粪臭素高效降解菌YKSW-6的分离、鉴定及降解特性  

Isolation,identification and characterization of a skatole-degrading bacterial strain YKSW-6

作　　者：张宗源 周留柱 岳丹丹[1] 郭文阳 潘梦诗 亓兰达 王雪妍[1] 徐宏光 陈国参[1] 张英涛 ZHANG Zongyuan;ZHOU Liuzhu;YUE Dandan;GUO Wenyang;PAN Mengshi;QI Landa;WANG Xueyan;XU Hongguang;CHEN Guocan;ZHANG Yingtao(Institute of Biology,Henan Academy of Sciences,Zhengzhou 450000,Henan,China)

机构地区：[1]河南省科学院生物研究所,河南郑州450000

出　　处：《微生物学通报》2022年第7期2486-2499,共14页Microbiology China

基　　金：河南省科学院科研开发专项(200305007,200305002);河南省重点研发与推广专项(212102110176)。

摘　　要：【背景】粪臭素是畜牧堆肥中有机污染物的主要成分,造成养殖场及周边环境恶化,粪臭素污染问题亟待解决,利用微生物降解粪臭素是一种环保节能的有效方法。【目的】分离鉴定粪臭素高效降解菌株,研究其降解特性,为粪臭素降解提供高效的菌种资源,为该菌株应用于臭味污染环境的净化提供基础。【方法】以粪臭素为唯一碳源的无机盐培养基作为培养基质,从猪粪堆肥样品中分离筛选粪臭素高效降解菌株,通过形态特征和16S rRNA基因序列分析进行分离菌株的初步鉴定,分析其生长规律及粪臭素降解特性,并利用气相色谱质谱联用(GC-MS)对菌株代谢粪臭素的产物进行分析。【结果】从样品中分离获得一株能以粪臭素为唯一碳源的细菌YKSW-6菌株,形态学和16S rRNA基因序列分析初步鉴定该菌株为戈登氏红球菌(Rhodococcus gordoniae)。接种量为10%时,该菌培养14 h对100 mg/L的粪臭素降解率达到100%。其能够利用D-山梨醇、溴-丁二酸等18种碳源,对亚碲酸钾、溴酸钾等13种化学敏感物具有抗性。菌株YKSW-6在5%接种量、温度30-42℃和pH值为6.0-9.0时对100 mg/L的粪臭素降解效率均能达到100%,菌株生长和降解粪臭素的最佳条件为:pH 7.2,温度37℃,转速180r/min。GC-MS结果表明,粪臭素在菌株的作用下C2先被氧化,转变为3-甲基羟基吲哚,随后进一步被氧化为N-(2-乙酰基苯基)甲酰胺。同时中间产物还有苯乙醛和苯乙酸。【结论】红球菌YKSW-6为目前已报道的降解粪臭素能力较强的菌株,丰富了粪臭素降解菌种的资源库,为实际环境微生物修复应用提供了理论参考。[Background]Skatole is the main component of organic pollutants in livestock compost,which can cause the deterioration of farms and surrounding environment.Therefore,skatole pollution needs to be solved urgently.[Objective]This study aims to isolate,identify and characterize an efficient skatole-degrading bacterial strain to provide an efficient strain for the degradation of skatole and lay a foundation for the application of this strain to the remediation of odor-polluted environments.[Methods]Using the minimal salt medium with skatole as the only carbon source,we isolated an efficient skatole-degrading strain from a pig manure compost sample.Strain YKSW-6 was identified based on morphological characteristics and 16S rRNA gene sequence,and its growth pattern and skatole degradation characteristics were analyzed.Gas chromatography-mass spectrometry(GC-MS)was employed to analyze the intermediates of skatole degradation.[Results]Strain YKSW-6 was identified as Rhodococcus gordoniae.When the strain was inoculated at a ratio of 10%,the degradation rate for 100 mg/L skatole reached 100%within 14 h.This strain can utilize 18 carbon sources such as D-sorbitol and bromosuccinic acid,and was resistant to 13 chemicals such as potassium tellurite and potassium bromate.YKSW-6 completely degraded skatole in the culture medium at 5%inoculum ratio,30-42℃,and pH 6.0-9.0.The strain showed the best growth and skatole degradation performance at pH 7.2,37℃and 180 r/min.The GC-MS results showed that skatole was firstly oxidized at C2 to 3-methyloxindole,and then oxidized to N-(2-acetylphenyl)formamide by strain YKSW-6.Phenylacetaldehyde and phenylacetic acid were also the intermediates during the degradation.[Conclusion]Strain YKSW-6 is a Rhodococcus strain with strong skatole-degrading ability among the reported strains,which enriches the resource of skatole-degrading strains.The results provide a theoretical basis for the development and application of this strain.

关 键 词：粪臭素 生物降解 戈登氏红球菌 代谢机理 

分 类 号：X172[环境科学与工程—环境科学]