Comparative genomics of Thermus thermophilus:: Plasticity of the megaplasmid and its contribution to a thermophilic lifestyle
Comparative genomics of Thermus thermophilus:: Plasticity of the megaplasmid and its contribution to a thermophilic lifestyle
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DOI：
10.1016/j.jbiotec.2006.03.043
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发表时间：
2006-08-05
影响因子：
4.1
通讯作者：
Chen, Chaoyin
中科院分区：
文献类型：
--
作者：
Bruggemann, Holger;Chen, Chaoyin
嗜热栖热菌在高达85摄氏度的温度下生长，并配备有生物技术感兴趣的热稳定酶。最近解码的基因组的两个菌株的嗜热T，HB27和HB8，每一个组成的染色体和一个大质粒，一定编码特定的策略，以满足嗜热菌的挑战。在这里，进行了基因组比较，以区分共同的功能，从灵活的基因库，这给了一些线索，涉及嗜热生活方式的生物学特征。染色体高度保守，约100个菌株特异性基因可能反映了相应的生物生态位的适应，如代谢特性和不同的细胞表面决定因素，包括IV型皮利。这两个巨质粒显示出较高的可塑性。在比较和重新检查它们的基因内容后，这两种巨质粒似乎都与帮助嗜热生长有关：它们的大部分基因显然参与DNA修复功能。约30质粒编码的基因表现出序列和结构域组成的相似性，预测的DNA修复系统的嗜热菌和细菌。此外，质粒编码的类胡萝卜素生物合成基因簇与参与UV诱导的DNA损伤修复的基因互锁。这说明了在升高的生长温度下DNA保护和修复的重要性。(c)2006 Elsevier B.V.保留所有权利。
The bacterium Thermus thermophilus grows at temperatures up to 85 degrees C and is equipped with thermostable enzymes of biotechnological interest. The recently decoded genomes of two strains of T thermophilus, HB27 and HB8, each composed of a chromosome and a megaplasmid, must certainly encode specific strategies to encounter the thermophile challenge. Here, a genome comparison was undertaken to distinguish common functions from the flexible gene pool, which gave some clues about the biological traits involved in a thermophile lifestyle. The chromosomes were highly conserved, with about 100 strain-specific genes probably reflecting adaptations to the corresponding biological niche, such as metabolic specialities and distinct cell surface determinates including type IV pili. The two megaplasmids showed an elevated plasticity. Upon comparison and re-examination of their gene content, both megaplasmids seem to be implicated in assisting thermophilic growth: a large portion of their genes are apparently involved in DNA repair functions. About 30 plasmid-encoded genes exhibit sequence and domain composition similarity to a predicted DNA repair system specific for thermophilic Archaea and bacteria. Moreover, the plasmid-encoded carotenoid biosynthesis gene cluster is interlocked with genes involved in UV-induced DNA damage repair. This illustrates the importance of DNA protection and repair at elevated growth temperatures. (c) 2006 Elsevier B.V. All rights reserved.