炭样小单孢菌JXNU-1产抗生素对G~-的体外抗菌作用及其机理的初步研究

基于土壤中分离到的一株具广谱抗菌活性的炭样小单孢菌JXNU-1,研究了JXNU-1所产抗生素对G-的体外抗菌作用.研究结果表明:炭样小单孢菌JXNU-1所产抗生素对产气肠杆菌、伤寒沙门氏菌、铜绿假单孢菌、福氏志贺氏菌等常见G-细菌均有抗菌作用,其最低杀菌浓度一般是最低抑菌浓度的8 ～16倍.杀菌曲线表明其对G-的杀菌作用非常快速,8h的杀菌率已超过90；.进一步的研究表明抗生素抗G-的作用机理在于抑制细菌蛋白质的合成,进而抑制细胞的分裂.

Studies on the Antimicrobial Activity and Its Mechanism of an Antibiotic,from Micromonospora carbonacea JXNU-1,Against Gram-Negative Bacteria in Vitro

Based on the strain of Micromonospora carbonacea JXNU-1 with board-spectrum antimicrobial activity,isolated from a soil sample,the antibacterial activity of its antibiotics against gram-negative bacteria in vitro was studied.The results indicated that the antibiotics had antimicrobial activity against common gram-negative bacteria,such as Enterobacter aerogenes,Salmonella typhi,Pseudomonas aeruginosa,Shigella flexneri and so on.The killing curve proved that the bactericidal action was very rapidly,the sterilizing rate over 90% when germs were treated with antibiotics for 8 hours,and the MBC usually 8 to 16 times of the MIC.Further more,studies have shown that the mechanism of the antibiotics against gram-negeative bacteria is to inhibit bacterial protein synthesis,and thereby inhibiting cell division.