scholarly journals Molecular characterization of begomoviruses and DNA satellites from Vietnam: additional evidence that the New World geminiviruses were present in the Old World prior to continental separation

2008 ◽  
Vol 89 (1) ◽  
pp. 312-326 ◽  
Author(s):  
Cuong Ha ◽  
Steven Coombs ◽  
Peter Revill ◽  
Rob Harding ◽  
Man Vu ◽  
...  
Keyword(s):  
New World ◽  
Bipartite Begomoviruses ◽  
Bipartite Begomovirus ◽  
Stem Loop ◽  
Old World ◽  
Recombinant Viruses ◽  
Virus Diversity ◽  
High Degree ◽  
First Time

Sixteen viruses, belonging to 16 species of begomovirus, that infect crops and weeds in Vietnam were identified. Sequence analysis of the complete genomes showed that nine of the viruses (six monopartite and three bipartite) belong to novel species and five of them were identified in Vietnam for the first time. Additionally, eight DNA-β and three nanovirus-like DNA-1 molecules were also found associated with some of the monopartite viruses. Five of the DNA-β molecules were novel. Importantly, a second bipartite begomovirus, Corchorus golden mosaic virus, shared several features with the previously characterized virus Corchorus yellow vein virus and with other bipartite begomoviruses from the New World, supporting the hypothesis that New World-like viruses were present in the Old World. This, together with a high degree of virus diversity that included putative recombinant viruses, satellite molecules and viruses with previously undescribed variability in the putative stem–loop sequences, suggested that South-East Asia, and Vietnam in particular, is one of the origins of begomovirus diversity.

Characterization of SrBi2Nb2O9 Thin Films Prepared by Sol Gel Technique

1996 ◽  
Vol 459 ◽  
Author(s):  
E. Ching-Prado ◽  
W. Pérez ◽  
A. Reynés-Figueroa ◽  
R. S. Katiyar ◽  
D. Ravichandran ◽  
...  
Keyword(s):  
Thin Films ◽  
Raman Band ◽  
Sol Gel ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Ft Ir ◽  
Gel Technique ◽  
High Degree ◽  
First Time

ABSTRACTThin films of SrBi2Nb2O9 (SBN) with thicknesses of 0.1, 0.2, and 0.4 μ were grown by Sol-gel technique on silicon, and annealed at 650°C. The SBN films were investigated by Raman scatering for the first time. Raman spectra in some of the samples present bands around 60, 167, 196, 222, 302, 451, 560, 771, 837, and 863 cm−1, which correspond to the SBN formation. The study indicates that the films are inhomogeneous, and only in samples with thicknesses 0.4 μ the SBN material was found in some places. The prominent Raman band around 870 cm−1, which is the A1g mode of the orthorhombic symmetry, is assigned to the symmetric stretching of the NbO6 octahedrals. The frequency of this band is found to shift in different places in the same sample, as well as from sample to sample. The frequency shifts and the width of the Raman bands are discussed in term of ions in non-equilibrium positions. FT-IR spectra reveal a sharp peak at 1260 cm−1, and two broad bands around 995 and 772 cm−1. The bandwidths of the latter two bands are believed to be associated with the presence of a high degree of defects in the films. The experimental results of the SBN films are compared with those obtained in SBT (T=Ta) films. X-ray diffraction and SEM techniques are also used for the structural characterization.

scholarly journals Amnestus raunoi n. sp. from Iran, the first Old World representative of the New World subfamily Amnestinae (Hemiptera: Heteroptera: Cydnidae)

1998 ◽  
Vol 9 (1) ◽  
pp. 5-7 ◽  
Author(s):  
Jerzy Lis
Keyword(s):  
New Species ◽  
New World ◽  
Old World ◽  
First Time ◽  
A New Species

Amnestus raunoi, a new species from Iran, the representative of the New World subfamily Amnestinae for the first time recorded in the Old World is described, illustrated and compared with its closest relative - A. pusillus Uhler.

scholarly journals Maintenance of an Old World Betasatellite by a New World Helper Begomovirus and Possible Rapid Adaptation of the Betasatellite

