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

Turgut Yigit Akyol Rieko Niwa Hideki Hirakawa Hayato Maruyama Takumi Sato Takae Suzuki Ayako Fukunaga Takashi Sato Shigenobu Yoshida Keitaro Tawaraya Masanori Saito Tatsuhiro Ezawa Shusei Sato

出版者

Japanese Society of Microbial Ecology · The Japanese Society of Soil Microbiology

雑誌

Microbes and Environments (ISSN:13426311)

巻号頁・発行日

pp.ME18109, (Released:2018-12-22)

被引用文献数

31

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Arbuscular mycorrhizal (AM) fungi are important members of the root microbiome and may be used as biofertilizers for sustainable agriculture. To elucidate the impact of AM fungal inoculation on indigenous root microbial communities, we used high-throughput sequencing and an analytical pipeline providing fixed operational taxonomic units (OTUs) as an output to investigate the bacterial and fungal communities of roots treated with a commercial AM fungal inoculum in six agricultural fields. AM fungal inoculation significantly influenced the root microbial community structure in all fields. Inoculation changed the abundance of indigenous AM fungi and other fungal members in a field-dependent manner. Inoculation consistently enriched several bacterial OTUs by changing the abundance of indigenous bacteria and introducing new bacteria. Some inoculum-associated bacteria closely interacted with the introduced AM fungi, some of which belonged to the genera Burkholderia, Cellulomonas, Microbacterium, Sphingomonas, and Streptomyces and may be candidate mycorrhizospheric bacteria that contribute to the establishment and/or function of the introduced AM fungi. Inoculated AM fungi also co-occurred with several indigenous bacteria with putative beneficial traits, suggesting that inoculated AM fungi may recruit specific taxa to confer better plant performance. The bacterial families Methylobacteriaceae, Acetobacteraceae, Armatimonadaceae, and Alicyclobacillaceae were consistently reduced by the inoculation, possibly due to changes in the host plant status caused by the inoculum. To the best of our knowledge, this is the first large-scale study to investigate interactions between AM fungal inoculation and indigenous root microbial communities in agricultural fields.