, Lithospermum notatum, Lithospermum oaxacanum, Lithospermum pinetorum, Lithospermum rosei, Lithospermum trinverium, and Lithospermum unicum; new names are Lithospermum chiapense, Lithospermum johnstonii, Lithospermum macromeria, Lithospermum onosmodium, Lithospermum rzedowskii, and Lithospermum turneri.  相似文献   

2.
The potential of Fusarium oxysporum var. cubense UAMH 9013 to perform steroid biotransformations was reinvestigated using single phase and pulse feed conditions. The following natural steroids served as substrates: dehydroepiandrosterone (1), pregnenolone (2), testosterone (3), progesterone (4), cortisone (5), prednisone (6), estrone (7) and sarsasapogenin (8). The results showed the possible presence of C-7 and C-15 hydroxylase enzymes. This hypothesis was explored using three synthetic androstanes: androstane-3,17-dione (9), androsta-4,6-diene-3,17-dione (10) and 3α,5α-cycloandrost-6-en-17-one (11). These fermentations of non-natural steroids showed that C-7 hydroxylation was as a result of that position being allylic. The evidence also pointed towards the presence of a C-15 hydroxylase enzyme.The eleven steroids were also fed to Exophialajeanselmei var. lecanii-corni UAMH 8783. The results showed that the fungus appears to have very active 5α and 14α-hydroxylase enzymes, and is also capable of carrying out allylic oxidations.Ceratocystis paradoxa UAMH 8784 was grown in the presence of the above-mentioned steroids. The results showed that monooxygenases which effect allylic hydroxylation and Baeyer–Villiger rearrangement were active. However, redox reactions predominated.  相似文献   

3.
Bis-Netropsins with the C-ends of their netropsin fragments tethered via tetra- or pentamethylene linkers and with Gly or L-Lys-Gly residues on their N-ends were synthesized. The footprinting technique was used to study the specificity of bis-netropsin binding to the specially constructed DNA fragments containing various clusters of A · T pairs. It was found that the linker length affects the binding of bis-netropsins, with the tetramethylene linker providing better protection than the pentamethylene linker. It was shown that the newly synthesized bis-netropsins bind tighter to the 5"-A 4 T 4-3" sequence, whereas the bis-netropsin with a linker between the netropsin N-ends binds better to 5"-T 4 A 4-3" sequences.  相似文献   

4.
5.
Genomic in situ hybridisation (GISH) and Southern genomic hybridisation were applied in order to gain further knowledge regarding generic delimitation of the genus Hystrix as well as to clarify the genomes of the Hystrix species H. patula, H. longearistata, H. coreana, H. duthiei and H. komarovii. The hybridisation intensity of different genomic probes was compared among the Hystrix species and with other Triticeae species. The Southern- and GISH results confirm that H. patula contains the StH genome and show that H. komarovii most likely has a variant of this StH genome. The other Hystrix species under study, i.e. H. longearistata, H. coreana and H. duthiei, contain an Ns basic genome, and most probably two variants of this basic genome, Ns 1 Ns 2 . The genus Hystrix is thus not a monophyletic group of species.  相似文献   

6.
One new Bolivian species (Borreria pazensis) and three new varieties (Borreria densiflora var.minima, Richardia, scabra var.chacoensis andStaelia virgata var.killeenii) are described and illustrated. The genusDiodella, with three species (D. apiculata comb. nov., D. radula comb. nov., andD. teres), is reported for the first time.Borreria limae, B. wunschmannii, B. scabiosoides var.scabiosoides, andB. scabiosoides var.anderssonii are also reported as new to Bolivia.  相似文献   

7.
Casimirella Hassler (1913) is accepted and Humirianthera Huber (1914) considered a synonym. Casimirella diversifolia and C. lanata from Brazil are described as new species. Casimirella ampla (Miers) based on Leretia ampla Miers, C. crispula (Howard) based on Humirianthera crispula Howard, and C. rupestris (Ducke) based on Humirianthera rupestris Ducke are new combinations.  相似文献   

8.
为了解苦槛蓝(Myoporum bontioides)的化学成分,采用色谱分离法从叶中分离得到11个化合物,分别鉴定为:5,7,3’-三羟基-4’-甲氧基黄酮(1)、3,5,7,4’-四羟基-3’-甲氧基黄酮(2)、5,7,4’-三羟基-3’,5’-二甲氧基黄酮(3)、木犀草素(4)、山奈酚(5)、鼠李黄素(6)、5,7-二羟基二氢黄酮(7)、7,4’-二羟基二氢黄酮(8)、5,7,3’,4’-四羟基二氢黄酮(9)、5-O-乙酰基-3,7,3’,4’-四羟基二氢黄酮(10)和7-甲氧基香橙素(11)。除化合物4、7、11之外,其他化合物均为首次从苦槛蓝叶中分离得到。菌丝生长速率法测试表明化合物4、7~9和11对荔枝霜疫霉菌具有较好的抑菌活性。  相似文献   

