Abstract：
Phthalate esters (PAEs) are widely used as plasticizers and cause serious complex pollution problem in environment. Thus, strains with efficient ability to simultaneously degrade various PAEs are required. In this study, a newly isolated strain Rhodococcus sp. AH-ZY2 can degrade 500 mg/L Di-n-octyl phthalate completely within 16 h and other 500 mg/L PAEs almost completely within 48 h at 37 °C, 180 rpm, and 2 % (v/v) inoculum size of cultures with a OD600 of 0.8. OD600 = 0.8, 2 % (v/v). Twenty genes in its genome were annotated as potential esterase and four of them (3963, 4547, 5294 and 5359) were heterogeneously expressed and characterized. Esterase 3963 and 4547 is a type I PAEs esterase that hydrolyzes PAEs to phthalate monoesters. Esterase 5294 is a type II PAEs esterase that hydrolyzes phthalate monoesters to phthalate acid (PA). Esterase 5359 is a type III PAEs esterase that simultaneously degrades various PAEs to PA. Molecular docking results of 5359 suggested that the size and indiscriminate binding feature of spacious substrate binding pocket may contribute to its substrate versatility. AH-ZY2 is a potential strain for efficient remediation of PAEs complex pollution in environment. It is first to report an esterase that can efficiently degrade mixed various PAEs.
摘要：
邻苯二甲酸酯(PAEs)被广泛用作增塑剂,对环境造成严重的复杂污染。因此，需要具有同时降解各种PAEs的有效能力的菌株。在这项研究中,一个新分离的菌株红球菌。AH-ZY2可以在37°C下在16小时内完全降解500mg/L的邻苯二甲酸二正辛酯，在48小时内几乎完全降解其他500mg/L的PAEs，180转/分,和2%(v/v)接种量的OD600为0.8的培养物。OD600=0.8,2%(v/v)。基因组中的20个基因被注释为潜在的酯酶，其中4个（3963、4547、5294和5359）被异源表达和表征。酯酶3963和4547是I型PAEs酯酶,其将PAEs水解为邻苯二甲酸酯单酯。酯酶5294是II型PAEs酯酶,其将邻苯二甲酸单酯水解为邻苯二甲酸(PA)。酯酶5359是III型PAEs酯酶,其同时将各种PAEs降解为PA。5359的分子对接结果表明，宽敞的底物结合袋的大小和不加区别的结合特征可能有助于其底物多功能性。AH-ZY2是高效修复环境中PAEs复杂污染的潜在菌株。首先报道了一种可以有效降解混合的各种PAEs的酯酶。
