pyruvate kinase is a key enzyme in glycolytic pathway that catalyzes the transphosphorylation between phosphoenolpyruvate and adp to yield atp and pyruvate. geobacillus stearothermophillus has a stable pyruvate kinase with determined crystal structure that composed of four separate domains. given that limited proteolysis experiments can be successfully used to probe conformational features of p...

INTRODUCTION The intracellular level of a protein is dependent on both its rate of synthesis and its rate of degradation. Thus, differential regulation of protein stability represents a potential mechanism for modulating gene expression. lncreasing evidence suggests that protein degradation is indeed a regulatory mechanism in vivo. Dramatic differences in the in vivo stability of different prot...

Ubiquitination (a.k.a. ubiquitylation) is a protein post-translational modification that typically requires the sequential action of three enzymes: E1 (ubiquitin-activating enzymes), E2 (ubiquitin-conjugating and E3 (ubiquitin ligases) [28]. proteins can target them for proteasomal degradation, or modulate cellular processes including cell cycle progression, transcriptional regulation, DNA repa...

Bacterial proteases participate in the proteolytic elimination of misfolded or aggregated proteins, carried out by members AAA+ protein superfamily such as Hsp100/Clp, Lon, and FtsH. It is estimated that Clp Lon families perform around 80% cellular proteolysis bacteria. These functions are regulated, part, through spatial and/or temporal use adapter which recognition delivery specific substrate...

Rat plasma fibronectin has been isolated and characterized and monospecific antibodies were prepared to it. Two components of fresh rat plasma (in the presence of proteinase inhibitors) bound to a gelatin-Sepharose affinity column. One protein was eluted with 4.0 M-urea and was identified as fibronectin. Another protein was eluted from the gelatin-Sepharose column with 8.0 M-urea and was identi...

Targeted protein proteolysis is increasingly understood to be an important general mechanism by which cells regulate protein levels — and consequently their functions at specific times. In eukaryotic cells, the main mechanism for such control involves the specific covalent modification by polyubiquitin, which labels target proteins for proteolysis and subsequent degradation. There are many know...

In recent years it has become apparent that the hemostatic system has a role to play in regulating angiogenesis. This is achieved by components of the coagulation and fibrinolytic systems regulating proteolysis in the milieu and context of extra cellular matrix and the fibrin clot. It is also an emerging paradigm that cryptic fragments, released by proteolysis from components of the coagulation...

Proteasomes are large protein complexes, whose main function is to degrade unnecessary or damaged proteins. The inhibition of proteasome activity in Trypanosoma cruzi blocks parasite replication and cellular differentiation. We demonstrate that proteasome-dependent proteolysis occurs during the cellular differentiation of T. cruzi from replicative non-infectious epimastigotes to non-replicative...

Introduction Proteolysis is an essential tool in regulating cellular functions at the post-translational level. The yeast Saccharomyces cereviszize serves as an excellent model organism for studying the biological role of proteolysis in the eukaryotic cell as it is accessible to the combination of biochemical, genetic and molecular biological techniques [ 1-31. As found for mammalian cells, two...