New Alkaloid and Aromatic Glucoside from the Flowers of Cymbidium Lunagrad Eternal Green.

In this paper, we investigated the chemical components of the flowers of Lunagrad Eternal Green for the first time. In the whole post-fertilization, a new alkaloid, named Lunagrad A (), and a new aromatic glucoside, named Lunagrad B (), were isolated from the MeOH extract of the flowers of Lunagrad Eternal Green, along with other six known aromatic compounds (-) and three flavone glucosides (-). These structures were determined on the basis of NMR experiments, as well as chemical evidence.

rRNA Pseudogenes in Filamentous Ascomycetes as Revealed by Genome Data.

The nuclear ribosomal DNA (rDNA) is considered as a paradigm of concerted evolution. Components of the rDNA tandem repeats (45S) are widely used in phylogenetic studies of different organisms and the internal transcribed spacer (ITS) region was recently selected as a fungal DNA bar code. However, rRNA pseudogenes, as one kind of escape from concerted evolution, were reported in a wide range of organisms, especially in plants and animals.

Rice grassy stunt virus nonstructural protein p5 serves as a viral suppressor of RNA silencing and interacts with nonstructural protein p3.

Rice grassy stunt virus (RGSV), a member of the genus Tenuivirus, causes serious rice disease in Southeast Asian countries. In this study, a green fluorescent protein (GFP)-based transient expression assay was conducted to show that p5, encoded on RNA5 in the viral sense, is a viral suppressor of RNA silencing (VSR). Protein-protein interactions (PPIs) between p5 and all RGSV proteins except pC1 and pC2 were investigated using Gal4-based yeast two-hybrid (Y2H) experiments.

Complete genome sequence of a novel monopartite geminivirus identified in mulberry (Morus alba L.).

The genome sequence of a novel geminivirus from mulberry samples exhibiting crinkle leaf symptoms is reported. The sequence consisted of 2952 nt, containing four open reading frames (ORFs) in the viral-sense strand and two ORFs in the complementary-sense strand. The size of the genome and the conserved origin of replication are similar to those of members of the family Geminiviridae, but the genomic organization, number of ORFs, and especially five contiguous GAAAAA repeats positioned upstream of ORF1 distinguish it from other geminiviruses.

Plant antifungal proteins and their applications in agriculture.

Fungi are far more complex organisms than viruses or bacteria and can develop numerous diseases in plants that cause loss of a substantial portion of the crop every year. Plants have developed various mechanisms to defend themselves against these fungi which include the production of low-molecular-weight secondary metabolites and proteins and peptides with antifungal activity. In this review, families of plant antifungal proteins (AFPs) including defensins, lectins, and several others will be summarized.

[Construction of rice stripe virus NS2 and NS3 Co-RNAi transgenic rice and disease-resistance analysis].

NS2 and NS3 are two post-transcriptional gene silencing suppressors that are encoded by Rice stripe virus. Gene silencing suppressors are always related to the pathogenicity of viruses. In this study, the cDNA of NS2 and NS3 were recombined by overlapping PCR assays, ligated to the RNAi vector, and inserted into the PXQ expression vector using Pst I; the expressed vector was transferred into calluses induced from seeds of the japonica rice cultivar, 'Nipponbare', using an Agrobacterium-mediated method.

The complete chloroplast genome sequence of Anoectochilus roxburghii.

The complete chloroplast sequence of the Anoectochilus roxburghii, a popular traditional Chinese medicine for the treatment of cancer, was determined in this study. The chloroplast genome (cpDNA)^ was 152,802 bp in length, containing a pair of inverted repeats of 52,728 bp separated by a large single-copy region and a small single-copy region of 82,641 bp and 17,433 bp, respectively. The chloroplast genome encodes 116 predicted functional genes, including 81 protein-coding genes, four ribosomal RNA genes, and 31 transfer RNA genes, 25 of which are duplicated in the inverted repeat regions.

A new nepovirus identified in mulberry (Morus alba L.) in China.

An isometric virus was identified in mulberry leaves showing symptoms of mulberry mosaic leaf roll (MMLR) disease. Its genome consists of two (+)ssRNAs. RNA1 and RNA2 have 7183 and 3742 nucleotides, excluding the 3'-terminal poly(A) tail.

