Denaturing gradient gel electrophoresis (formamide with urea) has been used to study the melting of supercoiled DNA. A linear gradient of denaturant concentration proportional to a 25 degrees C linear increase of temperature (Teff) from the left to the right edge of the gel was created perpendicular to DNA migration. The mobility of supercoiled DNA molecules was shown to drop to the level of re...

Soils from the hyperarid Atacama Desert of northern Chile were sampled along an east-west elevational transect (23.75 to 24.70 degrees S) through the driest sector to compare the relative structure of bacterial communities. Analysis of denaturing gradient gel electrophoresis (DGGE) profiles from each of the samples revealed that microbial communities from the extreme hyperarid core of the deser...

A novel technique is reported for screening point mutations is genomic DNA: double gradient, denaturing gradient gel electrophoresis (DG-DGGE). Unlike conventional DGGE, which exploits a single gradient of denaturing chemicals (typically urea and formamide) along the migration path to force the two hetero- and two homo-duplexes to partially unwind and separate, DG-DGGE superimposes a second (po...

A procedure for high resolution electrophoresis of isozymes of the mosquito Aedes aegypti using nonlinear (2.5%-20%) polyacrylamide gradient gel slabs is described. Crude mosquito homogenates were electrophoresed on gradient and on homogeneous (7%) polyacrylamide gels and stained for esterase (EST), isocitrate dehydrogenase (IDH) and malate dehydrogenase (MDH). The resulting zymograms were comp...