24th Pacific Science Congress (PSC-24)

Although biodegradation is crucial for the removal of triclocarban (TCC) from the contaminated environment, few microorganisms are currently known to efficiently degrade TCC, and their detoxification mechanisms remain unclear. Traditional enrichment culture methods are inefficient and prone to omission. This study employed a high-throughput strategy, integrating functional enzymes, bioinformatics databases, and extensive microbial resources to systematically analyze TCC-induced cytotoxicity and detoxification responses. From over 5,000 candidate strains, eight representative degraders were selected. Among them, Diaphorobacter polyhydroxybutyrativorans (DP) achieved a degradation rate of 26.0 ± 0.7% for 1 mg/L TCC within 48 hours and further decomposed its hydrolytic products (3,4-dichloroaniline and 4-chloroaniline). Under TCC stress, DP effectively maintained cell membrane integrity (7.72% vs. 4.50% in controls) and viability (95.22% vs. 94.89%), despite elevated levels of reactive oxygen species. Metabolic analysis revealed that TCC enhanced propanoate metabolism but suppressed the TCA cycle and electron transport chain, diverting energy from anabolism to stress response and survival. DP achieved detoxification through multiple mechanisms, including alterations in lipopolysaccharide structure, membrane permeability, efflux pumps, and enzymatic catalysis. Additionally, TCC inhibited several key energy metabolites. This study not only provides a novel approach for identifying degraders of organic pollutants but also elucidates the metabolic regulatory mechanisms by which microorganisms respond to environmental stress.
 

Triclocarban, Biodegradation, Detoxification, Functional microbe screening, Biorestoration