大肠杆菌蛋白可能提供新抗生素靶点

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大肠杆菌蛋白可能提供新抗生素靶点


来源：生物谷

2014年7月22日讯 /生物谷BIOON/ --最近俄亥俄州立大学的研究人员发现在大肠杆菌中的一种膜蛋白可能为新抗生素的研究提供新靶点。大肠杆菌是一种革兰氏阴性菌，其细胞膜能够阻止药物进入杀灭细菌。研究人员此次发现一种名为MurJ的膜蛋白，通过抑制这种蛋白，科学家可以有效杀灭这种最常见的革兰氏阴性菌。
研究显示，MurJ负责将一种脂质分子进行跨膜运输，一旦阻断这个过程，细菌细胞会因为渗透压不平衡而死亡。研究人员相信这一蛋白将是一个合适的抗生素靶点。这一研究目前已经被发表在权威杂志Science上。（生物谷Bioon.com）
详细英文报道：
A protein found to be essential to the survival of Escherichia coli bacteria may provide a new target for antibiotics, according to researchers from Ohio State University (OSU).
The discovery could be used to help develop new therapies to combat drug-resistant bacterial infections, a major public health problem that's lacking in research.
E. coli is a type of gram-negative bacteria, which means it has an extra membrane, called the outer membrane, that makes it more difficult for a drug to get inside the cell and kill it. E. coli cells can't survive without this critical layer. But investigators think that inhibiting a protein called MurJ would get past one of these two membranes.
Scientists from OSU found that MurJ flips a fatty molecule called a lipid from one side of a bacterial cell membrane to the other. If that molecule isn't flipped, the cell isn't able to build the necessary layer that keeps pressurized contents of the cell contained. If the contents aren't contained, the cell bursts.
"We have proof of principle that MurJ is actually a valid target because we showed that if we stop it from working, the cells will die within 10 minutes--very quickly," said Natividad Ruiz, an assistant professor of microbiology at OSU and a co-lead author of the study.
The research is published in the journal Science.
Scientists have long known most of the steps needed to create this membrane layer, which consists of sugars and amino acids cross-linked with each other. What remained unknown was which protein could get a specific lipid required for constructing this layer to change its location, from the inside of the inner membrane to the outside of that membrane.