9.
James L. Luteyn 《Brittonia》2001,53(3):437-446
Satyria ventricosa andVaccinium monteverdense from Panama and Costa Rica, respectively, are described and illustrated.Gonocalyx megabracteolatus andVaccinium talamancense are new combinations. Relationships of the new species are discussed. Keys are provided for the entire genusGonocalyx, and forSatyria in Mesoamerica.
Resumen  Se describenSatyria ventricosa yVaccinium monteverdense de Panamá y Costa Rica, respectivamente, con sus ilustraciones. Se hace una nueva combinación deGonocalyx megabracteolatus yVaccinium talamancense. También se discuten las relaciones entre las nuevas especies. Se incluyen claves para el género completoGonocalyx y para el géneroSatyria en Mesoamérica.
  相似文献   

10.
Conformational properties of five neuropeptides belonging to the calliFMRF-amide series with the Xaa-Pro-Yaa-Gln-Asp-Phe-Met-Arg-Phe-NH2 homologous sequences were studied by the method of theoretical conformational analysis. Three members of these group [(1) (Xaa = Thr, Yaa = Gln), (2) (Xaa = Thr, Yaa = Ser), and (3) (Xaa = Yaa = Ser)] can stimulate the saliva secretion from the separated salivary gland of the Calliphora vomitoria fly, whereas two other calliFMRF-amides [(4) (Xaa = Lys, Yaa = Asn) and (5) (Xaa = Ala, Yaa = Gly)] are inactive in this biological test. Low-energy spatial structures of the studied compounds were determined by a conformational analysis. A comparison of the stable structures of the biologically active and inactive neuropeptides revealed a similarity in their conformational properties and allowed determination of the role of separate residues in the peptide folding. The calculations demonstrated that the C-terminal hexapeptide fragment identical in all the five peptides tends to form -helical structure, whereas the variable N-terminal tripeptide regions of calliFMRF-amides (1)–(5) form more conformationally flexible structures.  相似文献   

11.
To evaluate the phylogenetic relationships of species in Pseudoroegneria and related genera, the nuclear ribosomal internal transcribed spacer (ITS) sequences were analyzed for eighteen Pseudoroegneria (St), two Elytrigia (E e St), two Douglasdeweya (StP), three Lophopyrum (E e and E b ), three Agropyron (P), two Hordeum (H), two Australopyrum (W) and two Psathyrostachys (Ns) accessions. The main results were: (i) Pseudoroegneria gracillima, P. stipifolia, P. cognata and P. strigosa (2x) were in one clade, while P. libanotica, P. tauri and P. spicata (2x) were in the other clade, indicating there are the differentiations of St genome among diploid Pseudoroegneria species; (ii) P. geniculata ssp. scythica, P. geniculata ssp. pruinifera, Elytriga caespitosa and Et. caespitosa ssp. nodosa formed the E e St clade with 6-bp indel in ITS1 regions; and (iii) Douglasdeweya wangii, D. deweyi, Agropyron cristatum and A. puberulum comprised the P clade. It is unreasonable to treat P. geniculata ssp. scythica and P. geniculata ssp. pruinifera as the subspecies of P. geniculata, and they should be transferred to a new genus Trichopyrum, which consists of species with E e St genomes. It is also suggested that one of the diploid donor of D. wangii and D. deweyi is derived from Agropyron species, and it is reasonable to treat tetraploid species with StP genomes into Douglasdeweya.  相似文献   

12.
Petra Hoffmann 《Brittonia》2008,60(2):136-166
Heterosavia (Phyllanthaceae) is segregated from Savia (tribe Bridelieae), recognized at generic rank, and placed in tribe Phyllantheae. Floral, fruit, leaf anatomical, leaf venation, and pollen characters of the neotropical taxa previously united as Savia including Gonatogyne are discussed and illustrated. Keys to the three genera and to the species of Heterosavia are presented. Four species (all new combinations), Heterosavia bahamensis, H. erythroxyloides, H. laurifolia, and H. maculata, are recognized. The new combinations Heterosavia laurifolia var. intermedia and H. maculata var. clementis are proposed. The names Heterosavia, H. erythroxyloides, H. laurifolia, Savia clementis, S. clusiifolia, S. clusiifolia var. fallax, and S. longipes are lectotypified. Distribution maps and conservation assessments (IUCN ratings) of Heterosavia species and varieties are provided.  相似文献   

