The effects of polyamines on the melting of polyriboinosinic acid plus polyribocytidylic acid complex in solution

Inducement of respiratory mucosal immunogenicity for nasal vaccine due to amine- and amide-inactivation of parainfluenza virus type 1, Sendai

The protective effects in mice by nasal vaccination of amine- and amide-inactivated Sendai viruses were investigated by a contact exposure experiment, immunofluorescent examination of the entire respiratory tract, and checking the serum HI antibody development. Of 10 monoamines, ethanolamine and 2-methoxyethylamine vaccines induced complete protection, and methylamine, ethylamine, n-propylamine, n-butylamine, 2-ethoxyethylamine, diethylamine and triethylamine vaccines brought about almost complete protection or lower respiratory infection. The methoxyamine-treated mouse conferred the least protection. Of 5 diamines, 1,3-diaminopropane vaccine inhibited completely the infection, but hydrazine, ethylenediamine, putrescine, and cadaverine vaccines produced regional infection. Two polyamines, spermine and spermidine, did not inactivate the virus. Of 4 amides, only semicarbazide vaccine conferred complete mucosal defense, while acetamide, propionamide, and isonicotinic acid hydrazide vaccines lead to regional infection. Serum HI titers developed by vaccination were low on the whole, following their slight rise, fall or maintenance postexposure. In effect, the 4 vaccines inactivated by a best-suited interstrand cross-link between phosphate groups in helix of viral RNA brought about the strongest protection, and showed the necessity of a definite length of molecules for inactivants.

Use of polynucleotide/polyacrylamide-gel electrophoresis as a sensitive technique for the detection and comparison of ribonuclease activities

A technique is described in which the incorporation of a polynucleotide substrate into the matrix of a polyacrylamide gel allows the use of electrophoresis for the detection of polycationic ribonuclease activity rather than simply the presence of protein. Because use is made of the catalytic properties of ribonucleases, polynucleotide/polyacrylamide-gel electrophoresis is apparoximately 10(5) times more sensitive for the detection of these enzymes than conventional gel electrophoresis with the use of protein-staining dyes. Initial studies showed that the poor migration, in the gels, of highly charged polycationic ribonucleases in the presence of negatively charged synthetic polynucleotides could be overcome by high concentrations of spermine. The positively charged polyamine, by neutralizing the polyanionic polynucleotide, enabled these basic enzymes to migrate considerable distances in the gel. Electrophoresis of the RNAases under conditions of low pH, and incubation of the gel at neutral pH followed by staining for polynucleotide, resulted in coloured gels containing clear bands that define regions of enzyme activity. Alterations in spermine concentration or substrate identity caused changes in the positions of these bands, suggesting a dynamic interaction among the enzyme, polyamine and polynucleotide. Because of the advantages, in terms of selectivity and sensitivity of polynucleotide/polyacrylamide-gel electrophoresis, this technique was used to demonstrate the nuclease homogenity of three purified bovine muscle enzymes, and to compare these enzymes with each other, as well as with bovine pancreatic ribonuclease A.