The study of SilE protein characteristics and its role in bacterial silver resistance

Abstract

Antimicrobial resistance is a rapidly growing epidemic that has been and continues to be responsible for significant morbidity, mortality and socioeconomic losses, worldwide. As the number of antimicrobial agents has become limited, the use of alternative agents, such as silver ions, have emerged. However, while the mechanisms of silver resistance have remained unclear, this information holds promise in reducing the future burden of antimicrobial resistance. This research is aimed to characterise the structure of SilE – a protein critically involved in silver resistance due to the presence of an operon called the Sil operon which consists of an efflux pump and a protein that binds to silver ions. Expression of SilE was mediated by the pET-28a-TEV-SilE plasmid incorporated into BL21 (DE3) Escherichia coli. The SilE protein was isolated after culture and purified using affinity. In addition, it was confirmed that the apo protein was unfolded, but there is no observation of silver induce folding as in previous studies, so the protein was not able to crystallise. Future research should aim to explore how the SilE protein can be targeted to reduce silver resistance and to augment the effect of current antimicrobials, which may help to tackle the global problem of bacterial resistance and, in turn, improve outcomes and reduce societal costs and other adversities.