BACKGROUND Human skin is able to mount a fast response against invading microorganisms by the release of antimicrobial proteins such as the ribonuclease RNase 7. Because RNase 7 exhibits high activity against Enterococcus faecium the aim of this study was to further explore the role of RNase 7 in the cutaneous innate defense system against E. faecium. METHODOLOGY/PRINCIPAL FINDINGS Absolute q...

Ribonuclease P (RNase P) is an essential endonuclease responsible for the 5'-end maturation of precursor tRNAs. Bacterial RNase P also processes precursor 4.5S RNA, tmRNA, 30S preribosomal RNA, and several reported protein-coding RNAs. Eukaryotic nuclear RNase P is far more complex than in the bacterial form, employing multiple essential protein subunits in addition to the catalytic RNA subunit...

The planctomycetes, order Planctomycetales, are a distinct phylum of domain Bacteria. Genes encoding the RNA portion of ribonuclease P (RNase P) of some planctomycete members were sequenced and compared with existing database planctomycete sequences. rnpB gene sequences encoding RNase P RNA were generated by a conserved primer PCR strategy for Planctomyces brasiliensis, Planctomyces limnophilus...

RNase P is an essential enzyme that cleaves the 5' leader sequence of tRNA precursors. RNase Ps were believed until now to occur universally as ribonucleoproteins in organisms performing RNase P activity. Here we find that protein-only RNase P enzymes called PRORP (for proteinaceous RNase P) support RNase P activity in vivo in both organelles and the nucleus in Arabidopsis. Beyond tRNA, PRORP p...

Salt concentration and pH have dramatic effects on enzymatic catalysis. A quantitative description on these effects is important to elucidate the energetics and mechanisms of catalysis. Here, the effects of salt concentration and pH on binding and catalysis are analyzed with Ribonuclease A (RNase A) as a model system. 11 The effects of pH and mutagenesis on the stability of RNase A-nucleic acid...

Theiler's virus is a neurotropic picornavirus responsible for chronic infections of the central nervous system. The establishment of a persistent infection and the subsequent demyelinating disease triggered by the virus depend on the expression of L*, a viral accessory protein encoded by an alternative open reading frame of the virus. We discovered that L* potently inhibits the interferon-induc...

Protein fibrils termed amyloid-like are associated with numerous degenerative diseases as well as some normal cellular functions. Specific short segments of amyloid-forming proteins have been shown to form fibrils themselves. However, it has not been shown in general that these segments are capable of driving a protein from its native structure into the amyloid state. We applied the 3D profile ...

We cloned a cDNA for a gibberellin-induced ribonuclease (RNase) expressed in barley (Hordeum vulgare) aleurone and the gene for a second barley RNase expressed in leaf tissue. The protein encoded by the cDNA is unique among RNases described to date in that it contains a novel 23-amino acid insert between the C2 and C3 conserved sequences. Expression of the recombinant protein in tobacco (Nicoti...

In Escherichia coli, the cold shock response is exerted upon a temperature change from 37 degrees C to 15 degrees C and is characterized by induction of several cold shock proteins, including polynucleotide phosphorylase (PNPase), during acclimation phase. In E. coli, PNPase is essential for growth at low temperatures; however, its exact role in this essential function has not been fully elucid...

The genes encoding the ribonucleases RNase J1 and RNase Y have long been considered essential for Bacillus subtilis cell viability, even before there was concrete knowledge of their function as two of the most important enzymes for RNA turnover in this organism. Here we show that this characterization is incorrect and that ΔrnjA and Δrny mutants are both viable. As expected, both strains grow r...