Transcriptional and biochemical analyses of Planomicrobium strain AX6 from Qinghai-Tibetan Plateau, China, reveal hydrogen peroxide scavenging potential

BACKGROUND: The bacterial mechanisms responsible for hydrogen peroxide (H(2)O(2)) scavenging have been well-reported, yet little is known about how bacteria isolated from cold-environments respond to H(2)O(2) stress. Therefore, we investigated the transcriptional profiling of the Planomicrobium strain AX6 strain isolated from the cold-desert ecosystem in the Qaidam Basin, Qinghai-Tibet Plateau, China, in response to H(2)O(2) stress aiming to uncover the molecular mechanisms associated with H(2)O(2) scavenging potential. METHODS: We investigated the H(2)O(2)-scavenging potential of the bacterial Planomicrobium strain AX6 isolated from the cold-desert ecosystem in the Qaidam Basin, Qinghai-Tibet Plateau, China. Furthermore, we used high-throughput RNA-sequencing to unravel the molecular aspects associated with the H(2)O(2) scavenging potential of the Planomicrobium strain AX6 isolate. RESULTS: In total, 3,427 differentially expressed genes (DEGs) were identified in Planomicrobium strain AX6 isolate in response to 4 h of H(2)O(2) (1.5 mM) exposure. Besides, Kyoto Encyclopedia of Genes and Genomes pathway and Gene Ontology analyses revealed the down- and/or up-regulated pathways following H(2)O(2) treatment. Our study not only identified the H(2)O(2) scavenging capability of the strain nevertheless also a range of mechanisms to cope with the toxic effect of H(2)O(2) through genes involved in oxidative stress response. Compared to control, several genes coding for antioxidant proteins, including glutathione peroxidase (GSH-Px), Coproporphyrinogen III oxidase, and superoxide dismutase (SOD), were relatively up-regulated in Planomicrobium strain AX6, when exposed to H(2)O(2). CONCLUSIONS: Overall, the results suggest that the up-regulated genes responsible for antioxidant defense pathways serve as essential regulatory mechanisms for removing H(2)O(2) in Planomicrobium strain AX6. The DEGs identified here could provide a competitive advantage for the existence of Planomicrobium strain AX6 in H(2)O(2)-polluted environments. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12866-022-02677-w.