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1.
Seven sulfated polyhydroxysteroids were isolated from the Far East starfish Pteraster obscurus and the ophiura (snake star) Asteronyx loveni (collected in the Sea of Okhotsk) and characterized: disodium and sodium salts of (20R)-24-methyl-2β-hydroxycholesta-5,24(28)-diene-3α,21-diyl disulfate, (20R)-5α-cholestane-3β,21-diyl disulfate, (20R)-3β-hydroxy-5α-cholestan-21-yl sulfate, (20R)-cholest-5-ene-3β,21-diyl disulfate, (20R)-2β-hydroxycholest-5-ene-3α,21-diyl disulfate, (20R)-cholest-5-en-3β-yl sulfate, and (20R)-5α-cholestan-3β-yl sulfate. The first four compounds turned out to be new, whereas the others were identical to the known compounds. Structures of the isolated steroids were identified by two-dimensional NMR spectroscopy and other physicochemical methods. The compounds isolated from starfish are structurally similar to typical ophiuroid metabolites, which support the opinion of some taxonomists that starfish and ophiuroids are phylogenetically related classes.  相似文献   

2.
Two new steroid glycosides: distolasteroside D6, (24S)-24-O-(β-D-xylopyranosyl)-5α-cholestane-3β,6α,8,15β,16β,24-hexaol, and distolasteroside D7, (22E,24R)-24-O-(β-D-xylopyranosyl)-5α-cholest-22-ene-3β,6α,8,15β,24-pentaol were isolated along with the previously known distolasterosides D1, D2, and D3, echinasteroside C, and (25S)-5α-cholestane-3β4β,6α,7α,8,15α,16β,26-octaol from the Far Eastern starfish Distolasterias nipon. The structures of new compounds were elucidated by NMR spectroscopy and MALDI TOF mass spectrometry. Like neurotrophins, distolasterosides D1, D2, and D3 were shown to induce neuroblast differentiation in a mouse neuroblastoma C1300 cell culture.  相似文献   

3.
Three new steroid glycosides (evasteriosides C, D, and E) along with six known compounds were isolated from two Pacific starfish of the genus Evasterias. Evasterioside C from E. retiferacollected from the Sea of Japan was identified as (20R, 22E)-3-O-(β-D-xylopyranosyl)-24-nor-5α-cholest-22-ene-3β,6β,15α,26-pentaol 26-sulfate sodium salt. The structures of evasteriosides D and E from E. echinosoma (collected from the Gulf of Shelichov, the Sea of Okhotsk) were established as (20R, 24S)-24-O-(β-D-glucopyranosyl)-5α-cholestane-3β,6α,8,15β,24-pentaol and (20R,24S)-3,24-di-O-(β-D-xylopyranosyl)-cholest-4-ene-3β,6β,8,15α,24-pentaol, respectively. In addition, the known compounds pycnopodiosides A and C, luridoside A, 5α-cholestane-3β,6α,8,15β,16β,26-hexaol. 5α-Cholestane-3β,6α,8,15β,24-pentaol 24-sulfate sodium saltand marthasterone sulfate sodium salt were identified in E. echinosoma. The structures of the isolated compounds were established on the basis of spectroscopic analyses, using 1D and 2D NMR techniques, mass spectrometry, and some chemical transformations.  相似文献   

4.
Two new steroid glycosides from the starfish Fromia milleporella collected in the Seychelles were isolated and characterized: milleporoside A, (20R, 24R)-29-O-[3-O-methyl-β-D-xylopyranosyl-(1→4)-3-O-methyl-β-D-xylopyranosyl]-24-ethyl-5α-cholestane-3β,4β,6α,8,15β,16β,29-heptaol, and milleporoside B, (20R, 24R)-(22E)-28-O-[3-O-methyl-β-D-xylopyranosyl-(1→4)-3-O-methyl-β-D-xylopyranosyl]-24-methyl-5α-cholest-22-ene-3β,4β,6α,8,15β,16β,28-heptaol. The structures of the glycosides were determined from their spectra and a comparison with spectral characteristics of known compounds. These compounds exhibit a moderate cytostatic activity toward the embryos of the sea urchin Strongylocentrotus intermedius.  相似文献   

