In vivo observation of polypeptide flux through the bacterial chaperonin system

Article Abstract:

Researchers have investigated the flux of newly synthesized proteins through chaperonin GroEL in living E. coli cells and upon cell-free translation. It was established that only between 10% and 15% of all newly synthesized polypeptide chains interact with GroEL under nonstress conditions and transit the chaperonin extremely quickly. The extent to which the population of a particular protein interacts with GroEL in vivo is usually determined by its rate of folding, the cellular GroEL concentration and the affinity of its folding intermediates for GroEL.

Protein folding, Polypeptides, Protein metabolism

---

Crystal structure of an Hsp90-geldanamycin complex: targeting of a protein chaperone by an antitumor agent

Article Abstract:

A study of the crystal structure of an Hsp90-geldanamycin complex was conducted. The structure of the geldanamycin-binding domain of Hsp90 shows a pocket. When geldanamycin binds inside this pocket, a compact structure similar to that of a polypeptide chain in a turn conformation is adopted. The findings suggest that the pocket binds a part of the polypeptide substrate and is involved in the conformational maturation/refolding reaction.

Conformational analysis, Binding sites (Biochemistry), Active sites (Biochemistry), Cell lines, Antineoplastic antibiotics

---

A stress sensor for the bacterial periplasm

Article Abstract:

The stress response in bacteria, consisting of stress sensing and reaction in the periplasm is independent of the one found in cytoplasm. The activation of bacterial periplasmic stress sensor DegS is mediated by releasing the inhibition of its protease domain initiating a proteolysis cascade that leads to the synthesis of periplasmic chaperone proteins.

Germany, Brief Article, Physiological aspects, Stress (Physiology), Cellular signal transduction, Protein synthesis, Protein biosynthesis, Bacterial proteins, Enzyme activation

Similar abstracts:

• Abstracts: Biodegradation of naphthalene in aqueous nonionic surfactant systems. Succession of phenotypic, genotypic, and metabolic community characteristics during in vitro bioslurry treatment of polycyclic aromatic hydrocarbon-contaminated sediments
• Abstracts: Generation of a proton motive force by the anaerobic oxalate-degrading bacterium Oxalobacter formigenes. Routine procedures for isolation and identification of enterococci and fecal streptococci
• Abstracts: Purification and characterization of a keratinase from a feather-degrading Bacillus licheniformis strain. An altered Pseudomonas diversity is recovered from soil by using nutrient-poor Pseudomonas-selective soil extract media
• Abstracts: Expression of a cell adhesion molecule, Neuropilin, in the developing chick nervous system. A functional role for the middle extracellular region of the neural cell adhesion molecule (NCAM) in axonal fasciculation and orientation
• Abstracts: Cloning, expression, and purification of choline dehydrogenase from the moderate halophile Halomonas elongata

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.