Bourguignon G J, Levitt M, Sternglanz R
Antimicrob Agents Chemother. 1973 Oct;4(4):479-86. doi: 10.1128/AAC.4.4.479.
With three independent techniques (absorption spectrophotometry, measurement of the deoxyribonucleic acid [DNA] melting temperature, and equilibrium dialysis), no evidence has been found for the binding of nalidixic acid to purified DNA. Also, no evidence has been found to support the hypothesis that nalidixic acid is permanently modified to a new, active compound by the bacterial cell. By using an in vitro DNA replication system developed by Bonhoeffer and colleagues, soluble extracts from nalidixic acid-sensitive cells have been shown to confer nalidixic acid sensitivity on the DNA synthesis of lysates from nalidixic acid-resistant cells. The activity in the extracts is only present in sensitive cells and is nondialyzable and heat sensitive. Finally, two known nalidixic acid-resistant mutants of Escherichia coli, mapping at nal A and nal B, respectively, have been tested to determine whether either of them is a transport mutant. It has been shown that nal B(r) is a transport mutant whereas nal A(r) is not.
通过三种独立技术（吸收分光光度法、脱氧核糖核酸[DNA]解链温度测量和平衡透析），未发现萘啶酸与纯化DNA结合的证据。此外，也没有证据支持萘啶酸被细菌细胞永久修饰为一种新的活性化合物这一假说。通过使用由邦霍费尔及其同事开发的体外DNA复制系统，已证明来自萘啶酸敏感细胞的可溶性提取物能使萘啶酸抗性细胞裂解物的DNA合成对萘啶酸敏感。提取物中的活性仅存在于敏感细胞中，不可透析且对热敏感。最后，对分别定位于nal A和nal B的两种已知的大肠杆菌萘啶酸抗性突变体进行了测试，以确定它们是否为转运突变体。结果表明，nal B(r)是一种转运突变体，而nal A(r)不是。
