background: accurate identification of sheep nematodes is a critical point in epidemiological studies and monitoring of drug resistance in flocks. however, due to a close morphological similarity between the eggs and larval stages of many of these nematodes,such identification is not a trivial task. there are a number of studies showing that molecular targets in ribosomal dna (internal transcri...

We report the presence, in the mitochondrial DNA (mtDNA) of all of the sexual species of the salamander family Ambystomatidae, of a shared 240-bp intergenic spacer between tRNAThr and tRNAPro. We place the intergenic spacer in context by presenting the sequence of 1,746 bp of mtDNA from Ambystoma tigrinum tigrinum, describe the nucleotide composition of the intergenic spacer in all of the speci...

16S/23S intergenic spacer regions from the rRNA operons of two strains of “Candidatus Liberobacter asiaticum” and one strain of “Candidatus Liberobacter africanum” were cloned and sequenced. The intergenic spacers of the two “Candidatus L. asiaticum” strains studied are identical and contain the genes for isoleucine tRNA (tRNA”‘) and alanine tRNA (tRNAMa) separated by 11 nucleotides. The interg...

The 16S-23S rRNA intergenic spacer regions of 14 strains representing the 14 serovars of Ureaplasma urealyticum were amplified by PCR and sequenced for genetic differentiation between the two biovars Parvo and T960. Although the spacer region of the Parvo and T960 biovars comprised 302 nucleotides and lacked spacer tRNA genes, 15 nucleotides were different between the two biovars. The four nucl...

To choose a suitable DNA marker to authenticate the botanical origins of Flos Lonicerae Japonicae and Flos Lonicerae, seven candidate DNA bar codes (i.e., RBCL, MATK, PSBA-TRNH, ITS2, ITS, TRNL intron, and TRNL-F intergenic spacer) were tested on forty-four samples of LONICERA JAPONICA and its closely related species using the DNA barcoding method. We found that all seven candidate bar codes yi...

background and objective : chlamydophila psittaci is a lethal bacterium that causes endemic avian chlamydiosis, and respiratory psittacosis. laboratory diagnosis of chlamydophila psittaci is difficult by culture. this study was design to investigate the presence of chlamydophila psittaci in collected pharyngeal swabs from asyptomatic pigeons by pcr. materials and methods : pharyngeal samples fr...

With the financial protection of National Iranian Copper Industries Company, the composition of bacterial populations in Aliabad copper mine was investigated by electron microscopy and by analysis of DNA obtained from bacteria after ores laboratory cultures. This analysis consisted of the characterization of the spacer regions between the 16 and 23s genes in the bacterial rRNA genetic loci afte...

The human rDNA tandem repeat consists of 13.3 kb of transcribed sequence and about 30 kb of intergenic spacer of unknown function. For descriptive purposes, it is convenient to divide the ribosomal repeat into 4 EcoRI fragments, A D . The C fragment contains only intergenic spacer sequences, and ends some 500 bp upstream of the ribosomal RNA promoter. We had previously described the terminal Ba...

Noncoding DNA sequences from numerous regions of the chloroplast genome have provided a significant source of characters for phylogenetic studies in seed plants. In lycophytes and monilophytes (leptosporangiate ferns, eusporangiate ferns, Psilotaceae, and Equisetaceae), on the other hand, relatively few noncoding chloroplast DNA regions have been explored. We screened 30 lycophyte and monilophy...