13.
Interspecific and intergeneric hybridizations were carried out to evaluate the genomic relationships among species of Hystrix Moench and to study the relationships between Hystrix species and Psathyrostachys huashanica Keng (2n=2x=14, Nsh). Meiotic pairing in hybrids of Hystrix duthiei ssp. duthiei × P. huashanica (2n=3x=21), Hystrix duthiei ssp. longearistata × P. huashanica (2n=3x=21) and H. patula × P. huashanica (2n=3x=21) averaged 5.18, 5.11 and 0.29 bivalents per cell, while H. patula × H. duthiei ssp. longearistata (2n=4x=28) averaged 25.36 univalents and 1.32 bivalents per cell, respectively. The results indicate that (i) H. duthiei ssp. duthiei and H. duthiei ssp. longearistata have one set of Ns genome from Psathyrostachys; (ii) H. patula has no Ns genome; (iii) genomes of H. duthiei ssp. duthiei and H. duthiei ssp. longearistata are non-homologous to those of H. patula. The genomic relationships between H. patula and other Hystrix species are also discussed.  相似文献   

14.
铁皮石斛内生真菌次生代谢产物研究   总被引:1,自引:0,他引:1  
为了解铁皮石斛(Dendrobium officinale)内生真菌Phyllosticta aristolochiicola的次生代谢产物,从该真菌中分离得到15个化合物,经波谱分析分别鉴定为N-methyl-2-pyrolidinone (1)、环-(甘氨酸-L-脯氨酸)(2)、环-(D-丙氨酸-L-脯氨酸)(3)、环-(L-缬氨酸-L-脯氨酸)(4)、环-(L-亮氨酸-L-脯氨酸)(5)、cyclo-(L-Leu-D-4-hydroxyprolinyl)(6)、环-(L-苯丙氨酸-L-脯氨酸)(7)、环-(L-苯丙氨酸-L-4-羟基脯氨酸)(8)、环-(L-酪氨酸-L-脯氨酸)(9)、环-(L-苯丙氨酸-L-亮氨酸)(10)、啤酒甾醇(11)、对羟基苯乙醇(12)、对羟基苯乙酸(13)、(2S,3R)-1-(4-羟基苯基)丁烷-2,3-二醇(14)和(2R,3S)-1-苯基丁烷-2,3-二醇(15)。采用MTS法检测抗肿瘤活性表明,化合物2、10和14对HL-60、A-549、SMMC-7721、MCF-7和SW-480细胞株具有一定的抑制活性。  相似文献   

15.
饶固  戴丹  张波  李玉 《微生物学通报》2021,48(10):3791-3798
[背景] 托光柄菇属(Volvopluteus)隶属于光柄菇科(Pluteaceae),目前世界上仅有4个种。[目的] 调查我国东北地区大型真菌资源。[方法] 采集大型真菌标本,对其形态进行详细的观察和描述,提取DNA,测定rDNA ITS序列,基于最大似然法和贝叶斯法构建系统发育树。[结果] 2019–2020年在吉林省延边朝鲜族自治州敦化市采集的标本中,有6份标本为密执安托光柄菇V.michiganensis,该种真菌此前未在我国发现。在系统发育分析中,采自我国的密执安托光柄菇V.michiganensis与该种的模式标本聚为一个分支。[结论] 密执安托光柄菇V.michiganensis为中国新记录种。  相似文献   

16.
The tribal name Bocageeae Endlicher is reestablished and the tribe is circumscribed on the basis of solitary internodal ebracteate pedicels that are articulated at the base, and pollen shed in polyads of eight or more grains. Septate anther locules, large pollen size, and seed appendages are prevalent in the tribe. Intectate pollen with free-standing columellae, rare in Annonaceae, occurs not only in the genusTrigynaea but also in some species ofBocagea andHornschuchia. As defined here, the Bocageeae include seven neotropical genera:Cymbopetalum, Porcelia, Bocagea, Cardiopetalum, Froesiodendron, Hornschuchia, andTrigynaea. The latter five genera are revised and the treatments include ten new species:Cardiopetalum plicatum, Froesiodendron urceocalyx, Hornschuchia lianarum, H. santosii, H. leptandra, Trigynaea cinnamomea, T. lanceipetala, T. triplinervis, T. lagaropoda, andT. axilliflora, all from tropical South America. A new combination,Froesiodendron longicuspe, changes the rank of that taxon from subspecies to species.Cardiopetalum surinamense is removed fromFroesiodendron and reassigned toCardiopetalum on the basis of its connate petals, dehiscent monocarps, and seeds with bilobed arils. A cladogram provides an explicit hypothesis of intergeneric relationships in the tribe. The new combinationOnychopetalum periquino, based onTrigynaea periquino, is made.  相似文献   

