albumin - publications

Predict more albumin - ligand interactions now!

1. Chem Res Toxicol. 2012 May 16. [Epub ahead of print]

Cys34 Adducts of Reactive Oxygen Species in Human Serum Albumin.

Grigoryan H, Li H, Iavarone AT, Williams ER, Rappaport SM.

Long-term exposures to reactive oxygen species (ROS) have been linked to scores
of chronic diseases. This has motivated interest in oxidation products of the
only free cysteine residue (Cys34) of human serum albumin (HSA) as possible
biomarkers of ROS exposure. However, Cys34 oxidation products have not been
detected in human serum or plasma. Using liquid chromatography-high resolution
tandem mass spectrometry, we report accurate masses and molecular compositions of
Cys34 oxidation products in the 2432 Da peptide resulting from tryptic digestion
of HSA. Peptides containing the expected sulfinic (Cys-SO2H) and sulfonic
(Cys-SO3H) acids, as well as an adduct representing addition of one oxygen atom
and loss of two hydrogen atoms, were detected in four archived samples of human
plasma and one fresh sample of human serum. We speculate that this latter adduct
is a sulfinamide formed by intramolecular reaction between either the Cys34
sulfenic acid (Cys-SOH) or sulfinic acid (Cys-SO2H) and the adjacent glutamine
residue (Gln33). All three Cys34 adducts were measured in the five human samples
with levels decreasing in the order sulfinic acid > (proposed) sulfinamide >
sulfonic acid. Parallel measurements of a negative control detected only small
amounts of the Cys34 sulfonic acid and the (proposed) sulfinamide and did not
detect the sulfinic acid.

PMID: 22591159 [PubMed - as supplied by publisher]