5.
Six new natural compounds were isolated from two Far Eastern starfish species, Henricia aspera and H. tumida, collected in the Sea of Okhotsk. Two new glycosylated steroid polyols were obtained from H. aspera: asperoside A and asperoside B, which were shown to be (20R,24R, 25S)-3-O-(2,3-di-O-methyl-β -D-xylopyranosyl)-24-methyl-5α-cholest-4-ene-3β, 6β,8,15α,16β,26-hexaol and (20R, 24R,25S,22E)-3-O-(2,4-di-O-methyl-β-D-xylopyranosyl)-24-methyl-5α-cholest-22-ene-3β,4β,6β,8,15α,26-hexaol, respectively. Two other glycosylated polyols, tumidoside A, with the structure elucidated as (20R, 22E)-3-O-(2,4-di-O-methyl-β -D-xylopyranosyl)-26,27-dinor-24-methyl-5α-cholest-22-ene-3β,4β,6β,8,15α,25-hexaol, and tumidoside B, whose structure was elucidated as (20R,24S)-3-O-(2,3-di-O-methyl-β-D-xylopyranosyl)-5α-cholestan-3β,4β,6β,8,15α,24-hexaol, were isolated from the two starfish species. (20R, 24S)-5α-Cholestan-3β,6β,15α,24-tetraol and (20R, 24S)-5α-cholestan-3β,6β,8,15α,24-pentaol were identified only in H. tumida. The known monoglycosides henricioside H1 and laeviuscolosides H and G were also identified in both species.  相似文献   

6.
Under laboratory conditions the development of the starfish Asterias amurensis Lütken from Vostok Bay (Sea of Japan) was studied at 14 and 17°C. At 14°C and a salinity of 31.6–32.6, ciliated coeloblastulae hatched from egg envelopes 19 h after fertilization. At this temperature the development proceeded slowly and stopped at the stage of bipinnaria. At 17°C and normal salinity of seawater, the development of A. amurensis was successful. The swimming blastula appeared in 14 h. It took 30.5 h for the embryos to reach the gastrula stage. The larvae began swimming in a horizontal position with the apical tip ahead. The dipleurula appeared at 60 h. These larvae began feeding. At 71 h after the beginning of development, the early bipinnaria has developed. In the larva, the edged ciliated band, the preoral plate, and the anal plate were already formed. At the age of 4.2 days, the larvae reached the stage of bipinnaria and the brachiolaria stage developed by 26–28 days after fertilization. The larvae had three identical brachiolar arms with attachment papillae on their tips and an attachment disk. In 37–44 days (at 17°C) the pelagic phase of A. amurensis development was completed by the attachment of larvae to the bottom plates and termination of metamorphosis. Most likely, the specificity to a substrate is not expressed in the brachiolaria of A. amurensis. They can settle on almost any hard substrate which is coated with a bacterial film. The newly settled juvenile starfish had five well-developed arms and moved using their ambulacral podia.Original Russian Text Copyright © 2005 by Biologiya Morya, Kashenko.  相似文献   

7.
The gene encoding sucrose phosphorylase (742sp) in Leuconostoc mesenteroides NRRL B-742 was cloned and expressed in Escherichia coli. The nucleotide sequence of the transformed 742sp comprised an ORF of 1,458 bp giving a protein with calculated molecular mass of 55.3 kDa. 742SPase contains a C-terminal amino acid sequence that is significantly different from those of other Leu. mesenteroides SPases. The purified 742SPase had a specific activity of 1.8 U/mg with a K m of 3 mM with sucrose as a substrate; optimum activity was at 37°C and pH 6.7. The purified 742SPase transferred the glucosyl moiety of sucrose to cytosine monophosphate (CMP). Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

8.
Two new species of Lirula (L. japonica and L. exigua) on Abies mariesii collected in subalpine areas of northern Japan are described as members of Rhytismatales, Discomycetes. Lirula japonica causes needle cast in fir, but L. exigua seems to occur on the needles of physically damaged twigs. Morphological characteristics of both species are discussed.  相似文献   