Five new taraxerene-type triterpenes from the branch barks of Davidia involucrata.

Five new taraxerene-type triterpenes, 2-nor-D-friedoolean-14-en-28-ol (1), 2-nor-d-friedoolean-14-en-3α,28-diol (2), 6α-hydroxy-2-nor-D-friedoolean-14-en-3,21-dione (3), 6α,11α,29-trihydroxy-D-friedoolean-14-en-3,16,21-trione (4), and 6α,23,29-trihydroxy-D-friedoolean-14-en-3,16,21-trione (5), were isolated from the MeOH extract of the branch barks of Davidia involucrata, together with five known compounds. Their structures were elucidated by means of various spectroscopic analyses. Five of the identified compounds showed moderate cytotoxicities against the cell proliferation of SGC-7901, MCF-7, and BEL-7404.

Complete genome sequence of narcissus late season yellows virus infecting Chinese narcissus in China.

The complete genome sequence of a Chinese narcissus isolate of narcissus late season yellows virus from Zhangzhou, China (NLSYV-ZZ), was determined to be 9,651 nucleotides in length, excluding the 3'-terminal poly (A) tail, by amplification and sequencing of virus RNA. The viral genome contains a single long open reading frame of 9,315 nucleotides encoding a polyprotein of 3,105 amino acids. The polyprotein was predicted to be cleaved into ten mature proteins by three viral proteases.

A new seco-neolignan glycoside from the root bark of Ailanthus altissima.

A new seco-neolignan glycoside, seco-dehydrodiconiferyl alcohol-4-O-β-D-glucopyranoside, together with eight known compounds, were obtained from the EtOH extract of the root bark of Ailanthus altissima. Their structures were elucidated based on the spectroscopic data. Three neolignan glycosides including 7,9,9'-trihydroxy-3,3',5'-trimethoxy-8-O-4'-neolignan-4-O-β-D-glucopyranoside, sonchifolignan B and citrusin B exhibited moderate in vitro inhibitory effect on tobacco mosaic virus replication with IC₅₀ values 0.

Protein from red cabbage (Brassica oleracea) seeds with antifungal, antibacterial, and anticancer activities.

A 30 kDa antifungal protein was purified from red cabbage ( Brassica oleracea ) seeds. It exhibited a molecular mass and N-terminal amino acid sequence disinct from those of previously isolated Brassica antifungal proteins. The protocol used entailed ion exchange chromatography on Q-Sepharose and SP-Sepharose followed by fast protein liquid chromatography on Mono S.

Expression of rice gall dwarf virus outer coat protein gene (S8) in insect cells.

To obtain the P8 protein of Rice gall dwarf virus (RGDV) with biological activity, its outer coat protein gene S8 was expressed in Spodoptera frugiperda (Sf9) insect cells using the baculovirus expression system. The S8 gene was subcloned into the pFastBac™1 vector, to produce the recombinant baculovirus transfer vector pFB-S8. After transformation, pFB-S8 was introduced into the competent cells (E.

Identification and expression of caspase-1 gene under heat stress in insecticide-susceptible and -resistant Plutella xylostella (Lepidoptera: Plutellidae).

A caspase gene in Plutella xylostella (DBM) was identified firstly and named Px-caspase-1. It had a full-length of 1172 bp and contained 900 bp open reading frame that encoded 300 amino acids with 33.6 kDa.

A new phenolic glycoside and cytotoxic constituents from Celosia argentea.

A new phenolic glycoside, 4-O-β-D-apifuranosyl-(1→2)-β-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone (2) and 11 known compounds were isolated from the MeOH extract of the plant Celosia argentea. The structures of the compounds were elucidated on the basis of spectroscopic analysis and chemical methods. Among the isolated compounds, stigmasterol (10) showed moderate inhibitory activities against SGC-7901 and BEL-7404 cells.

Constituents from the seeds of Brucea javanica with inhibitory activity of Tobacco mosaic virus.

Three new constituents were obtained along with 10 known compounds from the seeds of Brucea javanica. The structures of these compounds were determined based on spectral and chemical evidence. These new compounds included a monoterpenoid glycoside and two sesquiterpenes.

Coleus blumei viroid 6: a new tentative member of the genus Coleviroid derived from natural genome shuffling.

