Homogeneity of Envelope Proteins of Escherichia coli Separated by Gel Electrophoresis in Sodium Dodecyl Sulfate

摘要: Some envelope proteins of Escherichia coli show variable behavior in acrylamide gel electrophoresis 1% sodium dodecyl sulfate, depending upon the conditions solubilization. When solubilized sulfate at 70 C for 20 min, three distinct peaks (peaks 4, 6, and 7) are seen molecular weights 57,800, 44,300, 38,400, respectively. However, when fractions 100 5 or they treated with N, N-dimethylformamide acidic pH before solubilization by our method, only a single peak 48,000 weight is observed range mentioned above. That is, 4 7 disappear new appears position overlapping 6. Proteins isolated from similar shifts to treatment C. No other any change heat treatment. The increase completely accounted decrease 7, indicating that composed 7. it concluded these consist distinctly different following reasons: (i) have amino acid compositions, (ii) solubilities nonionic detergent, Nonidet P-40, as shown previously, (iii) 6 (protein Y) related deoxyribonucleic synthesis, (iv) resistance proteolytic enzymes. Although reasons anomalous not well understood present, important solubilize E. standard method order investigate their properties functions proteins.