Optimized sample preparation for two-dimensional gel electrophoresis of soluble proteins from chicken bursa of Fabricius

Table 1 Component of five different extraction buffers

Extraction buffer	Components^a
extraction buffer I	9 M urea, 4% (w/v) CHAPS, 65 mM DTT, 0.2% Bio-Lyte 3/10, 1 mM PMSF, 20 U/ml DNase I, 0.25 mg/ml RNase A
extraction buffer II	7 M urea, 2 M thiourea, 4% (w/v) CHAPS, 65 mM DTT, 0.2% Bio-Lyte 3/10, 1 mM PMSF, 20 U/ml DNase I, 0.25 mg/ml RNase A
extraction buffer III	7 M urea, 2 M thiourea, 2% (w/v) CHAPS, 65 mM DTT, 0.2% Bio-Lyte 3/10, 1 mM PMSF, 20 U/ml DNase I, 0.25 mg/ml RNase A
extraction buffer IV	7 M urea, 2 M thiourea, 2% (w/v) CHAPS, 50 mM DTT, 0.2% Bio-Lyte 3/10, 1 mM PMSF, 20 U/ml DNase I, 0.25 mg/ml RNase A
extraction buffer V	7 M urea, 2 M thiourea, 2% (w/v) CHAPS, 50 mM DTT, 40 mM Tris, 0.2% Bio-Lyte 3/10, 1 mM PMSF, 20 U/ml DNase I, 0.25 mg/ml RNase A

^aCHAPS, 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate; DTT, dithiothreitol; Tris, tris(hydroxymethyl)aminomethane; DNase I, Deoxyribonuclease I; RNaseA, Ribonuclease A; PMSF, Phenylmethylsulfonyl fluoride