Dataset Information

Biodegradation and metabolic pathway of sulfamethoxazole by Sphingobacterium mizutaii.

ABSTRACT: Sulfamethoxazole (SMX) is the most commonly used antibiotic in worldwide for inhibiting aquatic animal diseases. However, the residues of SMX are difficult to eliminate and may enter the food chain, leading to considerable threats on human health. The bacterial strain Sphingobacterium mizutaii LLE5 was isolated from activated sludge. This strain could utilize SMX as its sole carbon source and degrade it efficiently. Under optimal degradation conditions (30.8 °C, pH 7.2, and inoculum amount of 3.5 × 10⁷ cfu/mL), S. mizutaii LLE5 could degrade 93.87% of 50 mg/L SMX within 7 days. Four intermediate products from the degradation of SMX were identified and a possible degradation pathway based on these findings was proposed. Furthermore, S. mizutaii LLE5 could also degrade other sulfonamides. This study is the first report on (1) degradation of SMX and other sulfonamides by S. mizutaii, (2) optimization of biodegradation conditions via response surface methodology, and (3) identification of sulfanilamide, 4-aminothiophenol, 5-amino-3-methylisoxazole, and aniline as metabolites in the degradation pathway of SMX in a microorganism. This strain might be useful for the bioremediation of SMX-contaminated environment.

SUBMITTER: Song J

PROVIDER: S-EPMC8632973 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Biodegradation and metabolic pathway of sulfamethoxazole by Sphingobacterium mizutaii.

Song Jinlong J Hao Guijie G Liu Lu L Zhang Hongyu H Zhao Dongxue D Li Xingyang X Yang Zhen Z Xu Jinhua J Ruan Zhiyong Z Mu Yingchun Y

Scientific reports 20211130 1

Sulfamethoxazole (SMX) is the most commonly used antibiotic in worldwide for inhibiting aquatic animal diseases. However, the residues of SMX are difficult to eliminate and may enter the food chain, leading to considerable threats on human health. The bacterial strain Sphingobacterium mizutaii LLE5 was isolated from activated sludge. This strain could utilize SMX as its sole carbon source and degrade it efficiently. Under optimal degradation conditions (30.8 °C, pH 7.2, and inoculum amount of 3. ...[more]

PMID: 34848765

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Dataset Information

Biodegradation and metabolic pathway of sulfamethoxazole by Sphingobacterium mizutaii.

Publications

Biodegradation and metabolic pathway of sulfamethoxazole by Sphingobacterium mizutaii.

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