32P-End-labeled restriction fragments derived from pBR322 and pUC9 DNAs were reacted with d-glucosamine or d-glucosamine-6-phosphate in the presence of Cu2+, and, after being heated at 90°C in aqueous piperidine, the DNA products were analyzed on polyacrylamide gels for the sequence-specificity of alkali-labile cleavaged sites. The intensity of oligonucleotide bands of cleavaged sites was directly proportional to the concentration of aminosugars, indicating that the DNA cleavage was caused by the action of aminosugars themselves. The preferred DNA cleavage sites induced by these aminosugars were identical, both at pyrimidine-purine (5′ → 3′) sequences, especially at thymine-guanine ones, and to some extent at pyrimidine-pyrimidine (5′ → 3′) sequences. The 6-phosphate moiety of d-glucosamine did not affect the specificity of DNA cleavage. © 1990 by the Japan Society for Bioscience, Biotechnology, and Agrochemistry. All rights reserved.
