Nearly 800 nucleotides from the 5' terminus of the 28S ribosomal gene of Paracoccidioides brasiliensis were sequenced, and a 14-base DNA probe specific for this species was identified. Hybridization results showed that the probe identified P. brasiliensis ribosomal DNA in a panel of ribosomal DNAs representing a total of 48 species of fungi.

The DNA sequences of eight yeast ribosomal protein genes have been compared for the purpose of identifying homologous regions which may be involved in the coordinate regulation of ribosomal protein synthesis. A 12 bp homology was identified in the 5' DNA sequence preceding the structural gene for 6 out of 8 yeast ribosomal protein genes. In each case the homologous sequence was found at a posit...

The impact of three different soil DNA extraction methods on bacterial diversity was evaluated using PCR-based 16S ribosomal DNA analysis. DNA extracted directly from three soils showing contrasting physicochemical properties was subjected to amplified ribosomal DNA restriction analysis and ribosomal intergenic spacer analysis (RISA). The obtained RISA patterns revealed clearly that both the ph...

The DNA gyrase inhibitor novobiocin specifically inhibits the transcription of ribosomal RNA in vivo while protein synthesis and the mRNA transcription are only partly affected. In vitro the novobiocin inhibition is only observed when protein fraction, which stimulates ribosomal RNA synthesis, is present. These results indicate that DNA gyrase is involved in the transcription of ribosomal RNA, ...

Passion fruit (Passiflora edulis) is one of the tropical fruits well-adapted to Florida’s hot and humid climate. A high population root-knot nematode, Meloidogyne incognita was identified morphologically from soil samples taken declined passion vines in an organic field North Florida. Species identification also confirmed based on DNA-based diagnostics using species-specific primers sequencing ...

Synchronised cells of Tetrahymena pyriformis GL were labelled with 3H thymidine at a stage in the cell cycle when only the mitochondrial and extrachromosomal nucleolar ribosomal DNAs were replicating. In this way it was possible to prepare nuclei labelled selectively in the DNA of the ribosomal RNA genes. Since the ribosomal RNA cistrons of these cells are also very active in serving as a templ...

During the study on endophytic fungi of grapevine (Vitis vinifera L.), 655 fungal isolates were obtained and studied taxonomically. Based on morphological and ITS sequences data, 15 species belonging to 10 genera including Alternaria brassicicola, A. chlamydospora, A. malorum, A. atra, Arthrinium phaeospermum, A. sacchari, Aspergillus nidulans, A. wentii, Beauveria bassiana, Cheatomium elatum, ...

An acidic nucleolar phosphoprotein with a subunit M(r) of 70,000 was purified as an apparent dimer of 139,000 from isolated nuclei of the slime mold Physarum polycephalum. The protein was purified without the aid of strong dissociating agents after its selective phosphorylation in isolated nuclei by a polyamine-mediated reaction. Its amino acid composition resembled that of a nucleolar phosphop...

Micrococcal nuclease digestion was used as a tool to study the organization of the ribosomal chromatin in liver, blood and embryo cells of X. laevis. It was found that in liver and blood cells, ribosomal DNA is efficiently protected from nuclease attack in comparison to bulk chromatin. Although ribosomal chromatin is fragmented in a typical nucleosomal pattern, a considerable portion of ribosom...

The major chromomere of pachytene chromosome 6 in the oocytes of Acheta (Orthoptera) is a region of amplification for ribosomal RNA cistrons (28 S and 18 S). This chromomere was isolated and studied with the scanning electron microscope. It has an outer shell that is smooth at early stages but divides into polygonal plates as indentations appear on its surface. These indentations increase in nu...