- 著者
- Tomoki NAKATSUBO Kohei NAKAMURA Tsutomu OMATSU Michiyo SUGIYAMA Tetsuo ASAI
- 出版者
- JAPANESE SOCIETY OF VETERINARY SCIENCE
- 雑誌
- Journal of Veterinary Medical Science (ISSN:09167250)
- 巻号頁・発行日
- pp.23-0042, (Released:2023-05-02)
Environmental pollution caused by antimicrobial resistance is a global public health concern. To investigate the contribution of nutrias (Myocastor coypus) to the presence of extended-spectrum β-lactamase (ESBL)–producing Enterobacterales in the Ijira River, prevalence of ESBL–producing Enterobacterales in their feces was examined using deoxycholate-hydrogen sulfide-lactose agar containing cefotaxime. Additionally, the composition of the fecal microbiota of nutria was examined using DNA metabarcoding analysis of the 16S ribosomal RNA gene and compared with that of Amami rabbit, deer, fox, and raccoon dog. The absence of ESBL–producing Enterobacterales and substantially lower abundance of Enterobacterales was observed in the feces of nutrias than in those of other wild mammals. Our results suggest the low potential of antimicrobial-resistant Enterobacterales persistence and dissemination by nutria.
- 著者
- Akihiko Hiroguchi Kohei Nakamura Tomomichi Fujita
- 出版者
- Japanese Society for Plant Biotechnology
- 雑誌
- Plant Biotechnology (ISSN:13424580)
- 巻号頁・発行日
- vol.39, no.1, pp.13-17, 2022-03-25 (Released:2022-03-25)
- 参考文献数
- 34
- 被引用文献数
- 1 2
Multicellular organisms regulate cell numbers and cell fate by using asymmetric cell division (ACD) and symmetric cell division (SCD) during their development and to adapt to unfavorable environmental conditions. A stem cell self-renews and generates differentiated cells. In plants, various types of cells are produced by ACD or SCD; however, the molecular mechanisms of ACD or SCD and the cell division mode switch are largely unknown. The moss Physcomitrium (Physcomitrella) patens is a suitable model to study plant stem cells due to its simple anatomy. Here, we report the cell division mode switch induced by abscisic acid (ABA) in P. patens. ABA is synthesized in response to abiotic stresses and induces round-shape cells, called brood cells, from cylindrical protonemal cells. Although two daughter cells with distinct sizes were produced by ACD in a protonemal stem cell on ABA-free media, the sizes of two daughter cells became similar with ABA treatment. Actin microfilaments were spatially localized on the apices of apical stem cells in protonemata on ABA-free media, but the polar accumulation was lost under the condition of ABA treatment. Moreover, ABA treatment conferred an identical cell fate to the daughter cells in terms of cell division activity. Collectively, the results indicate ABA may suppress the ACD characteristics but evoke SCD in cells. We also noticed that ABA-induced brood cells not only self-renewed but regenerated protonemal cells when ABA was removed from the media, suggesting that brood cells are novel stem cells that are induced by environmental signals in P. patens.
- 著者
- Mitsuyo Hori Yusuke Kawai Koichiro Noguchi Kohei Nakamura Masaya Shimada Hitoshi Iwahashi Tomoyuki Nakagawa
- 出版者
- Japanese Society for Food Science and Technology
- 雑誌
- Food Science and Technology Research (ISSN:13446606)
- 巻号頁・発行日
- pp.FSTR-D-23-00098, (Released:2024-01-10)
From traditional Gifu ayu-narezushi, Leuconostoc, Latilactobacillus, and Enterococcus were isolated as dominant genera. Isolated strains of Leuconostoc mesenteroides showed high growth inhibition activity against Staphylococcus aureus and Escherichia coli. The isolated strain, Enterococcus lactis EC52, could produce γ-aminobutyric acid (GABA). These results indicated that Enterococcus lactis and Leuconostoc mesenteroides were lactic acid bacteria, which have GABA-producing and antimicrobial activities, respectively, in traditional Gifu ayu-narezushi.
- 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
- 19
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).