Binding of Ampholine to transfer RNA

Solubilization of proteins for electrophoretic analyses

“…First, nucleic acids behave as polyanions and are therefore able to bind many proteins through electrostatic interactions. Second, this problem is even more severe when separation with isoelectric focusing is to be performed, as nucleic acids also bind carrier ampholytes to give complexes [21], that also bind proteins and focus to give completely artifactual results with a high amount of streaking [22]. Third, nucleic acids (especially DNA) are very long molecules that are able to increase the viscosity of the solutions considerably and also to clog the small pores of the polyacrylamide gels used to separate the proteins.…”

Purification of Pasteurella multocida antigens by ultracentrifugation and isoelectrofocusing

“…Ampholines binding to the phosphate groups of the 4 0 p antigens (Drysdale and Righetti 1972;Galante et al 1976) or possibly to the lipid moiety of the 4 0 p antigens (Phillips et al 1976) could cause this artifact.…”

A CTAB based method for the preparation of total protein extract of wine spoilage microrganisms for proteomic analysis

“…Digitalised images of 2D maps of CTAB treated samples were qualitatively compared with maps obtained with four other protocols described in the literature (use of usual buffer used for the 2D electrophoresis [12]; ampholines [13,14]; phenol:chloroform:isoamylic alcohol (25:24:1, v/v) [15] and treated with acidic extraction [4]). Table 2 compares the results by indicating the number of protein spots counted with the PDQuest Software (BioRad) on each set of maps.…”

“…Spot counted CTAB 507 ± 12 No treatment 357 ± 8 Ampholines 1% [13,14] 392 ± 11 Phenol:chloroform:isoamilic acid [15] 188 ± 13 Acidic extraction [4] 381 ± 4 methanol 30 min, washed twice with 3% acetic acid 20 min and kept in 1% periodic acid 3% acetic acid 20 min. Washed twice with 3% acetic acid and incubated 15 min in the dark with Schiff reagent.…”

“…Pellet obtained from cell lysates has been treated according to the following methods: (1) re-suspended in the usual buffer used for the 2D electrophoresis [12]; (2) treated with 1% ampholines pH 3-10 [13,14]; (3) treated with phenol:chloroform:isoamylic alcohol (25:24:1, v/v) as described for the removal of nucleic acid [15]; (4) treated with acidic extraction, as described in [4]. The proteins collected are re-suspended in the usual buffer used for the 2D electrophoresis (7 M urea, 2 M thiourea, 3% CHAPS, 40 mM Tris) and run as explained below.…”