Sequence of the 165-kilobase catabolic plasmid pAO1 from Arthrobacter nicotinovorans and identification of a pAO1-dependent nicotine uptake system
Sequence of the 165-kilobase catabolic plasmid pAO1 from Arthrobacter nicotinovorans and identification of a pAO1-dependent nicotine uptake system
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DOI：
10.1128/jb.185.6.1976-1986.2003
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发表时间：
2003-03-01
影响因子：
3.2
通讯作者：
Brandsch, R
中科院分区：
文献类型：
--
作者：
Igloi, GL;Brandsch, R
165-kb的分解代谢质粒pAO 1使革兰氏阳性土壤细菌节杆菌nicotinovorans上生长的烟草生物碱L-尼古丁。165，137个核苷酸的序列，总G+C含量为59.7%，除了尼古丁降解的基因和开放阅读框架（ORF）外，还揭示了一套完整的钼二核苷酸辅因子生物合成所必需的酶的ORF，以及与碳水化合物、肌氨酸和氨基酸的摄取和利用相关的ORF。在165个ORF中，约50%与代谢功能有关。pAO 1赋予A. nicotinovorans从培养基中摄取L-[C-14]尼古丁的能力，K-m为5.6 +/- 2.2 μ M。推定的尼古丁转运蛋白的ORF与D-尼古丁特异性6-羟基-D-尼古丁氧化酶的基因形成一个簇。在pAO 1上鉴定了与复制、染色体分配和自然转化功能（dprA）相关的ORF。很少有ORF显示出与已知的结合促进蛋白的相似性，但pAO 1可以通过结合转移到pAO 1阴性菌株，每个供体的转移率为10（-2）到10（-3）。没有已知功能的ORF约占pAO 1序列的35%。插入序列元件和复合转座子的位置，由pAO 1序列的G+C含量证实，表明质粒的模块组成。
The 165-kb catabolic plasmid pAO1 enables the gram-positive soil bacterium Arthrobacter nicotinovorans to grow on the tobacco alkaloid L-nicotine. The 165,137-nucleotide sequence, with an overall G+C content of 59.7%, revealed, besides genes and open reading frames (ORFs) for nicotine degradation, a complete set of ORFs for enzymes essential for the biosynthesis of the molybdenum dinucleotide cofactor, as well as ORFs related to uptake and utilization of carbohydrates, sarcosine, and amino acids. Of the 165 ORFs, approximately 50% were related to metabolic functions. pAO1 conferred to A. nicotinovorans the ability to take up L-[C-14] nicotine from the medium, with an K-m of 5.6 +/- 2.2 muM. ORFs of putative nicotine transporters formed a cluster with the gene of the D-nicotine-specific 6-hydroxy-D-nicotine oxidase. ORFs related to replication, chromosome partitioning, and natural transformation functions (dprA) were identified on pAO1. Few ORFs showed similarity to known conjugation-promoting proteins, but pAO1 could be transferred by conjugation to a pAO1-negative strain at a rate of 10(-2) to 10(-3) per donor. ORFs with no known function represented approximately 35% of the pAO1 sequence. The positions of insertion sequence elements and composite transposons, corroborated by the G+C content of the pAO1 sequence, suggest a modular composition of the plasmid.