Jyssum K, Jyssum S
J Bacteriol. 1965 Dec;90(6):1513-9. doi: 10.1128/jb.90.6.1513-1519.1965.
Jyssum, Kaare (University of Oslo, Oslo, Norway), and Sidsel Jyssum. Variation in density and transformation potential in deoxyribonucleic acid from Neisseria meningitidis. J. Bacteriol. 90:1513-1519. 1965.-Three variants of Neisseria meningitidis have been examined with regard to competence. One is the genetically competent M1-12 his(-)cp(+), the second is the genetically incompetent M1-12 his(-)cp(-) which does not revert to competence, and the third is the incompetent mutant M1-18 his(-)gly(-)(cp) which reverts to competence. An examination of the relation between the deoxyribonucleic acid (DNA) and protein contents indicates the existence of more DNA in strain M1-12 his(-)cp(+) than in strain M1-12 his(-)cp(-). DNA prepared from the three strains was examined by density gradient centrifugation. The distribution of DNA in the gradients was unimodal. No significant differences could be observed between the distribution curves obtained from the three test strains. When the distribution in the gradients of transformation potential corresponding to five biochemical markers was measured, a pronounced difference was found among the three test strains. The distribution of the markers in the gradient from strain M1-12 his(-)cp(-) was unimodal. In the DNA from strain M1-18 his(-)gly(-)(cp), all the markers examined showed bipartite distribution curves with low relative specific transforming activity, corresponding to an area near the middle of the DNA distribution. The strain M1-12 his(-)cp(+) showed a similar bipartite distribution of four biochemical markers, whereas the marker pro had a very high relative specific transforming activity in the area where the other markers tested had a reduced activity. The nature of the DNA with reduced transformation potential which seems to be present in strains M1-12 his(-)cp(+) and M1-18 his(-)gly(-)(cp) is discussed in relation to previous observations. The possibility has been presented that the cp factor in N. meningitidis may be a true episome.
耶斯姆，卡雷（挪威奥斯陆大学，奥斯陆），以及西德尔·耶斯姆。脑膜炎奈瑟菌脱氧核糖核酸密度及转化潜力的变异。《细菌学杂志》90:1513 - 1519。1965年。——已对脑膜炎奈瑟菌的三个变体进行了感受态方面的检测。一个是基因上有感受态的M1 - 12 his(-)cp(+)，第二个是基因上无感受态且不会回复为感受态的M1 - 12 his(-)cp(-)，第三个是无感受态突变体M1 - 18 his(-)gly(-)(cp)，它会回复为感受态。对脱氧核糖核酸（DNA）与蛋白质含量之间关系的检测表明，M1 - 12 his(-)cp(+)菌株中的DNA比M1 - 12 his(-)cp(-)菌株中的更多。通过密度梯度离心法检测了从这三个菌株制备的DNA。DNA在梯度中的分布是单峰的。从这三个测试菌株获得的分布曲线之间未观察到显著差异。当测量对应于五个生化标记的转化潜力在梯度中的分布时，在这三个测试菌株之间发现了明显差异。来自M1 - 12 his(-)cp(-)菌株的梯度中标记的分布是单峰的。在来自M1 - 18 his(-)gly(-)(cp)菌株的DNA中，所有检测的标记都显示出二分分布曲线，相对比活性较低，对应于DNA分布中间附近的区域。M1 - 12 his(-)cp(+)菌株对四个生化标记显示出类似的二分分布，而标记pro在其他测试标记活性降低的区域具有非常高的相对比活性。结合先前的观察结果讨论了M1 - 12 his(-)cp(+)和M1 - 18 his(-)gly(-)(cp)菌株中似乎存在的转化潜力降低的DNA的性质。提出了脑膜炎奈瑟菌中的cp因子可能是真正附加体的可能性。
