Smith Stephanie A, Wang Yan, Morrissey James H
Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA.
Current address: Bayer Pharmaceuticals, San Francisco, CA, USA.
Electrophoresis. 2018 Oct;39(19):2454-2459. doi: 10.1002/elps.201800227. Epub 2018 Jul 26.
PAGE is often used to resolve inorganic polyphosphates (polyP), but unfortunately polyP size ladders are not commercially available. Since several dyes that are commonly used to detect nucleic acids in gels also stain polyP, we examined the utility of commercially available DNA size ladders for estimating polyP polymer lengths by gel electrophoresis. Narrow size fractions of polyP were prepared and their polymer lengths were quantified using NMR. Commercially available DNA ladders and these polyP fractions were then subjected to PAGE to determine the relationship between migration of DNA vs polyP, which was found to be: log (dsDNA length in bp) = 1.66 × log (polyP length in phosphate units) - 1.97. This relationship between DNA and polyP size held for a variety of different polyacrylamide concentrations, indicating that DNA size ladders can readily be employed to estimate polyP polymer lengths by PAGE.
聚丙烯酰胺凝胶电泳（PAGE）常用于分离无机多聚磷酸盐（polyP），但遗憾的是，多聚磷酸盐分子量标准物并无市售。由于常用于检测凝胶中核酸的几种染料也能使多聚磷酸盐染色，因此我们研究了市售DNA分子量标准物在通过凝胶电泳估计多聚磷酸盐聚合物长度方面的实用性。制备了窄分子量范围的多聚磷酸盐组分，并使用核磁共振（NMR）对其聚合物长度进行了定量。然后将市售DNA分子量标准物和这些多聚磷酸盐组分进行聚丙烯酰胺凝胶电泳，以确定DNA与多聚磷酸盐迁移率之间的关系，结果发现：log（双链DNA长度，单位为碱基对）= 1.66×log（多聚磷酸盐长度，单位为磷酸基团） - 1.97。DNA与多聚磷酸盐大小之间的这种关系在各种不同的聚丙烯酰胺浓度下均成立，这表明DNA分子量标准物可很容易地用于通过聚丙烯酰胺凝胶电泳估计多聚磷酸盐聚合物的长度。
