著者

Ryo Matsuzaki Yusuke Takashima Iwane Suzuki Masanobu Kawachi Hisayoshi Nozaki Seiichi Nohara Yousuke Degawa

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

vol.36, no.2, pp.ME21011, 2021 (Released:2021-06-16)

参考文献数

31

被引用文献数

1

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Chionaster nivalis is frequently detected in thawing snowpacks and glaciers. However, the taxonomic position of this species above the genus level remains unclear. We herein conducted molecular analyses of C. nivalis using the ribosomal RNA operon sequences obtained from more than 200 cells of this species isolated from a field-collected material. Our molecular phylogenetic analyses revealed that C. nivalis is a sister to Bartheletia paradoxa, which is an orphan basal lineage of Agaricomycotina. We also showed that C. nivalis sequences were contained in several previously examined meta-amplicon sequence datasets from snowpacks and glaciers in the Northern Hemisphere and Antarctica.

著者

Yusuke Takashima Mai Suyama Kohei Yamamoto Tomohiko Ri Kazuhiko Narisawa Yousuke Degawa

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

pp.MYC574, (Released:2022-06-17)

被引用文献数

1

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Myconymphaea yatsukahoi is a fungus that has only been isolated once from a forest in the Sugadaira Research Station, Nagano, Japan. Over 20 y have passed since its first discovery but since then it has not been rediscovered. Here, we re-isolated M. yatsukahoi from the type locality and another location, Tambara Moor, Gunma, Japan. Sporophores of this species were detected by direct field observation in Sugadaira and by induction from soil from Tambara. We attempted to narrow down isolation sources of this species by investigating the excrements of Lithobiomorpha and Scolopendromorpha centipedes, which are frequently found in the two locations where the species is distributed. In both locations, we found M. yatsukahoi in the excrements of Lithobiomorpha but not Scolopendromorpha. Myconymphaea yatsukahoi appears to be a coprophilous fungus and the excrements of the predators living in soil may be promising isolation sources for understanding the hidden diversity of kickxellalean fungi.

著者

Yusuke Takashima Kensuke Seto Yousuke Degawa Yong Guo Tomoyasu Nishizawa Hiroyuki Ohta Kazuhiko Narisawa

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.ME18081, (Released:2018-12-08)

被引用文献数

30

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Endofungal bacteria are widespread within the phylum Mucoromycota, and these include Burkholderiaceae-related endobacteria (BRE). However, the prevalence of BRE in Mortierellomycotinan fungi and their phylogenetic divergence remain unclear. Therefore, we examined the prevalence of BRE in diverse species of Mortierella. We surveyed 238 isolates of Mortierella spp. mainly obtained in Japan that were phylogenetically classified into 59 species. BRE were found in 53 isolates consisting of 22 species of Mortierella. Among them, 20 species of Mortierella were newly reported as the fungal hosts of BRE. BRE in a Glomeribacter-Mycoavidus clade in the family Burkholderiaceae were separated phylogenetically into three groups. These groups consisted of a group containing Mycoavidus cysteinexigens, which is known to be associated with M. elongata, and two other newly distinguishable groups. Our results demonstrated that BRE were harbored by many species of Mortierella and those that associated with isolates of Mortierella spp. were more phylogenetically divergent than previously reported.

著者

Yusuke Takashima Yousuke Degawa Tomoyasu Nishizawa Hiroyuki Ohta Kazuhiko Narisawa

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

vol.35, no.2, pp.ME19167, 2020 (Released:2020-04-15)

参考文献数

23

被引用文献数

8

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Bacterial endosymbionts inhabit diverse fungal lineages. Although the number of studies on bacteria is increasing, the mechanisms by which bacteria affect their fungal hosts remain unclear. We herein examined the homothallic isolate, Mortierella sugadairana YTM39, harboring a Burkholderiaceae-related endobacterium, which did not produce sexual spores. We successfully eliminated the bacterium from fungal isolates using ciprofloxacin treatment and asexual spore isolation for germinated asexual spores. Sexual spore formation by the fungus was restored by eliminating the bacterium from isolates. These results indicate that sexual reproduction by the fungus was inhibited by the bacterium. This is the first study on the sexual spore infertility of fungal hosts by endofungal bacteria.

著者

Yusuke Takashima Takeshi Nakayama Yousuke Degawa

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

pp.MYC540, (Released:2021-04-15)

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Fungi-algae interactions, such as lichen-forming fungi and parasitic chytrids on phytoplankton, are common in ecosystems. In contrast, interactions between filamentous fungi and soil algae that can be observed with the naked eye have been given little attention and remain unexplored. Here, we report a fungus that was associated with a visible symptom of dead algae on a soil surface in Sugadaira-kogen, Nagano, central Japan. Acremonium-like conidiophores were growing on vesicles and dead bodies of a yellow-green alga, Botrydium granulatum. The fungus was identified as Emericellopsis mirabilis based on its morphology by microscopic observation, phylogenetic analysis, and the similarity of the isolation substrate with the first description of the species. Co-culture experiments showed a filamentous cell differentiation of the alga by the fungus, but no harmful or beneficial effects on algal growth. Therefore, we speculate that E. mirabilis is a facultative parasite of B. granulatum under natural conditions.

著者

Kuninori Iwayama Yusuke Takashima Ko-ichi Ohtaki Kikutaro Endoh Yoshiko Tampo Nobumasa Hayase

出版者

Japanese Society of Pharmaceutical Health Care and Sciences

雑誌

医療薬学 (ISSN:1346342X)

巻号頁・発行日

vol.38, no.10, pp.617-627, 2012-10-10 (Released:2013-10-10)

参考文献数

37

被引用文献数

1 1

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We examined the effects of 8 macrolide antimicrobial agents, including 14-, 15- and 16-membered ring lactone and ketoride derivatives, on hemolysis induced by lysophosphatidylcholine (LPC) in human erythrocytes. LPC induced hemolysis at concentrations above the critical micelle concentration (4 µM). Vitamin E (α-tocopherol), used as a reference drug, attenuated the 50% hemolysis induced by 6 µM LPC when present at concentrations between 1 µM and 100 mM. Clarithromycin significantly attenuated LPC-induced hemolysis at a wider range of concentrations (100 nM to 1 mM), but other macrolides attenuated hemolysis only at high concentrations (100 µM and/or 1 mM). Since vitamin E tends to stabilize membranes due to its high lipophilicity, it appears that the high lipophilicity of clarithromycin is responsible for its protective action against damage induced by LPC. However, rokitamycin was not effective, although it is more lipophilic than clarithromycin, indicating that factors other than high lipophilicity are responsible for the protective effects of macrolide antimicrobial agents against LPC-induced hemolysis. Neither vitamin E nor clarithromycin attenuated hypotonic hemolysis (60 mM NaCl) at concentrations that inhibit LPC-induced hemolysis. On the other hand, both vitamin E and clarithromycin affected LPC micelle formation, suggesting that these drugs directly bind to LPC. We therefore believe that the protective effects of clarithromycin on LPC-induced hemolysis may be related physicochemically to its high lipophilicity and 14-membered ring lactone structure, which help maintain erythrocyte membrane integrity by preventing LPC micelle formation. These drugs likely do not act by a mechanism that protects against osmotic imbalance.