[Effect of chitosan oligomer on phage particles and reproduction of phage 1-97A in Bacillus thuringiensis culture].

The causes of bacteriophage 1-97A inactivation by the chitosan oligomer with a polymerization degree of 15 and the influence of the oligomer on the phage reproduction in the culture of Bacillus thuringiensis subsp. galleriae, strain 1-97, were studied. The study of the inactivation kinetics showed that, in 1 h, virtually all chitosan was bound to the phage particles, causing, as evidenced by electron microscopy, DNA release from the phage head, destruction of the phage particles, and agglutination of the phage particles or of their tails in the region of the endplate.

[Effect of chitosan derivatives on the development of phage infection in cultured Bacillus thuringiensis].

The influence of chitosan fragments with different degrees of polymerization and some chemical chitosan derivatives on the infection of Bacillus thuringiensis by phage 1-97A was studied. It was shown that chitosan inhibits phage infection and inactivates phage particles. The extent of inhibition of phage infection inversely depended on the degree of polymerization of chitosan fragments.

[Coliphages inactivation using chitosan derivatives].

The effect of chitosan fragments with different degrees of polymerization and the chemical derivatives of chitosan differing in the number of amino groups and total molecule charge on phages T2, T4, and T7 was studied. The interaction of chitosan with bacteriophage particles inactivated them to the extent dependent on the chemical properties of chitosan and its concentration. Phage T2 was found to be most susceptible to inactivation by chitosan.

[Effect of chitosan derivatives on the reproduction of Coliphages T2 and T7].

The effect of chitosan derivatives with different degrees of polymerization and deamination, as well as of chitosan 6-O-sulfate and chitosan N-succinate-6-O-sulfate, on the reproduction of coliphages T2 and T7 in Escherichia coli and on the growth of this bacterium was studied. Chitosan derivatives decreased the yield of coliphages and exhibited bactericidal activity. The efficiency of inhibition of viral infection and the bactericidal activity of chitosan were found to be dependent on the degree of its polymerization.

[Inhibition of phagolysis in a Bacillus thuringiensis culture by chitosan].

The ability of chitosan (poly-D-glucosamine) and two chitosan salts to prevent the phagolysis of Bacillus thuringiensis subsp. galleriae strain 1-97 was studied. Chitosan and its salts inhibited the productive infection caused by two nonrelated bacteriophages 1-97A and 1-97B and suppressed the culture lysis upon spontaneous prophage induction.