Coleus blumei can be infected by several viroids of the genus Coleviroid. One year after detecting a mixed infection of coleus blumei viroid 1 (CbVd-1) and 5 (CbVd-5) in coleus seedlings inoculated with these two viroids, we found an additional viroid-like RNA. Sequence analysis revealed a viroid of 342 nucleotides that contains the central conserved region of coleviroids and is a chimera of the left half of CbVd-3 and the right half of CbVd-5.

Genetic diversity and population structure of rice stripe virus in China.

Rice stripe virus (RSV) is one of the most economically important pathogens of rice and is repeatedly epidemic in China, Japan and Korea. The most recent outbreak of RSV in eastern China in 2000 caused significant losses and raised serious concerns. In this paper, we provide a genotyping profile of RSV field isolates and describe the population structure of RSV in China, based on the nucleotide sequences of isolates collected from different geographical regions during 1997-2004.

Identification and characterization of a new coleviroid (CbVd-5).

A viroid-like RNA was detected from coleus (Coleus blumei) in China. It consisted of 274 nucleotides and had 66% sequence identity with a member of the closest known viroid species. The predicted secondary structure is rod-shaped with extensive base pairing, and it has the conserved region characteristic of the genus Coleviroid.

New asperxanthone and asperbiphenyl from the marine fungus Aspergillus sp.

Background: Marine fungi are of great importance as potential sources of agricultural pesticide leads. To continue work on new and biologically active metabolites from marine fungi, culture extracts of selected isolates were screened for inhibitory activity against tobacco mosaic virus (TMV), a typical member of the tobamovirus group of plant viruses.

Results: A new difuranxanthone, asperxanthone (1), and a new biphenyl, asperbiphenyl (2), as well as seven known unsaturated fatty acid glycerol esters, were isolated from a selected marine fungus, identified as Aspergillus sp.

Two new phenolic water-soluble constituents from branch bark of Davidia involucrata.

Two new phenolic water-soluble constituents, involcranoside A (1) and involcranoside B (2) have been isolated along with five known phenolic compounds: 3,4-dimethoxyphenyl-O-beta-D-gluco-pyranoside (3), picein (4), and 1,4-dihydroxy-3-methoxy-phenyl-4-O-beta-D-glucopyranoside (5), leonuriside A (6) and 4-hydroxy-3-methoxybenzoic acid (7) from the branch bark of Davidia involucrata. Identification of their structures was achieved by 1D and 2D NMR experiments, including (1)H-(1)H COSY, NOESY, HMQC and HMBC methods and FAB mass spectral data.

Molecular variability of Hop stunt viroid: identification of a unique variant with a tandem 15-nucleotide repeat from naturally infected plum tree.

For this study, 68 plum samples were collected from 12 provinces of China. Low molecular weight RNAs were extracted and used for dot-blot, reverse transcription-polymerase chain reaction (RT-PCR), return-polyacrylamide gel electrophoresis, and biological indexing using cucumber. Results showed that 15 out of the 68 plum samples were positive for Hop stunt viroid (HSVd).

Structure-activity relationship of triterpenes and triterpenoid glycosides against tobacco mosaic virus.

A new activity of triterpenes and triterpenoid glycosides against phytovirus has been found. Based on the anti-TMV replication activity in vivo, 47 triterpenes and triterpenoid glycosides were screened through the leaf-disk method together with indirect ELISA. Structure-activity relationships were analyzed according to the results of bio-activity screening.

Antiphytoviral activity of bruceine-D from Brucea javanica seeds.

Background: Brucea javanica (L.) Merr. is widely distributed throughout the southern parts of China and has been used in traditional medicine to treat a variety of diseases.

Six new triterpenoid saponins from the leaves of Ilex oblonga and their inhibitory activities against TMV replication.

Six new triterpenoid saponins of the ursane types were isolated from the MeOH extract of the leaves of Ilex oblonga. They were oblonganoside A (1), oblonganoside B (2), oblonganoside C (6), oblonganoside D (8), oblonganoside E (9), and oblonganoside F (10), together with three known triterpenoid saponins. The structures of these compounds were elucidated on the basis of spectroscopic analysis, and compound 1 showed appreciable inhibitory activity against TMV replication with EC50 value 0.