bioRxiv Science⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.64898/2026.03.02.709024

Multi-omic landscape of Mn(II) oxidation in Achromobacter pulmonis ss21: From multicopper oxidase to metabolic support electron transfer

Yu, J.·Liu, Z.·Wang, H.
View original source ↗Export metadata ↓

Abstract

Microbially mediated Mn() oxidation plays a critical role in regulating the global Mn() cycle and represents an environmentally friendly strategy for remediation Mn() contaminated waters. This study presents the first demonstration that Achromobacter pulmonis ss21, a bacterium isolated from Baiyangdian Lake, exhibits the excellent capacity to oxidze Mn(). The Mn() oxidation efficiency of ss21 reached 98.82% and 97.05% for 200 and 400 mg/L Mn(), respectively. Transcriptome analysis revealed that direct Mn() oxidation was catalyzed by genes encoding copper resistance system multicopper oxidase (HV701_RS04390), LLM-type flavin oxidoreductase (HV701_RS19365) and quinone oxidoreductase (HV701_RS24690), which regulate extracellular electron transfer for continuous Mn() oxidation. In addition, thioredoxin (HV701_RS19360) and glutathione peroxidase (HV701_RS19445) genes maintained intracellular redox homeostasis, ensuring stable and efficient direct Mn() oxidation under high Mn() stress. Moreover, genes (iscU, hscA, fliS, HV701_RS03300, and HV701_RS06395) associated with metabolic support, motility, and transcriptional regulation supported indirect Mn() oxidation. Metabolomics analysis revealed the upregulation of L-Tyrosine, L-Isoleucine, glutamic acid, Gln-His-His, Flavin Adenine Dinucleotide (FAD), xanthine related to ss21 Mn() oxidation, which corresponded to the direct Mn() oxidation genes. This study provides a comprehensive understanding of the molecular mechanisms of biological Mn() oxidation by Achromobacter sp. and highlights its potential application in the bioremediation of Mn contaminated aquatic environments under high metal stress conditions. IMPORTANCEMicrobially mediated Mn() oxidation is a fundamental process in global biogeochemical cycles and offers a sustainable pathway for remediating heavy metal-polluted waters. Achromobacter pulmonis ss21 showed excellent performance in Mn() oxidation. The highly efficient removal of Mn() was achieved through oxidoreductase catalysis, regulation of extracellular electron transfer, maintenance of redox homeostasis, and ensurance of stable and efficient Mn() oxidation under high Mn() stress. Moreover, the Mn() oxidation was supported by metabolites, which prevented irreversible protein damage from oxidative stress induced by high Mn() concentration, alleviating oxidative stress, and stimulating the production of ROS. These findings expand the known diversity of Mn() oxidizing bacteria and offer valuable information for the molecular mechanisms of biological Mn() oxidation.

Source connections

Explore related subjects

microbiologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Yu, J., Liu, Z., Wang, H.. 2026-03-03. Multi-omic landscape of Mn(II) oxidation in Achromobacter pulmonis ss21: From multicopper oxidase to metabolic support electron transfer. https://doi.org/10.64898/2026.03.02.709024

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

A population-scale landscape of the subgingival microbiome reveals divergent routes to periodontal dysbiosis

Periodontitis is an archetypical mucosal inflammatory disease in which microbiome dysbiosis at the tooth-epithelial interface interacts with host genetic and behavioral risk factors to drive immune-mediated tissue destruction. Although subgingival microbiome compositional shifts are thought to parallel disease severity, microbiome variation at the population-level and its relationship to periodontal clinical phenotypes and disease-modifying factors remain poorly defined. Here, we use unsupervised manifold learning to map the compositional landscape of the subgingival microbiome in 1,355 adults spanning periodontal health to severe periodontitis. We identified eight latent microbiome states organized along a branching continuum from eubiosis to dysbiosis. An intermediate microbial configuration marked ecological destabilization and bifurcation into two distinct periodontitis-associated dysbiotic trajectories, distinguished by links to gingival inflammation and smoking. Although the microbiome trajectories broadly tracked periodontal destruction, a minority of individuals showed discordant microbiome-clinical phenotypes, with some individuals with periodontitis retaining otherwise eubiotic microbiomes enriched for low-abundance pathobionts, while some cases of health or mild disease had highly dysbiotic communities, suggesting distinct host susceptibility. Together, these findings define a population-scale ecological landscape of the subgingival microbiome, reveal divergent trajectories to periodontal dysbiosis, and highlight heterogeneity in the relationship between microbial community structure and clinical disease expression.

microbiology↗
bioRxiv2026

The iron-binding siderophore enterobactin is required for the response of multi-drug resistant Klebsiella pneumoniae to zinc limitation

To persist during infection Klebsiella pneumoniae must overcome nutrient iron and zinc limitation imposed by the host immune system through a process called nutritional immunity. Secreted small molecule siderophores are a major virulence determinant of Klebsiella pneumoniae pathogenesis and are presumed to overcome nutritional immunity by binding iron for bacterial acquisition. In this work, we set out to identify how a multi-drug resistant K. pneumoniae grows in zinc limited environments. Using unbiased transcriptomics, proteomics, and an arrayed transposon screen, we identified that synthesis and uptake of the siderophore enterobactin is required to allow for growth in low zinc conditions. Iron-specific chelators did not replicate this phenotype and addition of supplemental iron through heme in growth media could not complement severe growth defects of enterobactin mutant K. pneumoniae experiencing zinc limitation. Finally, zinc starvation induced enterobactin production independent of the canonical zinc uptake regulator (Zur) transcription factor suggesting an unidentified regulatory mechanism by which Gram-negative pathogens may respond to zinc stress. Together, these studies expand the role of enterobactin beyond iron regulation and highlight a previously unreported link between iron and zinc homeostasis in Klebsiella pneumoniae.

microbiology↗
bioRxiv2026

A microbiota-derived protease links phage susceptibility to host epithelial responses

Bacteriophages are major ecological drivers of gut microbial ecology, yet whether bacterial mechanisms that determine phage susceptibility have consequences for the mammalian host remains poorly understood. Here, we identify dipeptidyl peptidase 11 (Dpp11a), the predominant active serine protease of the prevalent gut commensal Phocaeicola vulgatus, as an unexpected bacterial defence factor. Dpp11a protects against environmental proteases and confers resistance to bacteriophage infection. Metatranscriptomic analyses further reveal increased expression of both dpp11a and P. vulgatus-associated phage transcripts in ulcerative colitis stool samples, indicating that both components of this interaction are transcriptionally active in disease-associated human microbiomes. Using the microfluidic gut-on-a-chip co-culture model HuMiX, we show that the absence of Dpp11 is accompanied by altered epithelial tight-junction remodelling during phage-bacterial infection. Together, our findings reveal that the consequences of bacterial phage defence can extend beyond phage-bacterium interactions to the mammalian epithelium.

microbiology↗