Assuntos
Cromatografia em Camada Fina/métodos , Histidina/análogos & derivados , Proteínas Quinases , Proteínas de Saccharomyces cerevisiae , Animais , Autorradiografia , Bovinos , Eletroforese em Gel de Poliacrilamida , Proteínas Fúngicas/isolamento & purificação , Glutationa Transferase/metabolismo , Histidina/análise , Peptídeos e Proteínas de Sinalização Intracelular , Espectrometria de Massas , Núcleosídeo-Difosfato Quinase/isolamento & purificaçãoRESUMO
Posttranslational phosphorylation of proteins is an important event in many cellular processes. Whereas phosphoesters of serine, threonine and tyrosine have been extensively studied, only limited information is available for other amino acids modified by a phosphate group. The formation of phosphohistidine residues in proteins has been discovered in prokaryotic organisms as well as in eukaryotic cells. The ability to biochemically analyze phosphohistidine residues in proteins, however, is severely hampered by its extreme lability under acidic conditions. In our studies we have found that by replacing the phosphate linked to the histidine residue with a thiophosphate, a phosphohistidine derivative with increased stability is formed. This allows the analysis of phosphohistidine-containing proteins by established biochemical techniques and will greatly aid in the investigation of the role of this posttranslational modification in cellular processes.
Assuntos
Histidina/metabolismo , Sequência de Aminoácidos , Cromatografia em Camada Fina , Histidina/análogos & derivados , Histidina/química , Fosforilação , Processamento de Proteína Pós-TraducionalRESUMO
A patient with intractable malignant ascites from metastatic tabular breast carcinoma underwent insertion of a Tenckhoff catheter in July 1997. Seventeen months later the patient continues to have excellent symptomatic relief, without complications, by self-drainage of ascites at home. Tenckhoff catheter can be useful in the management of intractable malignant ascites.
