Data from: Sequencing of seven haloarchaeal genomes reveals patterns of genomic flux

We report the sequencing of seven genomes from two haloarchaeal genera, Haloferax and Haloarcula. Ease of cultivation and the existence of well-developed genetic and biochemical tools for several diverse haloarchaeal species make haloarchaea a model group for the study of archaeal biology. The unique physiological properties of these organisms also make them good candidates for novel enzyme discovery for biotechnological applications. Seven genomes were sequenced to ~20×coverage and assembled to an average of 50 contigs (range 5 scaffolds - 168 contigs). Comparisons of protein-coding gene compliments revealed large-scale differences in COG functional group enrichment between these genera. Analysis of genes encoding machinery for DNA metabolism reveals genera-specific expansions of the general transcription factor TATA binding protein as well as a history of extensive duplication and horizontal transfer of the proliferating cell nuclear antigen. Insights gained from this study emphasize the importance of haloarchaea for investigation of archaeal biology.

本研究报道了来自两个嗜盐古菌属（haloarchaeal genera）的7个基因组序列，涉及盐盒菌属（Haloferax）与哈氏嗜盐菌属（Haloarcula）。由于多种嗜盐古菌（haloarchaea）易于培养，且已建立成熟完善的遗传与生化研究工具，因此嗜盐古菌成为古菌生物学研究的模式类群。此外，这类微生物独特的生理特性，使其成为生物技术应用中新型酶类发掘的优质候选对象。本次测序的7个基因组均达到约20倍测序覆盖度，组装后平均得到50个重叠群（contigs），组装结果的重叠群数量范围为5个支架（scaffolds）至168个重叠群。通过对各基因组编码蛋白基因组成的比较分析，发现这两个属在COG（Clusters of Orthologous Groups）功能类群的富集程度上存在显著的大规模差异。针对编码DNA代谢相关功能系统的基因进行分析后发现，两个属在通用转录因子TATA结合蛋白（TATA binding protein）的基因组扩张上存在属特异性差异，同时增殖细胞核抗原（proliferating cell nuclear antigen, PCNA）也存在广泛的基因复制与水平转移历史。本研究获得的见解进一步凸显了嗜盐古菌在古菌生物学研究中的重要价值。