Gualdi Stefano, Agnoli Kirsty, Vitale Alessandra, Higgins Steven, Eberl Leo
Department of Plant and Microbial Biology, University of Zürich, Switzerland.
Environ Microbiol. 2022 Feb;24(2):737-751. doi: 10.1111/1462-2920.15471. Epub 2021 Sep 3.
Members of the genus Burkholderia show remarkable abilities to adapt to a wide range of environmental conditions and is frequently isolated from soils contaminated with heavy metals. In this study, we used a transposon sequencing approach to identify 138 and 164 genes that provide a benefit for growth of the opportunistic pathogen Burkholderia cenocepacia H111 in the presence of silver and gold ions respectively. The data suggest that arginine metabolism and citrate biosynthesis are important for silver tolerance, while components of an ABC transporter (BCAL0307-BCAL0308) and de novo cysteine biosynthesis are required for tolerance to gold ions. We show that determinants that affect tolerance to both metal ions include the two-component systems BCAL0497/99 and BCAL2830/31 and genes that are involved in maintaining the integrity of the cell envelope, suggesting that membrane proteins represent important targets of silver and gold ions. Furthermore, we show that that the P-type ATPase CadA (BCAL0055), which confers tolerance to cadmium contributes to silver but not gold tolerance. Our results may be useful for improving the antibacterial effect of silver and gold ions to combat drug-resistant pathogens.
伯克霍尔德氏菌属的成员表现出显著的能力来适应广泛的环境条件，并且经常从受重金属污染的土壤中分离出来。在本研究中，我们使用转座子测序方法分别鉴定出138个和164个基因，这些基因在银离子和金离子存在的情况下为机会致病菌洋葱伯克霍尔德氏菌H111的生长提供了益处。数据表明，精氨酸代谢和柠檬酸生物合成对于银耐受性很重要，而ABC转运蛋白（BCAL0307 - BCAL0308）的成分和半胱氨酸的从头生物合成对于金离子耐受性是必需的。我们表明，影响对两种金属离子耐受性的决定因素包括双组分系统BCAL0497/99和BCAL2830/31以及参与维持细胞膜完整性的基因，这表明膜蛋白是银离子和金离子的重要靶点。此外，我们表明赋予镉耐受性的P型ATP酶CadA（BCAL0055）有助于银耐受性，但对金耐受性没有贡献。我们的结果可能有助于提高银离子和金离子对抗耐药病原体的抗菌效果。
