Advancing biodegradation of petroleum contaminants by indigenous microbial consortia through assembly strategy innovations

Abstract

Our demand for petroleum has challenged Earth's ecosystems, causing extensive water and soil pollution. Petroleum contamination treatment technology has relied on a range of biochemical processes to treat hydrocarbon-contaminated wastes, of which microbial degradation is one of the most economical and ecological. Engineered microbial consortia can solve complex and difficult-to-degrade contaminants. However, the functional stability of consortia is challenged during long-term co-cultivation. Here, we introduced a novel strategy to design a stable consortium for degrading hydrocarbon pollutants, developed from ecological coexistence theory and trait-based method. Specifically, the degradation rate of the consortium constructed using the five strains was 31.54% higher than that of a single strain in a 6% (m/v) petroleum concentration after 16 days of co-culture. Besides, molecular characterization of the composition and transformation of petroleum-based substances further reveals the functional stability of consortium and the degradation mechanism and pattern of hydrocarbons by the consortium. Two independent soil experiments showed that the treatment of oil-contaminated soil by consortia from the indigenous microbiota maximizes the removal of hydrocarbon contaminants. Collectively, this strategy is generally applicable, facilitates the design of engineered microbial consortia, and provides a foundation for solving environmental pollution.