Acid-tolerant Pseudomonas citronellolis YN-21 exhibits a high heterotrophic nitrification capacity independent of the amo and hao genes

Yuran Yang; Xuwei Gui; Liuyi Chen; Huimiao Li; Zhenlun Li; Tuohong Liu

doi:10.1016/j.ecoenv.2024.116385

Acid-tolerant Pseudomonas citronellolis YN-21 exhibits a high heterotrophic nitrification capacity independent of the amo and hao genes

Ecotoxicol Environ Saf. 2024 May 20:279:116385. doi: 10.1016/j.ecoenv.2024.116385. Online ahead of print.

Authors

Yuran Yang¹, Xuwei Gui¹, Liuyi Chen², Huimiao Li³, Zhenlun Li⁴, Tuohong Liu¹

Affiliations

¹ Chongqing Key Laboratory of Interfacial Processes and Soil Health, College of Resources and Environment, Southwest University, Chongqing 400716, China.
² Hanhong college, southwest university, Chongqing 400716, China.
³ Chongqing Key Laboratory of Plant Disease Biology, college of Plant Protection, Southwest University, Chongqing 400716, China.
⁴ Chongqing Key Laboratory of Interfacial Processes and Soil Health, College of Resources and Environment, Southwest University, Chongqing 400716, China. Electronic address: lizhlun4740@sina.com.

PMID: 38772137
DOI: 10.1016/j.ecoenv.2024.116385

Abstract

Heterotrophic nitrifying bacteria are found to be promising candidates for implementation in wastewater treatment systems due to their tolerance to extreme environments. A novel acid-resistant bacterium, Pseudomonas citronellolis YN-21, was isolated and reported to have exceptional heterotrophic nitrification capabilities in acidic condition. At pH 5, the highest NH₄⁺ removal rate of 7.84 mg/L/h was displayed by YN-21, which was significantly higher than the NH₄⁺ removal rates of other strains in neutral and alkaline environments. Remarkably, a distinct accumulation of NH₂OH and NO₃^- was observed during NH₄⁺ removal by strain YN-21, while traditional amo and hao genes were not detected in the genome, suggesting the possible presence of alternative nitrifying genes. Moreover, excellent nitrogen removal performance was displayed by YN-21 even under high concentrations of metal ion stress. Consequently, a broad application prospect in the treatment of leather wastewater and mine tailwater is offered by YN-21.

Keywords: Ammonia oxidation; Genome; Heterotrophic aerobic nitrification; Nitrogen metabolic pathway.