17.
Cariniana as previously circumscribed is a genus of 16 species restricted to neotropical forest habitats on well-drained sites. A phylogenetic analysis of the genus based on 33 morphological and anatomical characters was undertaken. The results show that Cariniana consists of two clades: the Allantoma/Cariniana decandra clade includes Allantoma lineata and seven species of actinomorphic-flowered Cariniana and is characterized by 5-merous flowers, carnose petals, incurved petal apex, scarcely lobed calyces, eucamptodromous secondary veins, dichotomizing venation, and poorly developed areolation; the C. legalis clade is made up of nine species and is characterized by an obliquely zygomorphic androecium, reticulate tertiary venation, and anomocytic stomata. The actinomorphic-flowered Cariniana are more closely related to the monotypic Allantoma lineata than they are to the species of the C. legalis clade. In order to reflect these relationships, Cariniana is divided into two genera: species in the C. legalis clade, which includes the generic type C. legalis, remain as Cariniana while species of Cariniana in the Allantoma/Cariniana decandra clade are transferred to Allantoma. The following new combinations are proposed: Allantoma decandra, A. integrifolia, A. kuhlmannii, A. pluriflora (a nomen novum for Cariniana multiflora because Allantoma multiflora is a synonym of Couratari multiflora), A. pachyantha, A. pauciramosa, and A. uaupensis.  相似文献   

18.
【目的】利用16S rRNA和rpoC1基因分子标记研究螺旋藻、节旋藻的系统发育关系,并对其区分能力进行比较。【方法】以84株螺旋藻、节旋藻为研究对象,对其进行16S rRNA、rpoC1基因序列的扩增、测序及分析,并对构建的系统发育树进行对比。【结果】rpoC1基因序列保守位点所占比例49.7%、平均G+C百分含量47.7%和序列相似度76%–100%明显低于16S rRNA基因序列的79.4%、55.6%和91%–100%,其变异程度高于16S rRNA基因;基于16S rRNA、rpoC1基因构建的系统发育NJ树拓扑结构基本一致,84株实验藻株分为2个属3个类群,其中仅F-351、F-904-2、F-1070和TJBC14-1藻株为螺旋藻,其余均为节旋藻;虽然2个基因都不能区分形态种和地理种,但rpoC1基因NJ树的置信度(100%)高于16S rRNA基因(99%),属内分群效果也明显优于16S rRNA基因。【结论】支持了螺旋藻、节旋藻为两个不同属的结论,且在属内分类时rpoC1基因比16S rRNA基因具有更高的区分度。  相似文献   

19.
【背景】壳聚糖是广泛存在于甲壳动物的一种多糖,具有广谱的抗真菌活性,但壳聚糖是否影响炭黑曲霉(Aspergillus carbonarius)和硫色镰刀菌(Fusarium sulphureum)生长和发育尚未见报道。【目的】明确不同浓度壳聚糖对A. carbonariusF. sulphureum生长和发育的影响。【方法】通过在PDA培养基中添加不同浓度壳聚糖,测定两种真菌的菌落直径、生物量和菌丝干重,观察产孢量、孢子萌发和芽管长度,比较抑菌的差异。【结果】壳聚糖处理可显著改变两种真菌的菌落形态,处理浓度越高菌落皱缩和变形越明显;壳聚糖还可以有效抑制两种真菌的菌落生长、菌丝干重和菌丝生物量,抑制效果呈明显的浓度依赖,对F. sulphureum的抑制效果更好。壳聚糖可抑制两种真菌的产孢量、孢子萌发和芽管伸长,处理浓度越高抑制效果越好,对F. sulphureum的抑制效果更为明显。壳聚糖对A. carbonariusF. sulphureumEC50值分别为0.12 mg/mL和0.075 mg/mL。【结论】壳聚糖可有效抑制A. carbonariusF. sulphureum的生长发育,抑制效果呈浓度依赖,F. sulphureum对壳聚糖更为敏感。  相似文献   

20.
The cerebrosides were first isolated by Thudicum in 1874 and the structures were established by Carteret al. in 1950 (for review, see [2]). In 1961 Shapiro and Flowers [3] reported the first total synthesis of a cerebroside1 (Fig. 1) which was identified with the natural sample, only through comparison of their i.r. data. In order to confirm the absolute configuration at C-2 of natural cerebroside1, we describe here an unambiguous synthesis of two stereoisomeric cerebrosides1 and2, and found that the1H-NMR spectra of the synthetic1 (Fig. 2) was completely identical with that of the natural cerebroside reported recently by Dabrowskiet al. [4].In planning the synthetic route, the target structures1 and2 were disconnected at the dotted lines to give three key synthetic intermediates3, 4 and5 or6 (Fig. 1).Abbreviations Bu butyl - Ph phenyl - t-BuPh2SiCl t-butyldiphenylsilyl chloride - MTPA -methoxy--trifluoromethylphenylacetic acid - THF tetrahydrofuran Part 36 in the series Synthetic Studies on Cell-surface Glycans, for part 35, see [1]  相似文献   

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