N-NQR 通过调节 l-丙氨酸代谢赋予氨基糖苷类抗生素抗性。
Na-NQR Confers Aminoglycoside Resistance via the Regulation of l-Alanine Metabolism.
机构信息
The Third Affiliated Hospital, Sun Yat-sen University, University City, Guangzhou, People's Republic of China.
State Key Laboratory of Bio-Control, Sun Yat-sen University, University City, Guangzhou, People's Republic of China.
出版信息
mBio. 2020 Nov 17;11(6):e02086-20. doi: 10.1128/mBio.02086-20.
Sodium-translocating NADH:quinone oxidoreductase (Na-NQR) functions as a unique redox-driven sodium pump, generating membrane potential, which is related to aminoglycoside antibiotic resistance. However, whether it modulates other metabolisms to confer antibiotic resistance is unknown. The present study showed that loss of or led to differential metabolomes with elevated resistance to aminoglycoside antibiotics. Decreased alanine, aspartate, and glutamate metabolism and depressed abundance of alanine were characterized as the most impacted pathway and crucial biomarker, respectively. Further data showed that higher viability was detected in Δ and Δ mutant strains than their parent strain ATCC 33787 in the presence of gentamicin but recovered by exogenous l-alanine. It proceeds by the following events. The loss of or led to the decrease of membrane potential, ATPase activity, and then ATP and cyclic AMP (cAMP), which reduced the cAMP/CRP (cAMP receptor protein) complex. The reduced cAMP/CRP complex promoted l-alanine catabolism and inhibited l-alanine anabolism, causing reduced levels of alanine. Reduced alanine affected the expression of antiporter families Atp and Mnh genes. Our results suggest a novel mechanism by which the Na-NQR system regulates antibiotic resistance via l-alanine metabolism in a cAMP/CRP complex-dependent manner. The Na-NQR complex functions as a unique redox-driven sodium pump, generating membrane potential directly. However, whether it mediates generation of membrane potential indirectly is unknown. The present study shows that the Na-NQR complex impacts membrane potential through other antiporter families Atp and Mnh. It proceeds by ATP and then cAMP/CRP regulon, which inhibits l-alanine catabolism and promotes l-alanine anabolism. When the Na-NQR complex is reduced as in antibiotic-resistant bacteria, l-alanine is depressed, which is related to the antibiotic resistance phenotypes. However, exogenous l-alanine reverts the phenotype and promotes antibiotic-mediated killing. These findings suggest a novel mechanism by which the Na-NQR system regulates antibiotic resistance via l-alanine metabolism in a cAMP/CRP complex-dependent manner.
钠转运 NADH:醌氧化还原酶(Na-NQR)作为一种独特的氧化还原驱动的钠泵发挥作用,产生与氨基糖苷类抗生素耐药性相关的膜电位。然而,它是否调节其他代谢以赋予抗生素耐药性尚不清楚。本研究表明,缺失 或 导致对氨基糖苷类抗生素的耐药性升高的差异代谢组。特征为受影响最大的途径和关键生物标志物的分别是降低的丙氨酸、天冬氨酸和谷氨酸代谢以及降低的丙氨酸丰度。进一步的数据表明,与亲本菌株 ATCC 33787 相比,在庆大霉素存在的情况下,Δ 和 Δ 突变株的存活率更高,但通过外源性 l-丙氨酸恢复。它通过以下事件进行。缺失 或 导致膜电位、ATP 酶活性下降,进而导致 ATP 和环 AMP(环腺苷酸)下降,从而降低 cAMP/CRE(环腺苷酸受体蛋白)复合物。减少的 cAMP/CRE 复合物促进 l-丙氨酸分解代谢并抑制 l-丙氨酸合成代谢,导致丙氨酸水平降低。减少的丙氨酸影响 antiporter 家族 Atp 和 Mnh 基因的表达。我们的结果表明,Na-NQR 系统通过 cAMP/CRE 复合物依赖性方式通过 l-丙氨酸代谢调节抗生素耐药性的新机制。Na-NQR 复合体作为一种独特的氧化还原驱动的钠泵,直接产生膜电位。然而,它是否通过其他途径间接介导膜电位的产生尚不清楚。本研究表明,Na-NQR 复合体通过其他 antiporter 家族 Atp 和 Mnh 影响膜电位。它通过 ATP 然后 cAMP/CRE 调控子进行,该调控子抑制 l-丙氨酸分解代谢并促进 l-丙氨酸合成代谢。当 Na-NQR 复合体如在抗生素耐药细菌中那样减少时,l-丙氨酸被抑制,这与抗生素耐药表型有关。然而,外源性 l-丙氨酸逆转表型并促进抗生素介导的杀伤。这些发现表明,Na-NQR 系统通过 cAMP/CRE 复合物依赖性方式通过 l-丙氨酸代谢调节抗生素耐药性的新机制。