Rosenthal K S, Storm D R
J Antibiot (Tokyo). 1977 Dec;30(12):1087-92. doi: 10.7164/antibiotics.30.1087.
One of the apparent roles of the outer membrane system in gram-negative bacteria is to function as a selective permeability barrier. A number of antibiotics active against gram-positive bacteria are relatively ineffective against gram-negative bacteria presumably because of the implied barrier function of the outer membrane. This interpretation has been strengthened by studies demonstrating synergism between outer membrane perturbing agents such as EDTA or polymyxin B and specific antibiotics. In the case of polymyxin B, it is not totally clear that synergism with other antimicrobials is due to disruption of the outer membrane permeability barrier or to interactions with the inner membrane. In order to resolve this question, polymyxin B was covalently attached to agarose in order to limit interactions with the outer surface of E. coli. These studies demonstrate that immobilized polymyxin B acts synergistically with bacitracin, rifampicin, or lysozyme. It is proposed that synergistic effects exhibited by polymyxin B are due to its interaction with the outer membrane system.
革兰氏阴性菌外膜系统的一个明显作用是作为选择性通透屏障。许多对革兰氏阳性菌有活性的抗生素对革兰氏阴性菌相对无效，这可能是由于外膜的假定屏障功能。外膜扰动剂（如EDTA或多粘菌素B）与特定抗生素之间协同作用的研究强化了这一解释。就多粘菌素B而言，与其他抗菌剂的协同作用究竟是由于外膜通透屏障的破坏还是与内膜的相互作用，目前尚不完全清楚。为了解决这个问题，将多粘菌素B共价连接到琼脂糖上，以限制其与大肠杆菌外表面的相互作用。这些研究表明，固定化的多粘菌素B与杆菌肽、利福平或溶菌酶具有协同作用。有人提出，多粘菌素B表现出的协同效应是由于其与外膜系统的相互作用。
