4 chloro 7 nitrobenzofurazane nbd cl

Human Lactoferrin (LF) recombinant, expressed in rice, Iron saturated, ≥ 90% (SDS-PAGE), Human Lactoferrin partially iron saturated (LF_p iron saturation ~ 0.07%) recombinant, expressed in rice, ≥ 90% (SDS-PAGE), dithiothreitol (DTT), urea, ethylendiamminotetraacetic acid (EDTA), 5,5′-dithiobis (2-nitrobenzoic acid) (DTNB), 1-chloro-2,4-dinitrobenzene (CDNB), 4-chloro-7-nitrobenzofurazane (NBD-Cl), N-acetyl-L-tryptophanamide (NATA), bromopyruvic acid (BrP), cystamine, cystine, homocystine, oxidized glutathione (GSSG), and ammonium bicarbonate (AMBIC) was from Sigma-Aldrich (St. Louis, MO, USA). Water and formic acid (FA), LC–MS grade, were from Merck (Darmstadt, Germany). Trypsin enzyme (Gold MS Grade) was from Promega (Madison, WI, USA). Acetonitrile (ACN) (LC–MS grade) was from Merck (Darmstadt, Germany).

α-Chymotrypsinogen A (ChTg) from bovine pancreas. The protein was tested for purity by using an FPLC system (Amersham-Pharmacia, Sweden) equipped with a column Superose-12 (data not shown). Bromopyruvic acid (BrP), cystamine, L-cysteine (Cys), 1-chloro-2,4-dinitrobenzene (CDNB), 5,5′-dithiobis(2-nitrobenzoic acid) (DTNB), dithiothreitol (DTT), ethylendiamminotetreaacetic acid (EDTA), L-glutathione (GSH), oxidized glutathione (GSSG), homocystine, N-acetyl-L-tryptophanamide (NATA), 4-chloro-7-nitrobenzofurazane (NBD-Cl), and all other reagents were from Sigma-Aldrich (St. Louis, Mo, USA). GSH solutions were freshly prepared and the amount of GSSG was less than 1% as assayed by standard analytical procedures.