著者

SHUKUO KINOSHITA SHIGEZO UDAKA MASAKAZU SHIMONO

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.3, no.3, pp.193-205, 1957 (Released:2006-08-11)

参考文献数

11

被引用文献数

78 410

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1. Screening tests for glutamate producing strains were carried out, with the media containing carbohydrate and ammonia source as chief ingredients. Glutamate as well as certain other amino acids was detected by paper chromatography in culture broth of many microorganisms tested.2. Accumulation of L-glutamate in a significant amount (at least a few mg of glutamate per ml of broth) has been demonstrated by various strains of bacteria, streptomycetes, yeasts, and fungi. The highest level of glutamate production has been obtained by a new species of Micrococcus, yielding as much as 0.25 mole of it from one mole of glucose.3. The courses of fermentations mainly by known strains of microorganisms are shown. The importances of the cultural condition and strain specificity for the production of amino acids are briefly described.

著者

Michio Matsuhashi Alla N. Pankrushina Satoshi Takeuchi Hideyuki Ohshima Housaku Miyoi Katsura Endoh Ken Murayama Hiroshi Watanabe Shigeo Endo Mikio Tobi Yoshihiro Mano Masao Hyodo Torakichi Kobayashi Tomohiko Kaneko Sugio Otani Susumu Yoshimura Akira Harata Tsuguo Sawada

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.44, no.1, pp.49-55, 1998 (Released:2005-08-24)

参考文献数

19

被引用文献数

9 56

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Bacterial cells enhance the proliferation of neighboring cells under stress conditions by emitting a physical signal. Continuous single sine sound waves produced by a speaker at frequencies of 6–10, 18–22, and 28–38 kHz promoted colony formation by Bacillus carboniphilus under non-permissive stress conditions of high KCl concentration and high temperature. Furthermore, sound waves emitted from cells of Bacillus subtilis at frequencies between 8 and 43 kHz with broad peaks at approximately 8.5, 19, 29, and 37 kHz were detected using a sensitive microphone system. The similarity between the frequency of the sound produced by B. subtilis and the frequencies that induced a response in B. carboniphilus and the previously observed growth-promoting effect of B. subtilis cells upon B. carboniphilus through iron barriers, suggest that the detected sound waves function as a growth-regulatory signal between cells.

著者

Yuko Goto Naoko Yoshida

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

pp.2016.10.001, (Released:2017-05-02)

参考文献数

31

被引用文献数

15

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Anodes are crucial in determining the electricity recovery of microbial fuel cells (MFCs). In this study, graphene oxide (GO) was used as an anodic material for electricity recovery from artificial dialysis wastewater (ADWW). Anaerobic incubation of ADWW with GO for 21 days produced a hydrogel complex containing embedded microbial cells and microbially reduced GO (rGO). The rGO complex recovered 540 to 810 μA/cm3 of catalytic current from ADWW after 10 days of electrochemical cultivation at 200 mV (vs. Ag/AgCl), which was approximately thirty times higher than that recovered from graphite felt (GF), a representative anode in MFCs. High-throughput sequencing analysis of prokaryotic 16S rRNA genes revealed a predominance of the Geobacter genus (35% of all prokaryotic sequences identified), particularly in the rGO complex after 20 days of polarization. The superior electricity recovery of the rGO complex was attributable to enhanced direct electron transfer via a well-developed biofilm, while indirect electron transfer via an electron mediator occurred in culture using GF.

著者

Courtney Cochran Hisako Masuda

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.62, no.2, pp.47-51, 2016-04-28 (Released:2016-04-27)

参考文献数

14

被引用文献数

1

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Bacillus mycoides are known to form rhizoidal colonies on solid medium. In this study, a new strain of B. mycoides, strain Ko01, was isolated from soil. Genetic and growth patterns indicated that this strain belongs to subgroup II of the B. cereus group. Strain Ko01 forms extensive rhizoidal colonies with predictable directions of rotation. The concentration of the agar, and not the chemical composition, altered the direction of the colony rotation, switching from counterclockwise to clockwise. Agar concentration-dependent switching of rotation direction was unique to strain Ko01 and was not seen in colonies of other B. mycoides strains that were tested. Factors affecting colony chirality patterns appeared to be variable among B. mycoides strains. This feature can be used for the classification of B. mycoides strains.

