一株耐受2,6-二叔丁基对甲酚(BHT)的副氧化微杆菌基因组学研究

Genomic Study on a Microbacterium paraoxydans Resistant to 2,6-Di-Tert-Butyl-P-Cresol (BHT)

摘要: 本研究从球等鞭金藻培养液中分离出一种藻际细菌Microbacterium_paraoxydans(副氧化微杆菌)，其对2,6-二叔丁基对甲酚(BHT)胁迫具有一定的耐受性。之后利用基因组学技术分析了副氧化微杆菌的潜在功能。结果表明：(1) 在50 mg/L BHT条件下副氧化微杆菌仍保持生长。(2) 利用基因组学技术，得到35个基因组序列GC且含量为70.38%。(3) COG注释中记录了2908个基因。其中335个碳水化合物的运输和代谢基因。KEGG注释中将副氧化微杆菌的基因功能分成6大类。其中最多的是碳水化合物代谢，注释了214个基因；生物降解和代谢注释了63个基因，包含12个通路，11个均与有机物降解有关。另外，环境信息处理通路中信号转导通路有10个，基因有76个。细胞过程中有关细菌趋化性的基因有7个。(4) KEGG注释了28种与酚类物质相关的生物降解和代谢基因，表明Microbacterium_paraoxydans具有降解和耐受有机污染物的能力，在基因角度解释了其在有机污染物BHT存在下可以生长的原因。(5) 代谢系统中预测到类胡萝卜素基因簇中包含合成类胡萝卜素的首要步骤所需要的crtB基因、idrA_B_C_D。

Abstract: This study isolated a microalgal bacterium, Microbacterium_paraoxydans, from the culture medium of Pseudomonas aeruginosa, which has a certain tolerance to 2,6-di-tert-butyl-p-cresol (BHT) stress. Subsequently, genomic techniques were used to analyze the potential functions of Microbacterium_paraoxydans. The results showed that: (1) Under the condition of 50 mg/L BHT, the growth of Microbacterium_paraoxydans was still maintained. (2) Using genomic technology, 35 genomic sequences were obtained with a GC content of 70.38%. (3) 2908 genes were recorded in the COG annotation. Among them, there are 335 genes involved in carbohydrate transport and metabolism. The KEGG annotation categorizes the gene functions of Microbacterium_paraoxydans into six major categories. The most common one is carbohydrate metabolism, with 214 genes annotated; biodegradation and metabolism annotated 63 genes, including 12 pathways, all 11 of which are related to organic matter degradation. In addition, there are 10 signal transduction pathways and 76 genes in the environmental information processing pathway. There are 7 genes related to bacterial chemotaxis in cellular processes. (4) KEGG annotated 28 biodegradation and metabolism genes related to phenolic substances, indicating that Microbacterium_paraoxydans have the ability to degrade and tolerate organic pollutants. From a genetic perspective, it explains why they can grow in the presence of organic pollutant BHT. (5) It is predicted in the metabolic system that the carotenoid gene cluster contains the crtB gene and idrA_B_C_D required for the primary step of carotenoid synthesis.