RESUMEN
The complete genome sequence of a Brazilian isolate of yambean mosaic virus (YBMV) is presented. High-throughput sequencing (Illumina HiSeq) and Sanger sequencing revealed the complete genome sequence of the YBMV-BRA-6 isolate, found in Canavalia ensiformis. The de novo contigs were assembled into a 9612 nucleotides (nt) long scaffold, excluding the 3'-terminal poly(A) tail, covering the complete genome. The genomic RNA contains an open reading frame (ORF) typical of members of the genus Potyvirus, family Potyviridae, encoding a large putative polyprotein of 3078 amino acids (aa) and a small overlapping PIPO ORF. Pairwise comparisons showed that the YBMV-BRA-6 isolate sequence shares 88.1% nt identity for the complete genome and 90.6% aa identity for the polyprotein with the YBMV-SR isolate. Phylogenetic analysis grouped both isolates together and close to bean common mosaic virus (BCMV). The polyprotein cleavage sites were predicted and a recombination event is described.
Asunto(s)
Canavalia , Potyvirus , Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento , Sistemas de Lectura Abierta , Filogenia , Poliproteínas/genética , Potyvirus/genética , ARN Viral/genéticaRESUMEN
In this study, the complete nucleotide sequence of a Brazilian isolate of cowpea severe mosaic virus (CPSMV) is presented for the first time. To date, the CPSMV-DG isolate, from the USA, is the only one with the complete known genome. High-throughput sequencing (Illumina HiSeq) and Sanger sequencing of the total RNA extract from a cowpea plant collected in Teresina city, Brazil, revealed the genome sequence of the CPSMV-Ter1 isolate. RNA-1 and RNA-2 are, respectively, 5921 and 3465 nucleotides (nt) long without the poly(A) tail, and show 77.91% and 76.08% nt sequence identity with CPSMV-DG, considered the type isolate of the species. The open reading frames (ORFs) were determined and the cleavage sites of the polyproteins were predicted. Although the two isolates show a similar genomic organization, there was a low percentage of sequence identity between Ter1 and DG. Furthermore, pairwise comparisons of a partial RNA-1 fragment between CPSMV-Ter1 and 11 CPSMV isolates from Brazil indicated 94.6 to 94.8% nt and 98.9% to 99.4% aa sequence identities.
Asunto(s)
Comovirus/genética , Genoma Viral , Brasil , Comovirus/aislamiento & purificación , ARN Viral , Análisis de Secuencia de ARN , Vigna/virología , Secuenciación Completa del GenomaRESUMEN
A distinct bipartite begomovirus was isolated in northeastern Brazil infecting Macroptilium lathyroides showing symptoms of yellow mosaic. The complete genome (DNA-A and DNA-B) of the virus was cloned using rolling circle amplification and subsequently sequenced. Clones presented the typical genomic organization of a New World bipartite begomovirus. Based on the current taxonomic criteria established for the genus Begomovirus, the virus corresponds to a new species, showing highest nucleotide identity with other Brazilian begomoviruses that infect leguminous hosts. In phylogenetic analysis the virus clustered with bean golden mosaic virus. Recombination events were not detected. We propose the name Macroptilium common mosaic virus (MacCMV) for the virus reported in this study.
Asunto(s)
Begomovirus/genética , Fabaceae/virología , Genoma Viral , Enfermedades de las Plantas/virología , Brasil , ADN Viral/genética , FilogeniaRESUMEN
A high diversity of begomoviruses that infect non-cultivated plants has been noted in Brazil. Here, we report the complete sequences of two new species of bipartite begomoviruses from Sida sp. plants collected in the state of Piauí, northeastern Brazil. The genomes of these viruses show a genomic organization that is typical of New World begomoviruses. In phylogenetic analysis, two closely related viruses (sida angular mosaic virus, SiAMV and sida chlorotic vein virus, SiCVV) clustered with other begomoviruses described in tomato and Sida plants in Brazil. Evidence of recombination is shown among isolates of the species described.
Asunto(s)
Begomovirus/aislamiento & purificación , Malvaceae/virología , Enfermedades de las Plantas/virología , Secuencia de Bases , Begomovirus/clasificación , Begomovirus/genética , Brasil , Genoma Viral , Solanum lycopersicum/virología , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Análisis de Secuencia de ADNRESUMEN
The complete genomic sequences of two cowpea aphid-borne mosaic virus (CABMV) isolates from Brazil, MG-Avr from passion fruit (which also infects cowpea), and BR1 from peanut (which also infects cowpea, but not passion fruit), were determined. Their nucleotide sequences are 89% identical and display 85% identity to that of CABMV-Z. Both isolates have the typical potyvirus genome features. P3 and VPg are the most conserved proteins, with 99% amino acid sequence identity between the two isolates, and P1 is the most variable, with 50% identity. A significant variation exists at the 5'-end of the genome between the Brazilian isolates and CABMV-Z. However, this variation does not correlate with the biological properties of these three isolates.
Asunto(s)
Arachis/virología , Comovirus/genética , Genoma Viral , Passiflora/virología , Secuencia de Aminoácidos , Secuencia de Bases , Brasil , Comovirus/clasificación , Comovirus/aislamiento & purificación , Datos de Secuencia Molecular , Filogenia , Potyvirus/genética , Potyvirus/aislamiento & purificación , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Proteínas Virales/química , Proteínas Virales/genéticaRESUMEN
The incidence of tomato-infecting begomoviruses has sharply increased in Brazil following the introduction of the B biotype of the whitefly vector in the early 1990s. Five definitive species and six tentative species have been described since then. Here, we report the detection of members of an additional six novel species, three in tomato and three infecting weeds that are commonly associated with tomato fields: Blainvillea rhomboidea, Sida rhombifolia and Sida micrantha. Tomato and weed samples were collected in two major tomato-growing regions of southeastern Brazil in 2005 and 2007. Two of the novel viruses were present in tomato plants collected in Paty do Alferes, Rio de Janeiro state. Three novel viruses were present in weed samples collected in Coimbra, Minas Gerais state. One virus was present in tomato samples collected at both locations. Genome features indicate that all six species are typical New World, bipartite begomoviruses. However, the viruses belonging to two of the novel species did not cluster with the Brazilian viruses in a phylogenetic tree. These species could represent a distinct lineage of New World begomoviruses, found in Brazil for the first time.