9.
This study reflects on the monophyly of, and species diversity within, the genus Pseudocercospora in Far East Asia. Morphological characteristics and phylogenetic analyses of Pseudocercospora species were based on type specimens and ex-type cultures, which were collected from Japan and Taiwan. A phylogenetic tree was generated from multi-locus DNA sequence data of the internal transcribed spacer regions of the nrDNA cistron (ITS), partial actin (actA), and partial translation elongation factor 1-alpha (tef1), as well as the partial DNA-directed RNA polymerase II second largest subunit (rpb2). Based on these results, Pseudocercospora amelanchieris on Amelanchier and Ps. iwakiensis on Ilex were newly described from Japan, and a further 22 types (incl. two neo-, five lecto-, and 15 epitypes), were designated. The genus Pseudocercospora as presently circumscribed was found to be monophyletic, while the secondary barcodes, actA, tef1, and rpb2 were shown to be well suited to delimitate species within the genus.  相似文献   

10.
11.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

12.
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.  相似文献   

13.
Thirteen steroidal compounds including three new polyhydroxysteroids, (24R,25S)-24-methyl-5α-cholestane-3β,6α,8,15β,16β,26-hexaol, (22E,24R,25S)-24-methyl-5α-cholest-22-ene-3β,6α,8,15β,16β,26-hexaol, and (22E,24R,25S)-24-methyl-5α-cholest-22-ene-3β,4β,6α,8,15β,16β,26-heptaol, have been isolated along with ten previously known polyhydroxysteroids from the tropical starfish Asteropsis carinifera collected near the coast of Vietnam. The structures of the new compounds were elucidated by spectroscopic methods (mainly 2D NMR and ESI mass spectrometry).  相似文献   

14.
Ogataea parapolymorpha sp. n. (NRRL YB-1982, CBS 12304, type strain), the ascosporic state of Candida parapolymorpha, is described. The species appears homothallic, assimilates methanol as is typical of most Ogataea species and forms hat-shaped ascospores in asci that become deliquescent. O. parapolymorpha is closely related to Ogataea angusta and Ogataea polymorpha. The three species can be resolved from gene sequence analyses but are unresolved from fermentation and growth reactions that are typically used for yeast identification. On the basis of multiple isolates, O. angusta is known only from California, USA, in association with Drosophila and Aulacigaster flies, O. parapolymorpha is predominantly associated with insect frass from trees in the eastern USA but O. polymorpha has been isolated from various substrates in the USA, Brazil, Spain and Costa Rica.  相似文献   

15.
Summary   Erythroxylum longisetulosum I. Loiola & M. F. Sales and E. timothei I. Loiola & M. F. Sales (sect. Rhabdophyllum) from north-eastern Brazil are described and illustrated, and their taxonomic and ecological relationships are discussed.  相似文献   

16.
A new Dactylella species, Dactylella alba was isolated from the ascospores of Orbilia alba collected in Wenshan County, Yunnan Province, China. Conidiophores were either not branched or occasionally branched, bearing divergent sterigmata on the tip with single conidium on each. Conidia were elongated ellipsoids, 1–2 septate, mostly 1 septate. By combining the ITS sequence with morphological characteristics, a new anamorphic species is described and illustrated together with its teleomorph.  相似文献   

17.
18.
Summary   Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed.  相似文献   

19.
Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.  相似文献   

20.
We describe the purification and chemical characterization of galactomannans that appear both in the biomass and the culture broth during surface-liquid culture of the fungus Clonostachys rosea, a common facultative saprophyte that has potential to be used as a biological control agent against several plant pathogenic fungi, insects and nematodes. The galactomannans from both sources had comparable ratios of Man, Gal and Glc and the similarity were confirmed by 1H, 13C NMR, HMQC, and COSY spectra. We propose that the galactomannan in the culture broth originates from autolysis of the biomass, based not only on the similarity that it has with the galactomannan extracted from the biomass but also on the fact that its concentration increased rapidly after glucose depletion from the medium, when biomass concentration was falling. Polysaccharides from C. rosea have not previously been characterized; we show that the characteristics of the galactomannans are consistent with those that have been reported for other members of the Bionectriaceae, the family to which C. rosea belongs.  相似文献   

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