Bomberg Malin, Timonen Sari
Department of Applied Chemistry and Microbiology, Division of Microbiology, P.O. Box 56, FIN-00014 University of Helsinki, Finland.
Appl Environ Microbiol. 2009 Jan;75(2):308-15. doi: 10.1128/AEM.01739-08. Epub 2008 Oct 31.
Group 1.1c Crenarchaeota are the predominating archaeal group in acidic boreal forest soils. In this study, we show that the detection frequency of 1.1c crenarchaeotal 16S rRNA genes in the rhizospheres of the boreal forest trees increased following colonization by the ectomycorrhizal fungus Paxillus involutus. This effect was very clear in the fine roots of Pinus sylvestris, Picea abies, and Betula pendula, the most common forest trees in Finland. The nonmycorrhizal fine roots had a clearly different composition of archaeal 16S rRNA genes in comparison to the mycorrhizal fine roots. In the phylogenetic analysis, the 1.1c crenarchaeotal 16S rRNA gene sequences obtained from the fine roots formed a well-defined cluster separate from the mycorrhizal ones. Alnus glutinosa differed from the other trees by having high diversity and detection levels of Crenarchaeota both on fine roots and on mycorrhizas as well as by harboring a distinct archaeal flora. The similarity of the archaeal populations in rhizospheres of the different tree species was increased upon colonization by the ectomycorrhizal fungus. A minority of the sequences obtained from the mycorrhizas belonged to Euryarchaeota (order Halobacteriales).
第1.1c组泉古菌是酸性北方森林土壤中占主导地位的古菌类群。在本研究中，我们发现，外生菌根真菌卷缘桩菇定殖后，北方森林树木根际中1.1c组泉古菌16S rRNA基因的检测频率增加。在芬兰最常见的森林树木欧洲赤松、欧洲云杉和垂枝桦的细根中，这种效应非常明显。与菌根细根相比，非菌根细根中古菌16S rRNA基因的组成明显不同。在系统发育分析中，从细根中获得的1.1c组泉古菌16S rRNA基因序列形成了一个与菌根序列分开的明确聚类。与其他树木不同，欧洲桤木的细根和菌根上泉古菌的多样性和检测水平都很高，并且拥有独特的古菌群落。外生菌根真菌定殖后，不同树种根际中古菌种群的相似性增加。从菌根中获得的少数序列属于广古菌门（盐杆菌目）。
