Interaction of DNA with guanidylated BPTI.

It was shown that guanidylated BPTI complexed with DNA stablized the native structure of the latter. It was found that hyperchromism values of DNA-guanidylated BPTI complexes, dialyzed against increasing and redialized against decreasing concentrations of NaCl or urea, amount ot ca 50% of hyperchromism values of free DNA or nondialyzed complexes. All three geometric forms of DNA were detected in DNA-guanidylated BPTI complexes subjected to the transient action of NaCl or urea.