Hoch J A, Barat M, Anagnostopoulos C
J Bacteriol. 1967 Jun;93(6):1925-37. doi: 10.1128/jb.93.6.1925-1937.1967.
The effects on transformation and transduction of an ultraviolet sensitivity (uvr(-)) and two ultraviolet sensitivity-recombination deficiency (rec-1(-) and rec-2(-)) mutations in isogenic strains of Bacillus subtilis were investigated. Transformation frequency in the rec-1(-) and rec-2(-) strains was reduced to approximately 5 and 25%, respectively, of the parental strains. Normal kinetics of deoxyribonucleic acid dose response in transformation were found for the rec-1(+) and rec-2(-) strains. Biphasic curves were obtained with the rec-1(-) strains. Transduction frequency with bacteriophage SP-10 decreased parallel to transformation frequency in the rec-1(-) and rec-2(-) strains. This result suggests that transformation and SP-10 transduction share a common mechanism for genetic recombination. It also indicates that the reduction in transformation frequency of these strains was not due to altered competence. Transduction frequency with bacteriophage PBS-1 or 3NT, on the contrary, was not diminished in rec-1(-) strains. This frequency was reduced in rec-2(-) strains but not as severely as that of transformation or SP-10 transduction. Several hypotheses to interpret these differences are presented. Recombination frequency between linked markers was reduced more than 50% in transformation by the presence of the rec-1(-) mutation. Linkage was unaffected in the rec-2(-) strains. Neither the rec-1(-) nor the rec-2(-) mutation had an effect on linkage in PBS-1 or 3NT transduction. The uvr(-) strains were transformed at a frequency equal to or greater than that of the parental strains. These strains were transduced by all bacteriophage systems at frequencies about twofold higher than those of parental strains.
研究了紫外线敏感性（uvr(-)）以及两个紫外线敏感性-重组缺陷（rec-1(-)和rec-2(-)）突变对枯草芽孢杆菌同基因菌株转化和转导的影响。rec-1(-)和rec-2(-)菌株的转化频率分别降至亲本菌株的约5%和25%。rec-1(+)和rec-2(-)菌株在转化中脱氧核糖核酸剂量反应呈现正常动力学。rec-1(-)菌株获得了双相曲线。噬菌体SP-10介导的转导频率在rec-1(-)和rec-2(-)菌株中与转化频率平行下降。这一结果表明，转化和SP-10转导共享一种遗传重组的共同机制。这也表明这些菌株转化频率的降低并非由于感受态的改变。相反，噬菌体PBS-1或3NT介导的转导频率在rec-1(-)菌株中并未降低。该频率在rec-2(-)菌株中降低，但不如转化或SP-10转导那样严重降低。提出了几种解释这些差异的假说。rec-1(-)突变的存在使连锁标记之间的转化重组频率降低了50%以上。rec-2(-)菌株中的连锁不受影响。rec-1(-)和rec-2(-)突变对PBS-1或3NT转导中的连锁均无影响。uvr(-)菌株以等于或高于亲本菌株的频率进行转化。这些菌株被所有噬菌体系统转导的频率比亲本菌株高约两倍。