2009 ◽  
Vol 83 (18) ◽  
pp. 9347-9355 ◽  
Author(s):  
Muhammad Shah Nawaz-ul-Rehman ◽  
Shahid Mansoor ◽  
Rob W. Briddon ◽  
Claude M. Fauquet
Keyword(s):  
New World ◽  
Cotton Leaf ◽  
Old World ◽  
Tropical Regions ◽  
Cabbage Leaf Curl Virus ◽  
Chili Leaf Curl Betasatellite ◽  
Serious Disease ◽  
Leaf Curl Virus ◽  
First Time ◽  
Leaf Curl

ABSTRACT Begomoviruses (family Geminiviridae) cause major losses to crops throughout the tropical regions of the world. Begomoviruses originating from the New World (NW) and the Old World (OW) are genetically distinct. Whereas the majority of OW begomoviruses have monopartite genomes and whereas most of these associate with a class of symptom-modulating satellites (known as betasatellites), the genomes of NW begomoviruses are exclusively bipartite and do not associate with satellites. Here, we show for the first time that a betasatellite (cotton leaf curl Multan betasatellite [CLCuMuB]) associated with a serious disease of cotton across southern Asia is capable of interacting with a NW begomovirus. In the presence of CLCuMuB, the symptoms of the NW cabbage leaf curl virus (CbLCuV) are enhanced in Nicotiana benthamiana. However, CbLCuV was unable to interact with a second betasatellite, chili leaf curl betasatellite. Although CbLCuV can transreplicate CLCuMuB, satellite accumulation levels in plants were low. However, progeny CLCuMuB isolated after just one round of infection with CbLCuV contained numerous mutations. Reinoculation of one such progeny CLCuMuB with CbLCuV to N. benthamiana yielded infections with significantly higher satellite DNA levels. This suggests that betasatellites can rapidly adapt for efficient transreplication by a new helper begomovirus, including begomoviruses originating from the NW. Although the precise mechanism of transreplication of betasatellites by begomoviruses remains unknown, an analysis of betasatellite mutants suggests that the sequence(s) required for maintenance of CLCuMuB by one of its cognate begomoviruses (cotton leaf curl Rajasthan virus) differs from the sequences required for maintenance by CbLCuV. The significance of these findings and, particularly, the threat that betasatellites pose to agriculture in the NW, are discussed.

scholarly journals A Bipartite Begomovirus Infecting Boerhavia erecta (Family Nyctaginaceae) in the Dominican Republic Represents a Distinct Phylogenetic Lineage and has a High Degree of Host Specificity

2019 ◽  
Vol 109 (8) ◽  
pp. 1464-1474
Author(s):  
Tomas A. Melgarejo ◽  
Maria R. Rojas ◽  
Robert L. Gilbertson
Keyword(s):  
Dominican Republic ◽  
Mosaic Virus ◽  
Phylogenetic Analyses ◽  
Bipartite Begomoviruses ◽  
Mechanical Transmission ◽  
Bipartite Begomovirus ◽  
Degenerate Primers ◽  
Phylogenetic Lineage ◽  
A Genome ◽  
High Degree

Boerhavia erecta plants in and around agricultural fields in the Azua Valley of the southeastern Dominican Republic often show striking golden mosaic symptoms. Leaf samples from B. erecta plants showing these symptoms were collected in 2012 and 2013, and PCR tests with degenerate primers revealed begomovirus DNA-A and DNA-B components. The complete sequences of the DNA-A and DNA-B components of four isolates show a high degree of sequence identity (>96%) and a genome organization typical of New World (NW) bipartite begomoviruses. Sequence comparisons and phylogenetic analyses revealed that these isolates composed a new phylogenetic lineage of NW bipartite begomoviruses. The most closely related begomovirus is Merremia mosaic virus, a weed-infecting species from Puerto Rico. Because DNA-A sequence identities are well below the 91% threshold, these isolates represent a new begomovirus species, for which the name Boerhavia golden mosaic virus (BoGMV) is proposed. Infectious cloned BoGMV DNA-A and DNA-B components induced golden mosaic symptoms in agroinoculated B. erecta plants, thereby fulfilling Koch’s postulates for this disease. Agroinoculation and mechanical transmission experiments revealed that BoGMV has an unusually narrow host range, limited to members of the family Nyctaginaceae and not including the permissive host Nicotiana benthamiana. The inability of BoGMV to infect N. benthamiana was due to a deficiency in cell-to-cell movement but not to a unique amino acid residue in the movement protein.

scholarly journals Corchorus yellow vein virus, a New World geminivirus from the Old World

