Exogenous Citrulline and Glutamine Contribute to Reverse the Resistance of Salmonella to Apramycin

Abstract

Antibiotic resistance is an increasing concern for human and animal health worldwide. Recently, the concept of reverting bacterial resistance by changing the metabolic state of antibiotic-resistant bacteria has emerged. In this study, we investigated the reversal of Apramycin resistance in Salmonella. First, non-targeted metabonomics were used to identify key differential metabolites of drug-resistant bacteria. Then, the reversal effect of exogenous substances was verified in vivo and in vitro. Finally, the underlying mechanism was studied. The results showed that the metabolites citrulline and glutamine were significantly reduced in Apramycin-resistant Salmonella. When citrulline and glutamine were added to the culture medium of drug-resistant Salmonella, the killing effect of Apramycin was restored markedly. Mechanistic studies showed that citrulline and glutamine promoted the Tricarboxylic acid cycle, produced more NADH in the bacteria, and increased the proton-motive force, thus promoting Apramycin entry into the bacterial cells, and killing the drug-resistant bacteria. This study provides a useful method to manage infections by antibiotic-resistant bacteria.

Exogenous D-ribose promotes gentamicin treatment of several drug-resistant Salmonella

“…Increased central carbon metabolism, especially the TCA cycle, is the core of metabolome reprogramming. Our previous work confirmed that citrulline and glutamine enhanced the apramycin-mediated killing of Salmonella via the TCA cycle (Yong et al, 2021). In the current study, D-ribose significantly increased central carbon metabolism.…”

“…Exogenous supplementation to reprogram the metabolome by repressed metabolites can alter the sensitivity of resistant strains ( Peng et al, 2015b ). Our previous study confirmed that citrulline and glutamine promoted apramycin-mediated killing ( Yong et al, 2021 ). The current study confirmed that exogenous D-ribose, which was suppressed in SCH-R, enhanced gentamicin-mediated killing in both SCH-R and SCH2021.…”

“…The membrane potential was examined using a BacLight Bacterial Membrane Potential Kit (Life Technologies, Carlsbad, CA, United Statessss) as previously described ( Yong et al, 2021 ).…”

“…Measurement of intracellular gentamicin was determined as previously described ( Yong et al, 2021 ). In brief, bacterial cells were cultured in LB broth until the late exponential phase.…”

Glutamine potentiates gentamicin to kill lab-evolved gentamicin-resistant and clinically isolated multidrug-resistant Escherichia coli

“…Metabolites-enabled killing efficacy by antibiotics is related to both antibiotic types and classes and bacterial species (Peng et al, 2015b;Zhao et al, 2021). Although glutamine potentiates antibiotic-mediated killing has been reported, only glutamine-enabled killing of E. coli by ampicillin, of Salmonella by apramycin, and of Mycobacterium persisters by rifampicin are carefully studied (Huang et al, 2018;Yong et al, 2021;Zhao et al, 2021). The present study identifies metabolites that potentiate gentamicin-mediated killing efficacy and determines glutamine-enabled killing of lab-evolved gentamicin-resistant E. coli and clinically isolated multidrug-resistant E. coli.…”