background and aims: infectious bronchitis virus (ibv) is the etiological agent of infectious bronchitis (ib), which is an acute and highly contagious disease of the respiratory and sometimes the urogenital tracts of chickens. in iran, the disease has been identified in chicken flocks with serological and virus isolation methods. gene 3c (e) encode envelop (small membrane) protein. for envelope...

background: fasciola species are parasitic trematode with world wide distribution that infects wild and domesticated herbivores, particularly ruminants. the aim of the present study was to investigate the intra species variations of f. gigantica, from goats and buffalos isolates in two common geographic climates of iran. methods: fasciola species were collected from goat, buffalo, sheep, and ca...

the pb2 protein of influenza a viruses has been shown as host range determinant. in this study pb2gene of five h9n2 isolates from tehran province during the period of 1998-2001 were partially amplifiedand sequenced to do phylogenetic study. iranian isolates could be classified in eurasian lineage according totheir pb2 gene sequences. the pb2 genes of these isolates are different from those of m...

phylogenetic analysis has shown that escherichia coli is composed of four main phylogenetic groups (a, b1, b2 and d). characterization of phylogenetic groups is of clinical interest, as group a and b1 generally associated with commensals, whereas most enteropathogenic isolates are assigned to group d, and group b2 is associated with extra-intestinal pathotype. one hundred e. coli strains recove...

the earliest evidences on circulation of avian influenza (ai) virus on the iranian poultry farms date back to 1998. great economic losses through dramatic drop in egg production and high mortality rates are characteristically attributed to h9n2 ai virus. in the present work non-structural (ns) genes of 10 iranian h9n2 chicken ai viruses collected during 1998-2007 were fully sequenced and subjec...

Two genes are xenologs in the sense of Fitch if they are separated by at least one horizontal gene transfer event. Horizonal gene transfer is asymmetric in the sense that the transferred copy is distinguished from the one that remains within the ancestral lineage. Hence xenology is more precisely thought of as a nonsymmetric relation: y is xenologous to x if y has been horizontally transferred ...

Pediococci are found in foods and on plants and as beer-spoilage agents. The goal of the present study was to use the DNA sequences of the first three variable regions of the 165 rRNA gene, the 16S-23S rRNA internally transcribed spacer region sequence and approximately a third of the 60 kDa heat-shock protein gene to elucidate phylogenetic groupings within the genus Pediococcus. Phylogenetic t...

Advances in the taxonomy and ecological aspects concerning geographical distribution and hosts of the so far genetically recognised nine taxa of the nematodes belonging to genus Anisakis (i.e. A. pegreffii, A. simplex s.s., A. simplex C, A. typica, A. ziphidarum, Anisakis sp., A. physeteris, A. brevispiculata and A. paggiae) are here summarized. Genetic differentiation and phylogenetic relation...

A phylogenetic 'tree of life' has been constructed based on the observed presence and absence of families of protein-encoding genes observed in 11 complete genomes of free-living microorganisms. Past attempts to reconstruct the evolutionary relation-ships of microorganisms have been limited to sets of genes rather than complete genomes. Despite apparent rampant lateral gene transfer among micro...

Teleost fishes comprise more than half of all vertebrate species, yet genomic data are only available for 0.2% of their diversity. Here, we present whole genome sequencing data for 66 new species of teleosts, vastly expanding the availability of genomic data for this important vertebrate group. We report on de novo assemblies based on low-coverage (9-39×) sequencing and present detailed methodo...