Inhibition of protein carbamylation in urea solution using ammonium-containing buffers

Ion exchange chromatography of prolactin in urea-containing buffers.

Moore and Stein (1) have reviewed the work of Boardman and Partridge and others on problems encountered in attempting the chromatography of nonbasic proteins on Amberlite IRC-50 by elution analysis with the use of buffers of constant composition for the elution. Boardman and Partridge (2) suggested that the difficulty in achieving reversible equilibrium binding was due to hydrogen bonding betwe...

Direct Determination of Cyanate in a Urea Solution and a Urea-Containing Protein Buffer

Urea and protein carbamylation in ESRD: Surrogate markers or partners in crime?

Protein carbamylation may result from chronic exposure to elevated levels of urea in patients with chronic kidney disease. Carbamylation could cause conformational changes in proteins resulting in alterations in binding sites and disturbances in cellular functions. Elevated levels of carbamylated protein have been shown to be associated with increased risk of death from cardiac causes in patien...

Protein Carbamylation and Cardiovascular Disease

Carbamylation constitutes a posttranslational modification of proteins or amino acids and results from different pathways in vivo. First is the non-enzymatic reaction between isocyanic acid, a decomposition product of urea, and either the N-terminus or the ɛ-amino group of lysine residues. Isocyanic acid levels, while low in vivo, are in equilibrium with urea and are thus increased in chronic a...

The Validity of the Glass Electrode in Ammonium Chloride Buffers

It is shown that the glass electrode may be used without appreciable error to measure pH of ammonia or ammonium chloride buffers, but that corrections must be applied above pH 8.6 if sodium ions are present in the unknown solution. Corrections are given for values from pH 8.6 to 9.4. A slight further modification of form of glass electrode used by previous workers is described.