2006 ◽  
Vol 87 (4) ◽  
pp. 997-1003 ◽  
Author(s):  
Cuong Ha ◽  
Steven Coombs ◽  
Peter Revill ◽  
Rob Harding ◽  
Man Vu ◽  
...  
Keyword(s):  
New World ◽  
Pcr Primers ◽  
Amino Acid Sequences ◽  
Yellow Vein ◽  
Bipartite Begomovirus ◽  
Degenerate Pcr ◽  
Old World ◽  
Reading Frame ◽  
Corchorus Capsularis ◽  
World Begomoviruses

A bipartite begomovirus infecting Jute mallow (Corchorus capsularis, Tilliaceae) in Vietnam was identified using novel degenerate PCR primers. Analysis of this virus, which was named Corchorus yellow vein virus (CoYVV), showed that it was more similar to New World begomoviruses than to viruses from the Old World. This was based on the absence of an AV2 open reading frame, the presence of an N-terminal PWRLMAGT motif in the coat protein and phylogenetic analysis of the DNA A and DNA B nucleotide and deduced amino acid sequences. Evidence is provided that CoYVV is probably indigenous to the region and may be the remnant of a previous population of New World begomoviruses in the Old World.

The planthopper genus Stenocranus in Canada: implications for classification of Delphacidae (Hemiptera)

2006 ◽  
Vol 138 (4) ◽  
pp. 493-503 ◽  
Author(s):  
K G.A. Hamilton
Keyword(s):  
New World ◽  
Hierarchical Classification ◽  
Species Concepts ◽  
Evolutionary Relationships ◽  
World Species ◽  
Old World ◽  
The World ◽  
First Time

AbstractThe Canadian species of Stenocranus Fieber are keyed by external characters correlated with species concepts defined by known genitalic characters. Stenocranus is differentiated from Terauchiana Matsumura (Asian; here reported from the New World for the first time) and Embolophora Stål (from Africa) by the remarkable development of the female pygofers, which completely conceal the ovipositor. Based on both head and genitalic characters, the genus is divided into two subgenera: typical Stenocranus with many Old World species and two Canadian species, and subgenus Codexnov. for other New World species. The type of Delphax dorsalis Fitch, 1851 is a specimen of Stenocranus pallidus Beamer, 1946 syn. nov., and "S. dorsalis" sensu Beamer is S. unipunctatus (Provancher, 1872). A lectotype of Delphax vittata Stål, 1862 is designated for the taxon S. unipunctatus (sensu Beamer, nec Provancher); its paralectotypes are specimens of S. acutus Beamer. The apparent evolutionary relationships of this fauna to other species of the world Stenocranini and within the superficially similar Saccharosydnini reveal numerous homoplasies and dramatic autapomorphies, contrasted with only a few reliable synapomorphies. A hierarchical classification of Delphacidae, based on the most distinctive synapomorphies, defines subfamily Delphacinae as encompassing at least four tribes: Vizcayini, Stenocranini, Tropidocephalini, and Delphacini, with "Kelisiinae" reduced to subtribe of Stenocranini and "Saccharosydnini" placed within Tropidocephalini.

scholarly journals Genus Coltivirus (family Reoviridae): genomic and morphologic characterization of Old World and New World viruses

2002 ◽  
Vol 147 (3) ◽  
pp. 533-561 ◽  
Author(s):  
H. Attoui ◽  
F. Mohd Jaafar ◽  
P. Biagini ◽  
J.-F. Cantaloube ◽  
P. de Micco ◽  
...  
Keyword(s):  
New World ◽  
Old World

scholarly journals Mycobacterium tuberculosis and Paracoccidioides brasiliensis Formation and Treatment of Mixed Biofilm In Vitro

2021 ◽  
Vol 11 ◽  
Author(s):  
Kaila Petronila Medina-Alarcón ◽  
Iara Pengo Tobias da Silva ◽  
Giovana Garcia Ferin ◽  
Marcelo A. Pereira-da-Silva ◽  
Caroline Maria Marcos ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Paracoccidioides Brasiliensis ◽  
Public Health Problem ◽  
Extracellular Polysaccharide ◽  
Force Microscopy ◽  
Atomic Force ◽  
High Degree ◽  
First Time

