Comparative genomic analysis provides insights into the evolution and niche adaptation of marine Magnetospira sp. QH‐2 strain. (10th July 2013)

• Record Type: Journal Article
• Authors: Ji, Boyang; Zhang, Sheng‐Da; Arnoux, Pascal; Rouy, Zoe; Alberto, François; Philippe, Nadège; Murat, Dorothée; Zhang, Wei‐Jia; Rioux, Jean‐Baptiste; Ginet, Nicolas; Sabaty, Monique; Mangenot, Sophie; Pradel, Nathalie; Tian, Jiesheng; Yang, Jing; Zhang, Lichen; Zhang, Wenyan; Pan, Hongmiao; Henrissat, Bernard; Coutinho, Pedro M.; Li, Ying; Xiao, Tian; Médigue, Claudine; Barbe, Valérie; Pignol, David; Talla, Emmanuel; Wu, Long‐Fei
• Is Part Of: Environmental microbiology. Volume 16:Number 2(2014:Feb.)
• Page Start: 525
• Page End: 544
• Publication Date: 2013-07-10
• Subjects: Microbial ecology -- Periodicals; Environmental Microbiology -- Periodicals; 579.17
• DOI: 10.1111/1462-2920.12180
• Languages: English
• ISSNs: 1462-2912

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>Magnetotactic bacteria (MTB) are capable of synthesizing intracellular organelles, the magnetosomes, that are membrane‐bounded magnetite or greigite crystals arranged in chains. Although MTB are widely spread in various ecosystems, few axenic cultures are available, and only freshwater <italic>Magnetospirillum</italic> spp. have been genetically analysed. Here, we present the complete genome sequence of a marine magnetotactic spirillum, <italic>Magnetospira</italic> sp. QH‐2. The high number of repeats and transposable elements account for the differences in QH‐2 genome structure compared with other relatives. Gene cluster synteny and gene correlation analyses indicate that the insertion of the magnetosome island in the QH‐2 genome occurred after divergence between freshwater and marine magnetospirilla. The presence of a sodium‐quinone reductase, sodium transporters and other functional genes are evidence of the adaptive evolution of <italic>Magnetospira</italic> sp. QH‐2 to the marine ecosystem. Genes well conserved among freshwater magnetospirilla for nitrogen fixation and assimilatory nitrate respiration are absent from the QH‐2 genome. Unlike freshwater <italic>Magnetospirillum</italic> spp., marine <italic>Magnetospira</italic> sp. QH‐2 neither has TonB and TonB‐dependent receptors nor does it grow on trace amounts of iron. Taken together, our results show a distinct, adaptive evolution of <italic>Magnetospira</italic> sp. QH‐2 to marine sediments in comparison with its closely related freshwater counterparts.</p> </abstract>