Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, Shaanxi, 710032, China.
Folia Microbiol (Praha). 2013 Jan;58(1):9-16. doi: 10.1007/s12223-012-0168-8. Epub 2012 Jun 9.
In consideration of high production costs of new antimicrobial drugs, a more convenient and economical method for time-kill study is urgently required. In the present experiment, we attempted to demonstrate the feasibility of microplate method as an alternative measure of macrodilution method for time-kill study. Three conventional antibiotics (ciprofloxacin, ceftazidime, and levofloxacin) and two antimicrobial peptides [A-thanatin and K(4)-S4(1-16)a] were used to determine time-kill curves against Escherichia coli ATCC 25922 and Staphylococcus epidermidis ATCC 14990. Meanwhile, both methods were also performed with three antisense peptide nucleic acids (PNA3, PNA4, and PNA5) targeting ropD gene of Staphylococcus aureus ATCC 29213 and MRSA WHO-2. In order to study the correlation between the two methods, the growth inhibition rate of PNAs, antimicrobial peptides, and antibiotics for the tested strains were evaluated. A strong agreement between the results obtained from the two methods has been demonstrated. Although microplate method required longer incubation time for a significant result than macrodilution method, the former provides a more convenient, economical, and stable way to perform time-kill test for these agents. Thus, we concluded that microplate method was an available measure for time-kill study of new antimicrobial drugs.
考虑到新抗菌药物的高生产成本，迫切需要一种更方便、更经济的时间杀伤研究方法。在本实验中，我们试图证明微孔板法作为宏观稀释法替代方法进行时间杀伤研究的可行性。使用三种常规抗生素（环丙沙星、头孢他啶和左氧氟沙星）和两种抗菌肽[Thanatin 和 K(4)-S4(1-16)a]来测定针对大肠杆菌 ATCC 25922 和表皮葡萄球菌 ATCC 14990 的时间杀伤曲线。同时，还使用三种针对金黄色葡萄球菌 ATCC 29213 和耐甲氧西林金黄色葡萄球菌（MRSA WHO-2）ropD 基因的反义肽核酸（PNA3、PNA4 和 PNA5）对这两种方法进行了测试。为了研究两种方法之间的相关性，评估了针对测试菌株的 PNAs、抗菌肽和抗生素的生长抑制率。两种方法的结果具有很强的一致性。虽然微孔板法比宏观稀释法需要更长的孵育时间才能得到显著结果，但前者提供了一种更方便、经济和稳定的方法来进行这些药物的时间杀伤试验。因此，我们得出结论，微孔板法是新抗菌药物时间杀伤研究的一种可行方法。
