著者

Takashi Okubo Takahiro Tsukui Hiroko Maita Shinobu Okamoto Kenshiro Oshima Takatomo Fujisawa Akihiro Saito Hiroyuki Futamata Reiko Hattori Yumi Shimomura Shin Haruta Sho Morimoto Yong Wang Yoriko Sakai Masahira Hattori Shin-ichi Aizawa Kenji V. P. Nagashima Sachiko Masuda Tsutomu Hattori Akifumi Yamashita Zhihua Bao Masahito Hayatsu Hiromi Kajiya-Kanegae Ikuo Yoshinaga Kazunori Sakamoto Koki Toyota Mitsuteru Nakao Mitsuyo Kohara Mizue Anda Rieko Niwa Park Jung-Hwan Reiko Sameshima-Saito Shin-ichi Tokuda Sumiko Yamamoto Syuji Yamamoto Tadashi Yokoyama Tomoko Akutsu Yasukazu Nakamura Yuka Nakahira-Yanaka Yuko Takada Hoshino Hideki Hirakawa Hisayuki Mitsui Kimihiro Terasawa Manabu Itakura Shusei Sato Wakako Ikeda-Ohtsubo Natsuko Sakakura Eli Kaminuma Kiwamu Minamisawa

出版者

Japanese Society of Microbial Ecology / Japanese Society of Soil Microbiology / Taiwan Society of Microbial Ecology / Japanese Society of Plant Microbe Interactions / Japanese Society for Extremophiles

雑誌

Microbes and Environments (ISSN:13426311)

巻号頁・発行日

pp.1203230372, (Released:2012-03-28)

参考文献数

1

被引用文献数

37 53

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Bradyrhizobium sp. S23321 is an oligotrophic bacterium isolated from paddy field soil. Although S23321 is phylogenetically close to Bradyrhizobium japonicum USDA110, a legume symbiont, it is unable to induce root nodules in siratro, a legume often used for testing Nod factor-dependent nodulation. The genome of S23321 is a single circular chromosome, 7,231,841 bp in length, with an average GC content of 64.3%. The genome contains 6,898 potential protein-encoding genes, one set of rRNA genes, and 45 tRNA genes. Comparison of the genome structure between S23321 and USDA110 showed strong colinearity; however, the symbiosis islands present in USDA110 were absent in S23321, whose genome lacked a chaperonin gene cluster (groELS3) for symbiosis regulation found in USDA110. A comparison of sequences around the tRNA-Val gene strongly suggested that S23321 contains an ancestral-type genome that precedes the acquisition of a symbiosis island by horizontal gene transfer. Although S23321 contains a nif (nitrogen fixation) gene cluster, the organization, homology, and phylogeny of the genes in this cluster were more similar to those of photosynthetic bradyrhizobia ORS278 and BTAi1 than to those on the symbiosis island of USDA110. In addition, we found genes encoding a complete photosynthetic system, many ABC transporters for amino acids and oligopeptides, two types (polar and lateral) of flagella, multiple respiratory chains, and a system for lignin monomer catabolism in the S23321 genome. These features suggest that S23321 is able to adapt to a wide range of environments, probably including low-nutrient conditions, with multiple survival strategies in soil and rhizosphere.

著者

Yuko TAKADA HOSHINO Naoyuki MATSUMOTO

出版者

Japan International Research Center for Agricultural Sciences

雑誌

Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)

巻号頁・発行日

vol.39, no.4, pp.247-252, 2005-10-31 (Released:2014-02-27)

参考文献数

29

被引用文献数

12 29

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There is an increasing interest in the extraction of DNA from soil, since molecular techniques facilitate the analysis of the microbial community including unculturable microorganisms. Though various methods of direct DNA extraction have been devised, it still remains difficult to extract DNA from some soils. We developed an improved method to extract DNA from such “recalcitrant soils”. Andisol, volcanic ash soils are recalcitrant in this context. Skim milk increased the efficacy of DNA extraction from such soils, when added to the extraction buffer as an adsorption competitor to soil particles. This method is applicable to molecular community analysis of soils which strongly adsorb DNA.