DNA Nano- and Microparticles:New Products of Polymerase Chain Reaction

摘要

Polymerase chain reaction (PCR) is a method of in vitro amplification of specific DNA sequences with the use of a thermostable DNA polymerase [1]. Currently, PCR is widely used for molecular cloning, diagnosing genetic and infectious diseases, personal identification, as well as in other fields of science and medicine. It is believed that the major PCR product is a linear double-stranded DNA fragment flanked with two primers. We discovered that PCR with the KlenTaq polymerase also yields spherical nano- and microbodies consisting of pure DNA. In this study, we described the conditions under which DNA nano- and microparticles are formed and gave their primary characteristics. This study was performed with Saccharomyces cer-evisiae and Pichia pastoris strains from the collection of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences. DNA-con-taining cell walls or micromummies of yeast obtained as described in [2], DNA specimens isolated from yeast micromummies after incubation at 90℃ for 10-15 min and subsequent centrifugation [2], and purified genomic DNAs isolated using glass beads as described in [3] were used as templates for PCR.