THE EFFECT OF SODIUM TETRADECYL SULFATE ON MOBILITY AND ANTIGEN DETECTABILITY OF MICROTUBULE PROTEINS IN SODIUM DODECYL SULFATE-POLYACRYLAMIDE GEL-ELECTROPHORESIS

Several factors been reported to influence the mobility of polypeptide in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAG E) including the brand of SDS. Using microtubule proteins from axoneme s of Lytechinus pictus and Spisula solidissima sperm and meiotic spind les of Spisula solidissima we demonstrate that the change in mobility was caused by sodium tetradecyl sulfate (STS), a major contaminant of many commercial SDS brands. We also examined the use of sodium tetrade cyl sulfate and different SDS brands as a tool in extracting more info rmation from immunoblot studies. Commercial SDS containing contaminant s other than sodium tetradecyl sulfate reduced or eliminated the immun osignal from certain polypeptides and the loss of antigenicity could n ot even be recovered by immunoblot under ''renaturing'' conditions. It can thus be concluded that STS can be useful in separating and identi fying comigrating polypeptides and in detecting additional immunobands in immunoblots.