Search results for "Phylogenetic analysi"
showing 6 items of 56 documents
Fasciolasis humana y animal en África, con enfásis en Egipto
2013
Fasciolid flukes cause fascioliasis, an helminthic disease of humans and livestock and which is transmitted by specific freshwater snails of the family Lymnaeidae, within a frame of transmission and epidemiology pronouncedly influenced by climate factors and environmental conditions. In Africa, fascioliasis is caused by the two species Fasciola hepatica and F. gigantica, giving rise to important economic losses in husbandry throughout. Research on human infection has focused on northern Maghreb countries and Egypt, whereas studies on the wide region southward from the Sahara have only been sporadic. The present Thesis includes the genetic characterisation of the lymnaeid species found in se…
Genotyping of bovine diarrhea virus (BVDV) isolated from cattle in Sicily
2011
Bovine Viral Diarrhoea - Mucosal Disease (BVD-MD) is a widely spread infectious disease that cause economically important losses in farms. Several epidemiological studies indicate a high genetic heterogeneity among Bovine Viral Diarrhoea Virus (BVDV) strains circulating in Italy. The aim of this study was to investigate the genotypes of BVDV in Sicily, a region in the South of Italy. For this purpose, 17 BVDV strains collected from cattle breed in Sicily between 2005 and 2008 were genetically typed by sequencing of 5'-untraslated region (5’-UTR) of the viral genome. In this study, phylogenetic analysis showed that all 17 examined strains were clustered within the BVDV genotype 1. Particular…
Evolutionary Analysis of Grapevine Virus A: Insights into the Dispersion in Sicily (Italy)
2022
Grapevine virus A (GVA) is a phloem-restricted virus (genus Vitivirus, family Betaflexiviridae) that cause crop losses of 5–22% in grapevine cultivars, transmitted by different species of pseudococcid mealybugs, the mealybug Heliococcus bohemicus, and by the scale insect Neopulvinaria innumerabilis. In this work, we studied the genetic structure and molecular variability of GVA, ascertaining its presence and spread in different commercial vineyards of four Sicilian provinces (Italy). In total, 11 autochthonous grapevine cultivars in 20 commercial Sicilian vineyards were investigated, for a total of 617 grapevine samples. Preliminary screening by serological (DAS-ELISA) analysis for GV…
Genetic diversity and evolutionary analysis of Citrus Tristeza Virus p20 gene in Pakistan: insights into the spread and epidemiology
2016
Background: Citrus tristeza virus (CTV) is a widespread disease and the most destruction causing agent of citrus. Pakistan is ranked amongst the top ten citrus producing countries around the globe and it contributes about 2% to its foreign exchange earnings. Based on this assumption it is very important to monitor and determine the evolutionary forces and the phylogeography of Pakistani CTV population. Methods: A total of 49 sequences of p20 gene from Pakistan were phylogenetically compared with CTV sequences worldwide. These sequences were analyzed for their genetic diversity and evolution using a Bayesian Probability approach and predicted secondary structure. Results: Phylogenetic analys…
Molecular evolution of aphids and their primary (Buchnera sp.) and secondary endosymbionts: Implications for the role of symbiosis in insect evolution
2001
Aphids maintain an obligate, endosymbiotic association with Buchnera sp., a bacterium closely related to Escherichia coli. Bacteria are housed in specialized cells of organ-like structures called bacteriomes in the hemocoel of the aphid and are maternally transmitted. Phylogenetic studies have shown that the association had a single origin, dated about 200-250 million years ago, and that host and endosymbiont lineages have evolved in parallel since then. However, the pattern of deepest branching within the aphid family remains unsolved, which thereby hampers an appraisal of, for example, the role played by horizontal gene transfer in the early evolution of Buchnera. The main role of Buchner…
The genome sequence of Blochmannia floridanus: Comparative analysis of reduced genomes
2003
Bacterial symbioses are widespread among insects, probably being one of the key factors of their evolutionary success. We present the complete genome sequence of Blochmannia floridanus , the primary endosymbiont of carpenter ants. Although these ants feed on a complex diet, this symbiosis very likely has a nutritional basis: Blochmannia is able to supply nitrogen and sulfur compounds to the host while it takes advantage of the host metabolic machinery. Remarkably, these bacteria lack all known genes involved in replication initiation ( dna A, pri A, and rec A). The phylogenetic analysis of a set of conserved protein-coding genes shows that Bl. floridanus is phylogenetically related to Buch…