Evidence that the glutamine synthetase dodecamer from Escherichia coli is comprised of 12 identical subunits of molecular weight 49,000 has been obtained by end group analysis. Application of the carbamylation procedure to the NH*terminal analysis revealed only serine. The yield was 98% of that expected from a polypeptide of the size proposed for the monomeric species. The following partial seq...

Positive charge at lysine residues of hen egg white lysozyme (HEWL) was neutralized through carbamylation reaction and its effect on the conformational stability of the enzyme was studied. Additionally, guanidination of HEWL was also performed, in which the modified derivative retained the positive charge at lysine residues, but with the addition of guanidino group. About 88% and 85% of lysine ...

The regulation of Rubisco activity was investigated under high, constant photosynthetic photon flux density during the diurnal phases of Crassulacean acid metabolism in Kalanchoë daigremontiana Hamet et Perr. During phase I, a significant period of nocturnal, C(4)-mediated CO(2) fixation was observed, with the generated malic acid being decarboxylated the following day (phase III). Two periods ...

BACKGROUND Carbamylation is an irreversible process of non-enzymatic modification of proteins by the breakdown products of urea. For haemoglobin (Hb), the extent of carbamylation is a marker of urea exposure and has been proposed as an indicator of the control of uraemia by dialysis, analogous to the use of Hb glycosylation in diabetic patients. METHODS We performed a cross-sectional study of...

We developed a continuous-addition method for maintaining subsaturating concentrations of ribulose-1,5-bisphosphate (RuBP) for severa1 minutes, while simultaneously monitoring i t s consumption by ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). This method enabled us to observe the effects of subsaturating RuBP and CO, concentrations on the activity of Rubisco during much longer peri...

The posttranslational modification of proteins has the potential to generate neoepitopes that may subsequently trigger immune responses. The carbamylation of lysine residues to form homocitrulline may be a key mechanism triggering inflammatory responses. We evaluated the role of carbamylation in triggering immune responses and report a new role for this process in the induction of arthritis. Im...

Carbamylation is a post-translational modification, the pathophysiological consequences of which remain poorly understood. MicroRNAs (miRNAs) are endogenous non-coding small ribonucleic acids that have emerged as one of the central players in gene expression regulation. This study was designed to determine the effect of carbamylated albumin (cAlb) on the expression of miRNAs. Albumin was carbam...