著者

Risha M. Patel Mary N. Heneghan Jan A. L. van Kan Andy M. Bailey Gary D. Foster

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.54, no.6, pp.367-376, 2008 (Released:2009-01-23)

参考文献数

41

被引用文献数

3 21

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This paper outlines the construction of a novel vector system comprising interchangeable terminators, as well as a multiple cloning site (MCS), to facilitate the transformation of the fungal plant pathogen Botrytis cinerea. Previous molecular studies on B. cinerea have relied upon the pLOB1 based vector system (controlled by the Aspergillus nidulans oliC promoter and a region reported to be the B. cinerea tubA terminator). Investigations, however, have revealed that, rather than the genuine B. cinerea tubA terminator, the pLOB1 terminator fragment is from another gene locus within the genome. Because previous studies have found that terminators aide in transcript stability, the main aims of this study were to develop and evaluate both vector systems, pOT (controlled by the A. nidulans oliC promoter and A. nidulans trpC terminator) and pLOB, with a range of exogenous genes, including enhanced green fluorescent protein (eGFP), monomeric red fluorescent protein (mRFP), luciferase (LUC) and β-glucuronidase (GUS). Our investigations demonstrate that pLOB and pOT based vectors are capable of expressing all four reporter genes and may be applied to future molecular studies on B. cinerea and other related ascomycetes. Additionally, this is the first reported expression of mRFP and LUC in B. cinerea.

著者

Kenta Yonezuka Jun Shimodaira Michiro Tabata Shoko Ohji Akira Hosoyama Daisuke Kasai Atsushi Yamazoe Nobuyuki Fujita Takayuki Ezaki Masao Fukuda

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

pp.2016.06.003, (Released:2016-12-17)

参考文献数

78

被引用文献数

22

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Pseudomonas putida is well-known for degradation activities for a variety of compounds and its infections have been reported. Thus, P. putida includes both clinical and nonclinical isolates. To date, no reports have examined the phylogenetic relationship between clinical and nonclinical isolates of the P. putida group. In this study, fifty-nine strains of P. putida group containing twenty-six clinical, and thirty-three nonclinical, isolates, were subjected to phylogenetic and taxonomic analyses based on 16S rRNA gene sequences and nine housekeeping gene sequences, including argS, dnaN, dnaQ, era, gltA, gyrB, ppnK, rpoB, and rpoD, to obtain insights into the diversity of species in this group. More than 97.6% similarity was observed among the 16S rRNA gene sequences of all the strains examined, indicating that the resolution of 16S rRNA gene sequences is inadequate. Phylogenetic analysis based on the individual housekeeping genes listed above improved the resolution of the phylogenetic trees, which are different from each other. Multilocus sequence analysis (MLSA) based on the concatenated sequences of the nine genes significantly improved the resolution of the phylogenetic tree, and yielded approximately the same results as average nucleotide identity (ANI) analysis, suggesting its high reliability. ANI analysis classified the fifty-nine strains into twenty-six species containing seventeen singletons and nine strain clusters based on the 95% threshold. It also indicated the mixed distribution of clinical and nonclinical isolates in the six clusters, suggesting that the genomic difference between clinical and nonclinical isolates of the P. putida group is subtle. The P. putida type strain NBRC 14164T is a singleton that is independently located from the P. putida strains distributed among the six clusters, suggesting that the classification of these strains and the differentiation of species in the P. putida group should be re-examined. This study greatly expands insights into the phylogenetic diversity of the P. putida group.

著者

TETSUO HIYAMA SHOJI MIZUSHIMA KAKUO KITAHARA

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.11, no.1, pp.51-60, 1965 (Released:2006-08-11)

参考文献数

15

被引用文献数

4 7

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As a result of quantitative studies, the racemization of lactate in Loctobacillus plantarum was found to be a cooperative reaction catalyzed by NAD-linked D- and L-lactate dehydrogenases. Any positive evidence of the existence of lactate racemase as a single enzyme in this organism could not be obtained. The former "Racemiase" is concluded to be a mixture of two enzymes.

著者

KODAMA KENKICHI KYONO TADASHI KODAMA SHOJIRO

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.8, no.1, pp.52-55, 1962

被引用文献数

5

---

A new species of yeast belonging to the Genus <i>Pichia</i> Hansen was isolated from exudation of a tree stump, (<i>Carpinus</i> spec.) in Japan. The name <i>Pichia saitoi</i> was proposed for this microorganism. A characteristic feature of this species is in its unique shape of ascospores.

