arthrobotrysamerospora (atcc 34468) produced glucoamylase in a semi-synthetic medium containing starch as a sole carbon source. polyacrylamide gel electrophoresis of crude glucoamylase showed three isoenzymes. they were designated as glu i, glu ii and glu iii according to their electrophoretic mobility. these iso-glucoamylases were purified by column chromatography using deae-sephadex a-50. the...

Pyruvate kinase activity in serum from presumably healthy individuals is labile, but can be maintained for a week when samples are stored frozen. Contrary to published data our electrophoretic and isoelectrofocusing studies with fresh sera show the presence of both K and M isoenzymes; the latter predominates. In freezer-stored serum the putative M isoenzyme showed a progressive decrease in pl v...

The blood serum (1) and plasma (2) proteins of various relatively easily accessible animals have been studied previously by the electrophoretic technique. The serum proteins of each species were found to give characteristic species variations in mobility, amount, and number of protein components. An electrophoretic study of the blood serum proteins of various animals of relatively lower phyloge...

Starch-gel electrophoresis of leukocyte alkaline phosphatases, rendered soluble by treating normal leukocytes with butanol, revealed three electrophoretic variants of the enzyme. The phosphatases in similarly prepared extracts of leukemia cells differed from the normal isozymes in electrophoretic. mobility. A single variant was detected in one case of untreated leukemia; a similar component and...

Counterion-induced inversion of the DNA charge was characterized through extensive molecular dynamics simulations. We observed reversal of the DNA motion in an external electric field upon increasing the concentration of trivalent or quadrivalent counterions. In the case of a divalent electrolyte, inversion of the DNA's electric charge was observed at high concentrations of the electrolyte but ...

We report an alternative method for electrophoretic separation of large DNAs using steric confinement between solid walls, without gel or obstacles. The change of electrophoretic mobility vs confinement thickness is investigated using fluorescence video microscopy. We observe separation at small confinement thicknesses followed by a transition to the bulk behavior (no separation) at a thickness...

Early membrane events in erythroid differentiation were investigated by means of cell electrophoresis utilizing cultured Friend erythroleukemia cell clones of different inducibility. The cell electrophoretic mobility decreased by 18% within 30 min of treatment with 1.5% dimethyl sulfoxide (DMSO) in highly inducible clones but not in noninducible clones. The reduced mobility persisted for 5 days...

This study is comprised of the synthesis and characterization of uniform fine particles of iron oxide in different shapes and sizes. Varying amounts of iron (III) chloride and sodium dihydrogen phosphate was heated at 98 oC for various periods, following the forced hydrolysis method. Scanning electron microscopic analysis showed that the shape and size of the precipitated particl...

Measurements of the mass and surface charge of microparticles are employed in the characterization of many types of colloidal dispersions. The suspended microchannel resonator (SMR) is capable of measuring individual particle masses with femtogram resolution. Here, we employ the high sensitivity of the SMR resonance frequency to changes in particle position, relative to the cantilever tip, to d...