Zhao Zhenzhen, Liu Chao, Xu Qianqian, Ahmad Shahbaz, Zhang Haiyang, Pang Yu, Aikemu Abudumukeyiti, Liu Yang, Yan Hai
School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
World J Microbiol Biotechnol. 2021 Nov 5;37(12):212. doi: 10.1007/s11274-021-03181-5.
A promising bacterial strain for biodegrading dibutyl phthalate (DBP) was successfully isolated from activated sludge and characterized as a potential novel Microbacterium sp. USTB-Y based on 16S rRNA sequence analysis and whole genome average nucleotide identity (ANI). Initial DBP of 50 mg/L could be completely biodegraded by USTB-Y both in mineral salt medium and in DBP artificially contaminated soil within 12 h at the optimal culture conditions of pH 7.5 and 30 ℃, which indicates that USTB-Y has a strong ability in DBP biodegradation. Phthalic acid (PA) was identified as the end-product of DBP biodegraded by USTB-Y using GC/MS. The draft genome of USTB-Y was sequenced by Illumina NovaSeq and 29 and 188 genes encoding for putative esterase/carboxylesterase and hydrolase/alpha/beta hydrolase were annotated based on NR (non redundant protein sequence database) analysis, respectively. Gene3781 and gene3780 from strain USTB-Y showed 100% identity with dpeH and mpeH from Microbacterium sp. PAE-1. But no phthalate catabolic gene (pht) cluster was found in the genome of strain USTB-Y. The results in the present study are valuable for obtaining a more holistic understanding on diverse genetic mechanisms of PAEs biodegrading Microbacterium sp. strains.
从活性污泥中成功分离出一株有潜力的邻苯二甲酸二丁酯（DBP）降解菌，并基于16S rRNA序列分析和全基因组平均核苷酸一致性（ANI）将其鉴定为潜在的新型微杆菌属USTB-Y。在pH 7.5和30℃的最佳培养条件下，USTB-Y能够在12小时内将50mg/L的初始DBP在矿物盐培养基和DBP人工污染土壤中完全降解，这表明USTB-Y具有很强的DBP生物降解能力。利用气相色谱/质谱联用仪（GC/MS）鉴定出邻苯二甲酸（PA）是USTB-Y降解DBP的终产物。通过Illumina NovaSeq对USTB-Y的基因组草图进行测序，并基于NR（非冗余蛋白质序列数据库）分析分别注释了29个和188个编码假定酯酶/羧酸酯酶和水解酶/α/β水解酶的基因。USTB-Y菌株的Gene3781和Gene3780与微杆菌属PAE-1的dpeH和mpeH显示出100%的同一性。但在USTB-Y菌株的基因组中未发现邻苯二甲酸酯分解代谢基因（pht）簇。本研究结果对于更全面地了解PAEs降解微杆菌属菌株的多种遗传机制具有重要价值。