著者

NORIYUKI FUKUNAGA MASATO WADA MAMORU HONJO YUHKO SETAISHI NAOKI HAYASHINAKA YASUHIRO TAKADA JIRO NISHIKAWA

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.41, no.3, pp.191-205, 1995 (Released:2006-08-22)

参考文献数

35

被引用文献数

1 10

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A Gram-negative, aerobic bacterium isolated from the bottom layer of Lake Vanda, Antarctica, can grow in a synthetic medium containing biotin as a growth factor. The lipid and fatty acid compositions of the cells grown in the fatty acid-free medium were analyzed. Phosphatidylethanolamine, phosphatidylglycerol and wax esters were identified as major components of the chloroform-methanol extractable lipids. Palmitoleic and oleic acids comprised more than 90% of the total fatty acid of the lipids when the bacterium was grown at low temperature (5°C). Increasing the growth temperature induced an increase in the average fatty acyl chain length of the phospholipids and a decrease in the unsaturation degree of the fatty acyl chain of the wax esters. Increasing the NaCl concentration in the medium also induced an increase in the average fatty acyl chain length of the phospholipids. The effects of temperature and NaCl were compared further at the level of phospholipid molecular species. The sn-2 position of phosphatidylethanolamine and the sn-1 position of phosphatidylglycerol were the most sensitive sites to changes of temperature and NaCl concentration, respectively. An aerobic desaturase system was demonstrated to be the only pathway for unsaturated fatty acid synthesis in this bacterium.

著者

Mayuko Hori Shyunsuke Oka Yoshimi Sugie Hokuto Ohtsuka Hirofumi Aiba

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.63, no.1, pp.44-50, 2017 (Released:2017-03-17)

参考文献数

28

被引用文献数

3

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Two-component signal transduction systems (TCS), that are also referred to as His to Asp phosphorelay systems, are involved in widespread cellular responses to diverse signals from bacteria to plants. Previously, we succeeded in reconstructing a cyanobacterial photo-perception system in Escherichia coli by employing a CcaS-CcaR two-component system from Nostoc punctiforme. In this study, we have added a photo-responsive ability to ArcB-ArcA (anoxic redox control) TCS of E. coli by fusing a cyanobacterial photoreceptor domain of CcaS with an intracellular histidine kinase (HK) domain of ArcB. For this, we constructed several chimeric HKs between CcaS and ArcB and found that one chimeric HK, named ArcaS9, has a photo-responsive ability. When ArcaS9 was expressed with an ArcA response regulator in E. coli expressing phycocyanobilin (PCB)-producing enzymes, the expression of sdh, a target gene of ArcB-ArcA TCS was regulated in a light-color-dependent manner. Thus we succeeded in endowing E. coli HK with a photo-responsive ability. This provides an insight into how the sensing ability of HK can be manipulated by a chimeric construct.

著者

Shingo Suzuki Akihiro Kaidow Takuma Meya Anri Masuya Takashi Shiina

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.63, no.1, pp.22-27, 2017 (Released:2017-03-17)

参考文献数

38

被引用文献数

2

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Many significant gene mutations in E. coli have contributed to the development of genetics. Among these, a commonly used recA mutation, Δ(srl–recA)306 has been sequenced by a next-generation sequencer combined with a long PCR. An original report described that Δ(srl–recA)306 cells were deleted from srlR to recA genes in their genome. The next-generation sequencer enables more accurate details to be determined. We ask whether both surrounding genes from hypF to norV for srlR and alaS for recA is there first. The long PCR was carried out with primers, norR and alaS, and amplified DNA fragments differed in length from wild to Δ(srl–recA)306 cells, suggesting that an entire Δ(srl–recA)306 mutation was included. Sequences of those DNA fragments indicated that 9147 bp, from srlR to recA including 10 genes, were replaced by a Tn10 DNA sequence. Junction points at both srlR-Tn10 and Tn10-recA were determined precisely. The results indicate that the first 97% of recA gene sequences were lost with a downstream recX gene remaining intact. The phenotypic difference between Δ(srl–recA)306 and ΔrecA::Km is discussed.

