Several specific modifications, both proteolytic and chemical, have been performed on RNase A. The ability of each of these RNase A derivatives to bind the human placental RNase inhibitor has been determined in competition binding assays. The interaction depends upon the native conformation of the enzyme. Loss of active site residues His-12 and His-119, along with auxiliary residues Lys-7, Phe-...

The mutant plant of Flaveria linearis characterized by Brown et al. (Plant Physiol. 81: 212-215) was studied to determine the cause of the reduced sensitivity to O(2). Analysis of CO(2) assimilation metabolites of freeze clamped leaves revealed that both 3-phosphoglycerate and ribulose 1,5-bisphosphate were high in the mutant plant relative to F. linearis with normal O(2) sensitivity. The k(cat...

INTRODUCTION Haemoglobin A1c (HbA1c) is a key analyte for the monitoring of glycemic balance in diabetic patients and is used for diabetes diagnosis in many countries. The potential interference of carbamylated haemoglobin (cHb) and labile glycated haemoglobin (LA1c) on HbA1c assays must remain a matter of vigilance. Such a situation has occurred in our laboratory with a kit replacement on the ...

The consequences of light adaptation and acclimation of photosynthesis on photosynthetic nitrogen use efficiency (NUE), particularly as it relates to the efficiency of ribulose-1,5-bisphosphate carboxylase (Rubisco) use in photosynthetic CO2 assimilation, was studied in the sun species Glycine max and the shade species Alocasia macrorrhiza. Both G. max and A. macrorrhiza were found to possess t...

Bronchiectasis (BR) and smoking are risk factors for rheumatoid arthritis (RA) development. The mechanisms by which smoking and BR trigger RA are unknown, but are associated with concurrent rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibody (anti-CCP) positivity. Anti-carbamylated protein antibodies (anti-CarP) have also been observed in BR patients and can be induced by smok...

Apolipoprotein A-1 (apoA-1) is the principal protein fraction of high-density lipoprotein (HDL), conferring to the latter many of its pleiotropic atheroprotective functions. After its effect on cholesterol efflux, the second most studied feature of apoA-1 is its anti-inflammatory property. In addition, it interferes with lipid peroxidation and innate immune receptors. These anti-inflammatory ef...

Tryptic hydrolysates of native, denatured, or chemically modified phosphoglucose isomerase from rabbit skeletal muscle were subjected to standard peptide mapping techniques. Maps prepared from hydrolysates of either native, guanidine hydrochloride-denatured, or carboxymethylated enzyme were found to have only two-thirds to three-fourths of the number of ninhydrin-positive spots that would be ex...

BACKGROUND Hemoglobin (Hb) heterogeneity arises mainly from posttranslational modifications of the globin chains, and cation-exchange chromatography reveals falsely increased concentrations of some minor Hbs in the presence of abnormal Hbs. Here we describe a method for identification of the globin chains and their posttranslational modifications contained in the Hb fractions. METHODS We used...

The present review touches on a long-lasting debate on possible artefacts (i.e. generation of spurious spots, not belonging to the biological sample under analysis) induced by the separation technique (in this case, two-dimensional mapping) per se. It is shown here that some of the biggest offenders, always blamed in the past (at least since 1970, i.e. since the inception of gel-base isoelectri...

De novo peptide sequencing by mass spectrometry represents an important strategy for characterizing novel peptides and proteins, in which a peptide's amino acid sequence is inferred directly from the precursor peptide mass and tandem mass spectrum (MS/MS or MS(3)) fragment ions, without comparison to a reference proteome. This method is ideal for organisms or samples lacking a complete or well-...