Perumbakkam Sudeep, Hess Thomas F, Crawford Ronald L
Department of Microbiology, Molecular Biology & Biochemistry, University of Idaho, Life Science 142, P.O.Box 443052, Moscow, ID, 83844-3052, USA.
Biodegradation. 2006 Dec;17(6):545-57. doi: 10.1007/s10532-005-9025-7. Epub 2006 Feb 14.
Bacterial transformation by naked DNA is thought to contribute to gene transfer and microbial evolution within natural environments. In nature many microbial communities exist as complex assemblages known as biofilms where genetic exchange is facilitated. It may be possible to take advantage of natural transformation processes to modify the phenotypes of biofilm communities giving them specific and desirable functions. Work described here shows that biofilms composed of either pure cultures or mixed populations can be transformed with specific catabolic genes such that the communities acquire the ability to degrade a particular xenobiotic compound. Biofilms were transformed by plasmids bearing genes encoding green fluorescent protein (mut2) and/or atrazine chlorohydrolase (atzA). Confocal microscopy was used to quantify the number of transformants expressing mut2 in the biofilms. Degradation of atrazine by expressed atzA was quantified by tandem mass spectrometry. PCR analysis was performed to confirm the presence of atzA in transformed biofilms. These results indicate that it should be possible to use natural transformation to enhance bioremediation processes performed by biofilms.
裸DNA介导的细菌转化被认为有助于自然环境中的基因转移和微生物进化。在自然界中，许多微生物群落以称为生物膜的复杂聚集体形式存在，在那里促进了基因交换。利用自然转化过程来改变生物膜群落的表型，赋予它们特定且理想的功能或许是可行的。此处所述的工作表明，由纯培养物或混合群体组成的生物膜可以用特定的分解代谢基因进行转化，从而使群落获得降解特定外源化合物的能力。生物膜通过携带编码绿色荧光蛋白（mut2）和/或阿特拉津氯水解酶（atzA）的基因的质粒进行转化。共聚焦显微镜用于量化生物膜中表达mut2的转化体数量。通过串联质谱法定量测定表达的atzA对阿特拉津的降解。进行PCR分析以确认转化的生物膜中存在atzA。这些结果表明，利用自然转化来增强生物膜进行的生物修复过程应该是可行的。
