Nonspecific interactions alter lipopolysaccharide patterns and protein mobility on sodium dodecyl sulfate polyacrylamide gels

Authors

Aidong Yuan, University of Nebraska-LincolnFollow
R L. PardyFollow
Catherine P. Chia, University of Nebraska-LincolnFollow

Date of this Version

March 1999

Comments

Published in Electrophoresis 20 (1999), pp. 1946–1949. Copyright © 1999 WILEY-VCH Verlag GmbH. Used by permission. www.interscience.wiley.com/jpages/0173-0835

Abstract

In testing whether bacterial lipopolysaccharide (LPS) was a natural substrate for an esterase from the soil amebae Dictyostelium discoideum, we observed altered banding patterns of the LPS and changed protein mobility on sodium dodecyl sulfate (SDS) polyacrylamide gels after incubation of LPS with the enzyme. The initial interpretation of these results was that the enzyme had removed ester-linked acyl chains from the LPS, leading to a change in its migration on gels. However, esterase inactivated by treatment with either dithiothreitol (DTT), heat, or SDS generated the same mobility shifts. Bovine serum albumin (BSA) also induced the same change in the electrophoretic pattern. We conclude that the altered LPS patterns and protein mobility on SDS gels were caused by nonspecific interactions between LPS and protein.