Kantor G J
J Bacteriol. 1972 Dec;112(3):1264-9. doi: 10.1128/jb.112.3.1264-1269.1972.
Difficulties were experienced in obtaining reproducible results for the sedimentation in alkaline sucrose gradients of Haemophilus influenzae deoxyribonucleic acid (DNA). The technique of McGrath and Williams of lysing whole cells on top of an alkaline sucrose gradient was employed. The addition of 0.2% sodium lauryl sulfate to the 0.2 n NaOH lysing solution and reduction of the hemin concentration in the growth medium increased the reproducibility to 100% for log-phase cells handled in a manner mimicking the handling procedure used for irradiating cells with ultraviolet light. Distributions of DNA with number average molecular weights of 200 x 10(6) were routinely obtained by using these modifications.
在获得流感嗜血杆菌脱氧核糖核酸(DNA)在碱性蔗糖梯度中的可重复沉降结果时遇到了困难。采用了McGrath和Williams在碱性蔗糖梯度顶部裂解全细胞的技术。在0.2N NaOH裂解溶液中添加0.2%的十二烷基硫酸钠,并降低生长培养基中的血红素浓度,对于以模拟紫外线照射细胞的处理程序处理的对数期细胞,可重复性提高到了100%。通过使用这些改进方法,常规获得了数均分子量为200×10⁶的DNA分布。