Martin J H, Savage D C
Department of Microbiology, University of Illinois, Urbana, 61801.
Appl Environ Microbiol. 1988 Jun;54(6):1619-21. doi: 10.1128/aem.54.6.1619-1621.1988.
High-molecular-weight chromosomal DNA from Roseburia cecicola, an oxygen-intolerant anaerobe, could be isolated only when the bacterial cells were kept under anaerobic conditions up to the time of cell lysis. When the cells were exposed to oxygen before lysis, the chromosomal DNA degraded. Likewise, linear but not covalently closed circular DNAs degraded in cell extracts of the organism that were exposed to atmospheres containing O2 but not in extracts that were maintained in a reduced state. Covalently closed circular DNAs were nicked but not degraded in the oxidized extracts.
来自耐氧厌氧菌盲肠罗氏菌的高分子量染色体DNA，只有在细菌细胞直至细胞裂解时都保持在厌氧条件下才能分离出来。当细胞在裂解前暴露于氧气中时，染色体DNA会降解。同样，线性而非共价闭合环状DNA在暴露于含O2的大气中的该生物体细胞提取物中会降解，但在保持还原状态的提取物中不会降解。共价闭合环状DNA在氧化提取物中会被切口但不会降解。
