Reactive Oxygen Species-Related Ceftazidime Resistance Is Caused by the Pyruvate Cycle Perturbation and Reverted by Fe3 + in Edwardsiella tarda

Abstract

Reactive oxygen species (ROS) are related to antibiotic resistance and have been reported in bacteria. However, whether ROS contribute to ceftazidime resistance and plays a role in ceftazidime-mediated killing is unknown. The present study showed lower ROS production in ceftazidime-resistant Edwardsiella tarda (LTB4-RCAZ) than that in LTB4-sensitive E. tarda (LTB4-S), two isogenic E. tarda LTB4 strains, which was related to bacterial viability in the presence of ceftazidime. Consistently, ROS promoter Fe3+ and inhibitor thiourea elevated and reduced the ceftazidime-mediated killing, respectively. Further investigation indicated that the reduction of ROS is related to inactivation of the pyruvate cycle, which provides sources for ROS biosynthesis, but not superoxide dismutase (SOD) and catalase (CAT), which degrade ROS. Interestingly, Fe3+ promoted the P cycle, increased ROS biosynthesis, and thereby promoted ceftazidime-mediated killing. The Fe3+-induced potentiation is generalizable to cephalosporins and clinically isolated multidrug-resistant pathogens. These results show that ROS play a role in bacterial resistance and sensitivity to ceftazidime. More importantly, the present study reveals a previously unknown mechanism that Fe3+ elevates ROS production via promoting the P cycle.

Repressed Central Carbon Metabolism and Its Effect on Related Metabolic Pathways in Cefoperazone/Sulbactam-Resistant Pseudomonas aeruginosa

“…Interestingly, the major flux is from phosphoenolpyruvate to pyruvate to AcCoA, with appreciable amount of carbon going to oxalacetate from pyruvate ( Kohlstedt and Wittmann, 2019 ), which is consistent with oxaloacetate instead of AcCoA as a fuel for the P cycle ( Su et al, 2018 ). The repressed P cycle (including the TCA cycle) is related to antibiotic resistance and has been reported in some bacteria including Vibrio alginolyticus , Edwardsiella tarda , and Stenotrophomonas maltophilia ( Cheng et al, 2018 ; Gil-Gil et al, 2020 ; Li et al, 2020 ; Su et al, 2020 ; Ye et al, 2021 ). Our recent report shows that the P cycle is downregulated ( Kuang et al, 2021b ).…”

Vibrio alginolyticus Survives From Ofloxacin Stress by Metabolic Adjustment

“…It is interesting to observe that increased fatty acid biosynthesis promotes bacterial growth during antibiotic stress. The increase in fatty acid biosynthesis might be a strategy deployed by bacteria to maintain the membrane integrity as the membrane could be disrupted by antibiotic-induced ROS ( Konai and Haldar, 2017 ; Ye et al, 2021 ). The altered transcription of fatty acid biosynthesis might be attributed to the antibiotic effect that reduces the transcription and translation of lipoproteins supporting cell membrane structure ( Braun and Hantke, 2019 ).…”

Proteomic Investigation of the Antibacterial Mechanism of Cefiderocol against Escherichia coli

“…As described above, the siderophore catechol moiety on the C-3 side chain of CFDC chelated Fe 3+ into cells, and Fe 3+ was rapidly reduced to Fe 2+ by ferric reductase; thus, Fe 3+ overload promoted increased levels of Fe 2+ , and the Dps protein of E. coli could store elevated Fe 2+ with H 2 O 2 as the oxidant ( 42 , 43 ). Furthermore, the latest study reported that Fe 3+ could elevate ROS production by promoting the pyruvate cycle ( 44 ). In this study, we also identified the same results ( Fig.…”

“…Moreover, ROS stress induced by sublethal concentrations of antibiotics can lead to multidrug resistance ( 49 , 50 ). Notably, Ye et al reported that CAZ-induced ROS production was required for CAZ-mediated killing in ceftazidime-resistant Edwardsiella tarda (LTB4-R CAZ ), and a reduction in ROS production contributed to E. tarda resistance to CAZ ( 44 ). In our work, we demonstrated that CFDC confers stronger ROS stress than CPM and CAZ, and knockout of NADH-quinone oxidoreductase genes ( nuoA , nuoC , nuoE , nuoF , nuoG , nuoJ , nuoL , nuoM ) in the respiratory chain promoted insensitivity of E. coli to CFDC far beyond the effects of CPM and CAZ.…”