著者

Jinqiang Huang Yongjuan Li Yuzhu Luo

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

pp.2016.08.003, (Released:2017-02-24)

参考文献数

38

被引用文献数

17

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The rumen microbiome plays a vital role in ruminant nutrition and health, and its community is affected by environmental factors. However, little is known about the rumen bacterial community of ruminants living in the special ecological environment of the Qinghai-Tibetan Plateau (QTP) of China. The objectives of this study were to investigate the rumen bacterial community of the typical plateau sheep (Tibetan sheep, TS, and Gansu alpine fine-wool sheep, GS) grazing on the QTP, using 16S rRNA gene sequence analysis, and to evaluate the relationship between the rumen bacterial community and the QTP environment. A total of 116 sequences (201 clones) were examined and divided into 53 operational taxonomic units (OTUs) in the TS library and 46 OTUs in the GS library. Phylogenetic analysis showed that the sequences that belonged to the Firmicutes were the most predominant bacteria in both TS and GS libraries, representing 79.4% and 62.8% of the total clones, respectively. The remaining sequences belonged to Bacteroidetes, Proteobacteria, Actinobacteria, or were unclassified bacteria. Sequence analysis revealed that the TS and GS rumens harbored many novel sequences associated with uncultured bacteria that accounted for 63.6% and 46.8% of the total clones, respectively. Comparison of the composition and diversity of the TS and GS rumen bacteria revealed few overlapping known bacteria between the two breeds, and a higher diversity in TS. The rumen bacteria of the plateau sheep showed higher percentages of bacteria that belonged to Firmicutes and novel species compared with the low-elevation sheep. The unique bacterial community in the plateau sheep rumens is perhaps one of the major reasons that they can adapt to the harsh plateau environment. These results can help identify the rumen bacterial community of the ruminants in the QTP, and provide bacteria resources and basic data to improve ruminant productivity.

著者

Yunhong Kong James Kong Dingkang Wang Heping Huang Kaiyou Geng Yonxia Wang Yun Xia

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

pp.2016.08.002, (Released:2017-02-24)

参考文献数

37

被引用文献数

14

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In the present study, high throughput 16S rRNA gene sequencing was used to investigate soil invaded by the aggressive weed Ageratina adenophora to determine its effect on the species composition, distribution, and biodiversity of the bacterial communities. Soil samples from 12 micro-sites containing a monoculture of A. adenophora plants, mixtures of A. adenophora and different native plant species, and native species alone were studied. We found that the invasion of this weed resulted in a selection of bacteria belonging to phyla Acidobacteria and Verrucomicrobia and the lack of bacteria belonging to phyla Actinobacteria and Planctomycetes, but did not affect significantly the percentage abundances of members of other phyla. A similar bacterial population selection was also observed at genus or subgroup levels. The NO3–-N level was an important factor affecting soil bacterial communities and contributed to the dominance of A. adenophora. However, the numbers of total bacterial species, and the diversity and structure of soil bacterial microbiome did not (P > 0.05) change significantly following invasion by this weed.

著者

Ryudo Ohbayashi Hideto Akai Hirofumi Yoshikawa Wolfgang R. Hess Satoru Watanabe

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

pp.2016.02.002, (Released:2016-06-01)

参考文献数

32

被引用文献数

43

---

Cyanobacteria are photosynthetic microorganisms that serve as experimental model organisms for the study of photosynthesis, environmental stress responses, and the production of biofuels. Genetic tools for bioengineering have been developed as a result of such studies. However, there is still room for improvement for the tight control of experimental protein expression in these microorganisms. Here, we describe an expression system controlled by a theophylline-responsive riboswitch that we have constructed in the cyanobacterium Synechocystis sp. PCC 6803. We demonstrate that, in response to different theophylline concentrations, this riboswitch can tightly control green fluorescence protein expression in Synechocystis. Thus, this system is useful as a tool for genetic engineering and the synthetic biology of cyanobacteria.

著者

Akihito Endo Sanae Okada Hidetoshi Morita

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.53, no.3, pp.191-200, 2007 (Released:2007-08-29)

