Wilson G A, Bott K F
J Bacteriol. 1968 Apr;95(4):1439-49. doi: 10.1128/jb.95.4.1439-1449.1968.
Cultures of Bacillus subtilis developed competence for the uptake of deoxyribonucleic acid in a chemically defined medium with a predictable, reproducible pattern. The gross effects of individual amino acids were determined. Seven amino acids, most of which are reported to be major components of the cell wall, were shown to impair the development of maximal levels of competence. When the synthetic growth medium was supplemented with a mixture of the nine amino acids which we found to stimulate the development of competence, the level of transfection was increased to 10 to 15% of the population. The actual level of competence in these populations was assayed by transformation of unlinked bacterial markers and by two different transfection assays. The results indicate that calculations from cotransfer of unlinked markers overestimates the degree of competence in highly competent populations of B. subtilis, whereas the number of plaques obtained in transfection is an under-estimate of the actual level of competence. The results are interpreted to indicate that neither method of analysis gives a true estimate of the competent population, but that more than 80% of the cells may be competent.
枯草芽孢杆菌在化学成分明确的培养基中以可预测、可重复的模式发展出摄取脱氧核糖核酸的能力。测定了单个氨基酸的总体影响。七种氨基酸（其中大多数据报道是细胞壁的主要成分）显示会损害最大能力水平的发展。当在合成生长培养基中添加我们发现能刺激能力发展的九种氨基酸混合物时，转染水平提高到群体的10%至15%。通过未连锁细菌标记的转化和两种不同的转染测定法来测定这些群体中的实际能力水平。结果表明，从不连锁标记的共转移计算得出的结果高估了枯草芽孢杆菌高能力群体中的能力程度，而转染中获得的噬菌斑数量则低估了实际能力水平。结果被解释为表明这两种分析方法都不能给出能力群体的真实估计，但超过80%的细胞可能具有能力。
