friedreichs ataxia (frda) is an inherited recessive disorder characterized by progressive neurological disability and heart abnormalities. a deficiency in the protein frataxin causes this disease. frataxin deficiency leads to progressive iron accumulation in mitochondria, excessive free radical production and dysfunction of respiratory chain complexes. the expansion (gaa) repeat in the first in...

objective(s): investigation of acute effect on cellular bioenergetics provides the opportunity to characterize the possible adverse effects of drugs more comprehensively. this study aimed to investigate the changes in biochemical and biophysical properties of heart mitochondria induced by captopril and nifedipine antihypertensive treatment. materials and methods: male, 12-week-old wistar rats i...

The typical archaeal MCM exhibits helicase activity independently in vitro. This study characterizes MCM from the euryarchaeon Picrophilus torridus. While PtMCM hydrolyzes ATP in DNA-independent manner, it displays very poor ability to unwind DNA independently, and then too only under acidic conditions. The protein exists stably in complex with PtGINS in whole cell lysates, interacting directly...

Linear, potato spindle tuber viroid RNA has been used as a substrate for an RNA ligase purified from wheat germ. Linear viroid molecules are efficiently converted to circular molecules (circles) which are indistinguishable by electrophoretic mobility and two-dimensional oligonucleotide pattern from viroid circles extracted from infected plants. In light of recent evidence for multimeric viroid ...

The Mcm2-7 (minichromosome maintenance) complex is a toroidal AAA(+) ATPase and the putative eukaryotic replicative helicase. Unlike a typical homohexameric helicase, Mcm2-7 contains six distinct, essential, and evolutionarily conserved subunits. Precedence to other AAA(+) proteins suggests that Mcm ATPase active sites are formed combinatorially, with Walker A and B motifs contributed by one su...

ATP hydrolysis is required for degradation of polyubiquitinated proteins by the 26S proteasome but is thought to play no role in proteasomal stability during the catalytic cycle. In contrast to this view, we report that ATP hydrolysis triggers rapid dissociation of the 19S regulatory particles from immunopurified 26S complexes in a manner coincident with release of the bulk of proteasome-intera...

Este artigo assume como tema a seleção de materiais para o projeto mobiliários em acampamentos temporários planejados (ATP) cenários desastre. Objetiva analisar, com base um modelo (ESA-MOD), adequação do uso dos nessas estruturas sob ótica constituintes desses equipamentos. Para tanto, realizou uma revisão bibliográfica e busca sistemática literatura englobando arquitetura emergencial incorpor...

When recA protein binds cooperatively to single-stranded DNA to form filamentous nucleoprotein complexes, it becomes competent to hydrolyze ATP. No correlation exists between the ends of such complexes and the rate of ATP hydrolysis. ATP hydrolysis is not, therefore, restricted to the terminal subunits on cooperatively bound recA oligomers, but occurs throughout the complex. Similarly, during r...