参考文献数

37

被引用文献数

8 31 32

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Diversity and compositions of the Lactobacillus, Streptococcus, and Bifidobacterium group in the feces of six healthy, actively racing horses (Thoroughbreds) were analyzed by using PCR-denaturing gradient gel electrophoresis (DGGE) and real-time PCR with primer sets specific for each group. PCR-DGGE analysis of the feces showed that Lactobacillus equi, Lactobacillus johnsonii, a phylogenetic relative of Lactobacillus salivarius, a phylogenetic relative of Lactobacillus gastricus, and Weissella confusa were predominant in almost all of the feces tested, and Streptococcus bovis/Streptococcus equinus was predominant in the Streptococcus group. The Bifidobacterium group was not detected by single-PCR but atypical species of the group were found in three of the six Thoroughbreds tested by nested-PCR. Calculation and estimation of lactic acid bacteria and bifidobacteria revealed that lactic acid bacteria were predominant in the feces and bifidobacteria were minor. These results indicate that the community of lactic acid bacteria and bifidobacteria in horse feces are unique because of the presence of specific species for horse feces and a minority of the Bifidobacterium group. Repeated tests of the feces from the same horse over 3 months showed that the diversity and composition of lactic acid bacteria and bifidobacteria in the feces was basically stable throughout the test period.

著者

Yoon-Jong Nam Hyun Kim Jin-Hyung Lee Hyeokjun Yoon Jong-Guk Kim

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.61, no.3, pp.67-74, 2015-06-30 (Released:2015-07-29)

参考文献数

61

被引用文献数

11

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Ulleungdo and Dokdo are volcanic islands that experience a characteristic marine climate, influenced by warm currents. The richness and diversity of the plant species, particularly vascular plants, are higher on Ulleungdo than on Dokdo. In contrast to the native plant life, little is known about the diversity of soil fungi living in the rhizosphere of these two islands. In this study, we utilized the barcoded pyrosequencing method to analyze rhizosphere soil fungi on Ulleungdo and Dokdo. In total, 768 operational taxonomic units (OTUs) were analyzed from the Ulleungdo samples, while 640 OTUs and 382 OTUs were analyzed from the Dongdo and Seodo (islets of Dokdo) samples, respectively. Species richness was considerably higher in the Ulleungdo samples than in the Dongdo and Seodo samples, while there was little difference in species diversity between the samples. The taxonomic composition analyses demonstrated that members of the phylum Basidiomycota dominated the Ulleungdo samples, whereas members of the phylum Ascomycota were predominant in the Dokdo samples. Ectomycorrhizal fungi belonging to the phylum Basidiomycota, in particular, were more abundant in the Ulleungdo samples. This finding suggests that the difference in the abundance of the ectomycorrhizal fungi in the rhizospheres of Ulleungdo and Dokdo may have been affected by species richness and diversity of the vascular plants. Our study is the first detailed report of the composition of soil fungal communities on the Ulleungdo and Dokdo islands. In addition, our findings provide a basis for understanding the ecological interactions between plants and fungi.

著者

KENKICHI KODAMA TADASHI KYONO SHOJIRO KODAMA

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.8, no.1, pp.52-55, 1962 (Released:2006-08-11)

参考文献数

4

被引用文献数

2 5

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A new species of yeast belonging to the Genus Pichia Hansen was isolated from exudation of a tree stump, (Carpinus spec.) in Japan. The name Pichia saitoi was proposed for this microorganism. A characteristic feature of this species is in its unique shape of ascospores.

著者

Edward Alain B. Pajarillo Jong-Pyo Chae Marilen P. Balolong Hyeun Bum Kim Dae-Kyung Kang

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.60, no.4, pp.140-146, 2014 (Released:2014-10-01)

参考文献数

47

被引用文献数

141

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The high level of genetic diversity in the microflora of the gastrointestinal tract has the potential to provide numerous beneficial functions to the host. Thus it is now acknowledged that the complexity in animal functioning is linked to the interacting microbiome in the gut. Despite the importance of gut microbiome, there is a lack of information concerning the microbial communities in the pig gut during the weaning transition. This study describes the fecal microbial shifts of healthy piglets during the weaning transition using barcoded pyrosequencing of the prokaryotic 16S rRNA gene. Fecal samples were obtained from 15 piglets during the pre-weaning period (fourth week after birth) and post-weaning (sixth week after birth) and were subjected to community genomic DNA extraction for pyrosequencing analysis. As the piglets underwent the weaning transition a trend toward increased bacterial diversity was observed, based on species abundance as measured by the Shannon-Weaver index. Firmicutes (54.0%) and Bacteroidetes (59.6%) were the most dominant phyla during pre-weaning and post-weaning, respectively. During the weaning transition a distinct shift from Bacteroides to Prevotella as the most abundant genus was observed. Additionally, we detected a number of abundant gut bacterial species that have not been reported previously. Clostridium rectum, C. clostridioforme, C. lactatifermentans and Butyricimonas virosa were uniquely detected prior to weaning while Roseburia cecicola and Blautia wexlerae were detected during the post-weaning period only.

