Modified beta-lactamases and uses thereof

Abstract

A tool that can screen bacteria for beta-lactamases against a panel of various antibiotics is desirable. A biosensor incorporating an indicator molecule into beta-lactamases may achieve this purpose, but it requires that the attached indicator molecule must not impair the binding affinity of the protein to a great extent to provide a higher sensitivity. A modified beta-lactamases with a residue on the ohm-loop or outside the ohm-loop but close to the active site of beta-lactamase being replaced by a reactive residue is developed in this invention. 希望有一种能针对一组不同的β-内酰胺类抗生素筛选细菌以鉴定β- 内酰胺酶的工具。一种将指示分子导入β-内酰胺酶而形成的生物传感器可达到该目的，但要求导入的指示分子基本上不会削弱蛋白质结合的亲和力，以保证较高的灵敏度。本发明研发了一种经修饰的β-内酰胺酶，该β-内酰胺酶的Ω环上或Ω环的外侧但接近其活性部位的残基被活性残基置换。