A first newly isolated strain capable of effectively degrading 3-methylpentane: Identification, degradation characteristics and pathway analysis

Biotechnology is applicable for the treatment of volatile organic compounds emitted from petrochemical industries. However, the biodegradation of methyl alkanes is limited by low microbial activity and poor mass transfer. Herein, a novel strain capable of effectively utilizing 3-methylpentane (3MP) as the sole carbon source was firstly isolated and identified as Mycobacterium sp. SLQ-1. The strain could function well within wide ranges of pH (5.0-8.0) and temperature (30-45℃), with the maximum specific growth and biodegradation rates being 0.084 and 0.587   h -1 , respectively. The optimum function conditions (pH 6.9, temperature 36.2℃) and 3MP removal efficiencies were predicted via response surface analysis. The repeated recycling of 2-methyl silicone oil enhanced 3MP biodegradation due to microbial adsorption. Two possible 3MP biodegradation pathways were proposed based on the analysis of metabolic intermediates, genes and enzymes. Furthermore, the strain had a wide utilization spectrum toward various alkanes, olefins and aromatics, presenting great engineering application potential.