著者

Ye-Eun Kim Hyeokjun Yoon Miae Kim Yoon-Jong Nam Hyun Kim Yeonggyo Seo Gyeong-Min Lee Young Ja Kim Won-Sik Kong Jong-Guk Kim Young-Bae Seu

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.60, no.2, pp.65-74, 2014 (Released:2014-05-22)

参考文献数

47

被引用文献数

14

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Dokdo, located east of the mainland of South Korea, is a volcanic island designated as a natural monument of South Korea due to its ecological value. Dokdo is divided into Dongdo and Seodo, islands with geological differences. The soil bacterial communities on Dokdo (Dongdo and Seodo) were analyzed using the pyrosequencing method. There were 1,693 and 1,408 operational taxonomic units (OTU) from Dongdo and Seodo, respectively. The statistical analyses (rarefaction curves as well as Chao1, Shannon, and Simpson indices) showed that bacterial diversity was slightly higher in Dongdo than Seodo. From results of a BLASTN search against the EzTaxon-e database, the validated reads (obtained after sequence preprocessing) were almost all classified at the phylum level. From the phylum level down to the species level, the number of classified reads considerably decreased due to the absence of information concerning unculturable or unidentified bacteria to date. Among the 36 phyla identified, three phyla (Proteobacteria, Actinobacteria and Acidobacteria) accounted for around 74.64%. The taxonomic composition was similar at the higher ranks (family and above) between Dongdo and Seodo, but a little different at the genus level. There were also various differences in the relative abundance of taxonomic ranks between Dongdo and Seodo. In particular, the proportion of the genus Acidobacterium (of the phylum Acidobacteria) was about six times higher in Seodo than Dongdo. In addition, the percentage of the genus Mycobacterium (of the phylum Actinobacteria) was nearly three times higher in Seodo than Dongdo, and the proportion of the genus Gaiella was about 3.7 times higher in Dongdo than Seodo. Overall, through the metagenomic analysis, the number of species identified in Dongdo and Seodo was 1,239 and 1,055, respectively. This information on the numerous culturable and unculturable bacteria is expected to help in the screening of new species in Dokdo.

著者

Samson Viulu Kohei Nakamura Akihiro Kojima Yuki Yoshiyasu Sakiko Saitou Kazuhiro Takamizawa

出版者

公益財団法人 応用微生物学・分子細胞生物学研究奨励会

雑誌

The Journal of General and Applied Microbiology (ISSN:00221260)

巻号頁・発行日

vol.59, no.5, pp.325-334, 2013 (Released:2013-11-08)

参考文献数

49

被引用文献数

21

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An ethanol-utilizing Fe(III)-reducing bacterial strain, OSK2AT, was isolated from a lotus field in Aichi, Japan. Phylogenetic analysis of the 16S rRNA gene sequences of OSK2AT and related strains placed it within Geobacter sulfurreducens PCAT. Strain OSK2AT was shown to be a Gram-negative, motile, rod-shaped bacterium, strictly anaerobic, 0.76−1.65 µm long and 0.28−0.45 μm wide. Its growth occurred at 20−40℃, pH 6.0−8.1, and it tolerated up to 1% NaCl. The G+C content of the genomic DNA was 61.2 mol% and DNA-DNA hybridization value with Geobacter sulfurreducens PCAT was 60.7%. The major respiratory quinone was MK-8. The major fatty acids were 16:1 ω7c, 16:0, 14:0, 15:0 iso, 16:1 ω5c, and 18:1 ω7c. Strain OSK2AT could utilize H2, ethanol, acetate, lactate, pyruvate, and formate as substrates with Fe(III)-citrate as electron acceptor. Amorphous Fe(III) hydroxide, Fe(III)-NTA, fumarate, malate, and elemental sulfur were utilized as electron acceptors with either acetate or ethanol as substrates. Results obtained from physiological, DNA-DNA hybridization, and chemotaxonomic tests support genotypic and phenotypic differentiation of strain OSK2AT from its closest relative. The isolate is assigned as a novel subspecies with the name Geobacter sulfurreducens subsp. ethanolicus, subsp. nov. (type strain OSK2AT=DSMZ 26126T=JCM 18752T).