Institute of Scientific Instruments of the Academy of Science of the Czech republic, v.v.i., Královopolská 147, 612 64 Brno, Czech Republic.
Molecules. 2013 Oct 24;18(11):13188-99. doi: 10.3390/molecules181113188.
Antibiotics cure infections by influencing bacterial growth or viability. Antibiotics can be divided to two groups on the basis of their effect on microbial cells through two main mechanisms, which are either bactericidal or bacteriostatic. Bactericidal antibiotics kill the bacteria and bacteriostatic antibiotics suppress the growth of bacteria (keep them in the stationary phase of growth). One of many factors to predict a favorable clinical outcome of the potential action of antimicrobial chemicals may be provided using in vitro bactericidal/bacteriostatic data (e.g., minimum inhibitory concentrations-MICs). Consequently, MICs are used in clinical situations mainly to confirm resistance, and to determine the in vitro activities of new antimicrobials. We report on the combination of data obtained from MICs with information on microorganisms' "fingerprint" (e.g., DNA/RNA, and proteins) provided by Raman spectroscopy. Thus, we could follow mechanisms of the bacteriostatic versus bactericidal action simply by detecting the Raman bands corresponding to DNA. The Raman spectra of Staphylococcus epidermidis treated with clindamycin (a bacteriostatic agent) indeed show little effect on DNA which is in contrast with the action of ciprofloxacin (a bactericidal agent), where the Raman spectra show a decrease in strength of the signal assigned to DNA, suggesting DNA fragmentation.
抗生素通过影响细菌生长或生存能力来治疗感染。抗生素可以根据其通过两种主要机制对微生物细胞的影响分为两类，即杀菌或抑菌。杀菌抗生素杀死细菌，抑菌抗生素抑制细菌的生长（使它们处于生长的静止期）。预测抗菌化学物质潜在作用的有利临床结果的许多因素之一可以通过体外杀菌/抑菌数据（例如，最小抑菌浓度-MICs）提供。因此，MIC 主要用于临床情况来确认耐药性，并确定新抗菌药物的体外活性。我们报告了从 MIC 获得的数据与拉曼光谱提供的微生物“指纹”（例如 DNA/RNA 和蛋白质）信息的组合。因此，我们可以通过检测对应于 DNA 的拉曼带来简单地跟踪抑菌与杀菌作用的机制。用克林霉素（一种抑菌剂）处理的表皮葡萄球菌的拉曼光谱确实对 DNA 几乎没有影响，这与环丙沙星（一种杀菌剂）的作用形成对比，在环丙沙星的作用下，DNA 的拉曼光谱信号强度下降，表明 DNA 碎片化。
