The ability to induce an extracellular DNase from a novel thermophilic fungus was studied and the DNAse purified using both traditional and innovative purification techniques. The isolate produced sterile hyphae under all attempted growing conditions, with an average diameter of 2 µm and was found to have an optimal temperature of 45 °C and a maximum of 65 °C. Sequencing of the internal transcr...

The species Campylobacter jejuni is considered naturally competent for DNA uptake and displays strong genetic diversity. Nevertheless, nonnaturally transformable strains and several relatively stable clonal lineages exist. In the present study, the molecular mechanism responsible for the nonnatural transformability of a subset of C. jejuni strains was investigated. Comparative genome hybridizat...

Ischemia/reperfusion is known to result in DNA fragmentation and cell death in kidney tubular epithelium, but the endonucleases responsible for this DNA damage have not been identified. DNA substrate gel analysis of extracts from normal rat kidney cortex revealed the presence of a DNase with an apparent molecular mass of 30 to 34 kD. This enzyme is not a dimer of the previously described nuclea...

Of the four deoxyribonucleases, DNases A, B, C, and D, observable by chromatography of preparations of the pancreatic enzyme on cellulose phosphate, DNase D, the component present in the smallest amount, has not been previously characterized. Peptide maps show that the sequence of the amino acid residues in the polypeptide chain of DNase D is indistinguishable from that of DNase C; analysis of ...

Light-induced retinal degeneration is characterized by photoreceptor cell death. Many studies showed that photoreceptor demise is caspase-independent. In our laboratory we showed that leucocyte elastase inhibitor/LEI-derived DNase II (LEI/L-DNase II), a caspase-independent apoptotic pathway, is responsible for photoreceptor death. In this work, we investigated the activation of a pro-survival k...

Streptococci of serological groups A and C are known to produce substantial amounts of extracellular deoxyribonuclease (l-4). Evidence that the nuclease activity is probably due to the presence of more than one enzyme was suggested by the finding of Bernheimer (5) that ribonucleic acid from a variety of sources could inhibit to varying degrees the DNase activity of group A streptococci but did ...

Effect of repeated (20 days) exposure to picrotoxin (PTX) on rat liver lysosomal function was evaluated by measuring the free and total activities of acid phosphatase, cathepsin D, ribonuclease II (RNAse II) and deoxyribonuclease II (DNAse II). The free activities of the nucleases (both RNAse II and DNAse II) were increased following PTX exposure. The total DNAse II activity was increased by 2....

Extracts of purified mitochondria from adult rabbit liver and kidney have been prepared by lysis with Triton X-100. Such extracts contain deoxyribonuclease activity demonstrable at alkaline pH. Studies utilizing the effects of substrate variation, differing ionic strength, nucleoside di- and triphosphates, and SH-group inhibitors reveal the existence of at least five distinguishable deoxyribonu...

The activation of endonucleases resulting in the degradation of genomic DNA is one of the most characteristic changes in apoptosis. Here, we report the characterization of a novel endonuclease, termed DNase X due to its X-chromosomal localization. The active nuclease is a 35 kDa protein with 39% identity to DNase I. When incubated with isolated nuclei, recombinant DNase X was capable of trigger...