Co-infection of Mycobacterium tuberculosis and Paracoccidioides brasiliensis, present in 20% in Latin America, is a public health problem due to a lack of adequate diagnosis. These microorganisms are capable of forming biofilms, mainly in immunocompromised patients, which can lead to death due to the lack of effective treatment for both diseases. The present research aims to show for the first time the formation of mixed biofilms of M. tuberculosis and P. brasiliensis (Pb18) in vitro, as well as to evaluate the action of 3’hydroxychalcone (3’chalc) -loaded nanoemulsion (NE) (NE3’chalc) against monospecies and mixed biofilms, the formation of mixed biofilms of M. tuberculosis H37Rv (ATCC 27294), 40Rv (clinical strains) and P. brasiliensis (Pb18) (ATCC 32069), and the first condition of formation (H37Rv +Pb18) and (40Rv + Pb18) and second condition of formation (Pb18 + H37Rv) with 45 days of total formation time under both conditions. The results of mixed biofilms (H37Rv + Pb18) and (40Rv + Pb18), showed an organized network of M. tuberculosis bacilli in which P. brasiliensis yeasts are connected with a highly extracellular polysaccharide matrix. The (Pb18 + H37Rv) showed a dense biofilm with an apparent predominance of P. brasiliensis and fragments of M. tuberculosis. PCR assays confirmed the presence of the microorganisms involved in this formation. The characterization of NE and NE3’chalc displayed sizes from 145.00 ± 1.05 and 151.25 ± 0.60, a polydispersity index (PDI) from 0.20± 0.01 to 0.16± 0.01, and zeta potential -58.20 ± 0.92 mV and -56.10 ± 0.71 mV, respectively. The atomic force microscopy (AFM) results showed lamellar structures characteristic of NE. The minimum inhibitory concentration (MIC) values of 3’hidroxychalcone (3’chalc) range from 0.97- 7.8 µg/mL and NE3’chalc from 0.24 - 3.9 µg/mL improved the antibacterial activity when compared with 3’chalc-free, no cytotoxicity. Antibiofilm assays proved the efficacy of 3’chalc-free incorporation in NE. These findings contribute to a greater understanding of the formation of M. tuberculosis and P. brasiliensis in the mixed biofilm. In addition, the findings present a new possible NE3’chalc treatment alternative for the mixed biofilms of these microorganisms, with a high degree of relevance due to the lack of other treatments for these comorbidities.

scholarly journals Ampelographic and Genetic Characterization of Grapevine Varieties (Vitis vinifera L.) of the ‘Mavroudia’ Group Cultivated in Greece

2017 ◽  
Vol 45 (2) ◽  
pp. 525-531 ◽  
Author(s):  
Maritina STAVRAKAKI ◽  
Katerina BINIARI
Keyword(s):  
Genetic Similarity ◽  
Genetic Characterization ◽  
Vitis Vinifera L ◽  
Molecular Method ◽  
Grapevine Cultivar ◽  
Parent Variety ◽  
High Degree ◽  
First Time ◽  
Very High

Twenty-one grapevine varieties grown all over Greece and belonging to ‘Mavroudia’ group were ampelographically described and genotyped by AFLP molecular analysis in order to discriminate the varieties, synonyms, homonyms and variations of the group. In most cases, the molecular findings confirmed the results of the ampelographic description. In general, and despite the high degree of genetic similarity between certain pairs of the studied cultivars, the group of ‘Mavroudia’ was characterized as being heterogeneous. From the studied cultivars, ‘Kountoura mavri’, ‘Mavro Spetson’ and ‘Pappoudes’ showed very high degree of genetic similarity, sustaining the hypothesis that the last two are clones of the first. Grapevine cultivar ‘Pappoudes’ was for the first time ampelographically described and identified as being closely related to ‘Kountoura mavri’. High degree of genetic similarity was observed between cultivars ‘Gaidouricha’ and ‘Agiomavritiko’, suggesting that they probably originated from the same parent variety through the accumulation of mutations. This may also be true for cultivars ‘Mavrokorakas’ and ‘Kartsiotis’. Also, the results from the statistical analysis showed that ‘Mavro Arachovis’, ‘Mavroudi Voulgarias’ and ‘Voulgaroudes’, despite the relatively high genetic similarity between them, are different. The same applies for the rest of the cultivars studied, while ‘Mavro Kalavriton’, the most widespread variety of the ‘Mavroudia’ group, showed the lowest degree of genetic similarity within the all the cultivars studied. The ampelographic description in combination with the molecular method AFLP are effective for the study of the between and within genetic diversity of grapevine cultivars as well as for their identification and discrimination.

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