NMR analysis of neutrophil activation in sputum samples from patients with cystic fibrosis.

Disorders of the respiratory system, such as cystic fibrosis (CF), involve the infiltration and activation of airway inflammatory cells, including neutrophils. This leads to the secretion of peroxidases, which react further with substrates in solution to produce oxidative metabolites, such as 3-chlorotyrosine. Elevated levels of modified tyrosine residues in the airways of patients with CF may be detectable by nuclear magnetic resonance (NMR) in correlation with inflammatory cell influx.

Investigation of the role of the histidine-aspartate pair in the human exonuclease III-like abasic endonuclease, Ape1.

Hydrogen bonded histidine-aspartate (His-Asp) pairs are critical constituents in several key enzymatic reactions. To date, the role that these pairs play in catalysis is best understood in serine and trypsin-like proteases, where structural and biochemical NMR studies have revealed important pK(a) values and hydrogen bonding patterns within the catalytic pocket. However, the role of the His-Asp pair in metal-assisted catalysis is less clear.

The effects of Ca(2+) binding on the conformation of calbindin D(28K): a nuclear magnetic resonance and microelectrospray mass spectrometry study.

Calbindin D(28K) is a six-EF-hand calcium-binding protein found in the brain, peripheral nervous system, kidney, and intestine. There is a paucity of information on the effects of calcium binding on calbindin D(28K) structure. To further examine the mechanism and structural consequences of calcium binding to calbindin D(28K) we performed detailed complementary heteronuclear NMR and microelectrospray mass spectrometry investigations of the calcium-induced conformational changes of calbindin D(28K).