Table 2.

Solutions and buffers used to extract the root proteins * from cowpea genotype CE-31 for two-dimensional polyacrylamide gel electrophoresis (2D-SDS-PAGE) analysis.

(1)50 mM pyridine + 10 mM thiourea + 1% (m/v) SDS + 100 M HCl, pH 5.0

(2)50 mM pyridine + 10 M thiourea + 1% (m/v) SDS + 100 M HCl, pH 5.0, + 1:2 (m/v) polyvinylpolypyrrolidone (PVPP)

(3)20 mM Tris-HCl pH 6.0, containing 20% (v/v) glycerol + 3% (v/v) polyethylene glycol (PEG)

(4)20 mM Tris-HCl pH 6.0, containing 20% (v/v) glycerol, 3% (v/v) PEG, 1:2 (m/v) PVPP

(5)40 mM Tris-HCl pH 7.0, containing 250 mM sucrose, 1% (v/v) triton X-100, 10 mM ethylenediaminetetraacetic acid (EDTA), 1.0 mM DTT, 1.0 mM phenylmethylsulfonyl fluoride (PMSF)

(6)40 mM Tris-HCl pH 7.0, containing 250 mM sucrose, 1% (v/v) Triton X-100, 10 mM EDTA, 1.0 mM dithiothreitol (DTT), 1.0 mM PMSF, 1:2 (m/v) PVPP

(7)100 mM Tris-HCl pH 8.0, containing 20% (v/v) glycerol, 3% (v/v) PEG

(8)100 mM Tris-HCl pH 8.0, containing 20% (v/v) glycerol, 3% (v/v) PEG, 1:2 (m/v) PVPP.

(9)100 mM Tris-HCl pH 8.0, containing 20% (v/v) glycerol, 3% (v/v) PEG, 1:2 (m/v) PVPP, 10 mM EDTA, 1.0 mM DTT, 1.0 mM PMSF

(10)100 mM Tris-HCl pH 9.0, containing 0.01 M EDTA, 1% (v/v) Triton X-100

(11)100 mM Tris-HCl pH 9.0, containing 0.01 M EDTA, 1% (v/v) Triton X-100, 1:2 (m/v) PVPP

* The proportion of cowpea genotype CE-31 root powder to solutions/buffers was 1:2 (m/v).