Soluble Polyacrylamide Research Articles

Resistance of chromatin superstructure to tryptic digestion modulated by conjugated polyacrylamide

Soluble polyacrylamide conjugates have been used to modulate tryptic digestion of chromatin. Digestion of histones H 1/H 5 and H 3 are mutually dependent and relatively independent of that of the core histones which are not significantly digested until 50–60% of H 3 is degraded. H 1/H 5 and H 3 are most exposed, H 3 behaves as a ‘non-core’ histone, its destruction appears to be the critical factor in the collapse of the chromatin superstructure during tryptic digestions. The digestion kinetics are explained by proposing that the initial sites of attack are in cavities much larger than the diameter of trypsin (4–5 nm). Procedures for the preparation of soluble polyacrylamide and its conjugation to trypsin are described.

Immobilization and characterization of Saccharomyces cerevisiae in crosslinked, prepolymerized polyacrylamide-hydrazide

Baker's yeast (Saccharomyces cerevisiae) was immobilized in gels made of prepolymerized, linear, water soluble polyacrylamide, partially substituted with acylhydrazide groups. Gelation was effected by the addition of controlled amounts of dialdehydes (e.g. glyoxal). The immobilized yeasts retained full glycolytic activity. Moreover, the entrapped cells were able to grow inside the chemically corsslinked gel during continuous alcohol production. Glyoxal was found to be the most favourable crosslinking agent for this system. the system employed allowed for the free exchange of substrate and products. The gel surrounding the entrapped cells had no effect on temperature stability profile. On the other hand, substantial enhancement in survival of cells in presence of high ethanol concentrations was recorded for the entrapped yeast. The capability of the immobilized yeast to carry out continuous conversion of glucose to ethanol was demonstrated.

A method for the recovery of nucleic acids from polyacrylamide gels

A method is described for the recovery of RNA from ethylene diacrylate cross-linked polyacrylamide gels. The RNA is recovered undergraded in good yields under mild conditions and is free of soluble polyacrylamide gels.

Acrylamide polymerization in concentrated aqueous solutions and in two-phase systems

A study was made of the polymerization of acrylamide (AA) in two-phase systems containing water and in concentrated aqueous solutions in presence of ammonia or caustic soda. It was found that polymers prepared by polymerization in these systems, when the latter contain not less than 0·5 wt.% caustic soda, or 1·3 wt.% ammonia, dissolve, completely in water. The rate of chain transfer through β,β′,β″-nitriletripropionamide molecules was determined. The probable causes of the formation of soluble polyacrylamide in concentrated aqueous systems in the presence of ammonia or caustic soda are analysed.