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Machida, Japan

Fujiyoshi M.,Tokai University | Yoshitake S.,Waseda University | Watanabe K.,Japan National Institute of Polar Research | Murota K.,Tokai University | And 3 more authors.
Polar Biology | Year: 2011

Polar willow (Salix polaris Wahlenb.), a mycorrhizal dwarf shrub, colonizes recently deglaciated areas in the High Arctic, Svalbard. To clarify successional changes in ECM fungi associated with S. polaris after glacier retreat, we examined the diversity and density of ECM fungi in culture and field conditions. Plant and soil samples were collected from three sites of different successional stages in the deglaciated area of Austre Brøggerbreen, near Ny-Ålesund, Svalbard. The successional stages were early stage with newly exposed bare ground (site I), transient stage with scattered colonization of Salix (sites IIa and IIb), and late stage with well-developed vegetation (site III). No ECM colonization on Salix was observed in soils collected from bare ground in early and transient stages (sites I and IIa). However, most Salix individuals showed ECM colonization in soils collected from sites close to Salix colonies in transient and late stages (sites IIb and III). Based on molecular analyses and operational taxonomic unit (OTU: >95% ITS sequence similarity) delimitations, we identified 15 OTUs/species in eight genera. The dominant OTU/species of ECM fungi identified in the transient and late stages was Geopora sp. 1 and Cenococcum sp. 1, respectively. In the culture experiment, ECM diversity was greater in late stage (eight OTUs/species) than in transient stage (three OTUs/species). This pattern was consistent with field observations, i. e., late-stage sites contained more OTUs/species of ECM fungi. These results indicate that species diversity of ECM fungi increases and the dominant species changes with the progress of succession after glacier retreat in the High Arctic. © 2010 Springer-Verlag.

Tazoe M.,Tamagawa University | Oishi H.,Tamagawa University | Kobayashi S.,HyphaGenesis Inc. | Hoshino T.,Tamagawa University
Bioscience, Biotechnology and Biochemistry | Year: 2016

4-Keto-D-arabonate synthase (4KAS), which converts 2,5-diketo-D-gluconate (DKGA) to 4-keto-Darabonate (4KA) in D-glucose oxidative fermentation by some acetic acid bacteria, was solubilized from the Gluconobacter oxydans NBRC 3292 cytoplasmic membrane, and purified in an electrophoretically homogenous state. A single membrane-bound enzyme was found to catalyze the conversion from DKGA to 4KA. The 92-kDa 4KAS was a homodimeric protein not requiring O2 or a cofactor for the conversion, but was stimulated by Mn2+ . N-terminal amino acid sequencing of 4KAS, followed by gene homology search indicated a 1,197-bp open reading frame (ORF), corresponding to the GLS-c04240 locus, GenBank accession No. CP004373, encoding a 398-amino acid protein with a calculated molecular weight of 42,818 Da. An Escherichia coli transformant with the 4kas plasmid exhibited 4KAS activity. Furthermore, overexpressed recombinant 4KAS was purified in an electrophoretically homogenous state and had the same molecular size as the natural enzyme. © 2016 Japan Society for Bioscience, Biotechnology, and Agrochemistry.

Fukuda T.,Toyama Prefectural University | Sudoh Y.,Tamagawa University | Tsuchiya Y.,Tamagawa University | Okuda T.,Tamagawa University | And 3 more authors.
Journal of Natural Products | Year: 2011

Marianins A (1) and B (2), two new prenylated phenylpropanoids, were isolated from the culture extract of the fungus Mariannaea camptospora. Structures of marianins were elucidated by interpretation of NMR and other spectroscopic data. 1 is a 5-methylcoumarin bearing two prenyloxy groups, while 2 is an orcinol derivative substituted with a 3,3-dimethyl-4-pentenoyl chain. 2 is possibly derived from 1 through a Claisen rearrangement of the prenyl group, followed by lactone hydrolysis and decarboxylation. These compounds showed weak antibacterial activity against Micrococcus luteus. (Chemical Equation Presented). © 2011 The American Chemical Society and American Society of Pharmacognosy.

Kurahashi A.,Yukiguni Maitake Co. | Kurahashi A.,HyphaGenesis Inc. | Kurahashi A.,Tokyo Kasei University | Sato M.,Yukiguni Maitake Co. | And 6 more authors.
Mycoscience | Year: 2013

We identified two aegerolysins in the transcriptome of Pleurotus eryngii that are homologs of pleurotolysin A (PlyA) and ostreolysin in P. ostreatus. The amino acid sequence of Pe.PlyA was highly homologous to that of PlyA, and Pe.ostreolysin was highly homologous to that of ostreolysin. Furthermore, these genes were both specifically and highly expressed in primordia of P. eryngii in the same manner as in P. ostreatus. The analyses revealed that Pe.PlyA and Pe.ostreolysin from P. eryngii are functional orthologues of PlyA and ostreolysin from P. ostreatus. These analyses also revealed that paralogous relationship of Pe.PlyA and Pe.ostreolysin. © 2013 The Mycological Society of Japan.

Daduang R.,Osaka University | Kitani S.,Osaka University | Sudoh Y.,HyphaGenesis Inc. | Grace Umadhay Pait I.,Osaka University | And 5 more authors.
Journal of Bioscience and Bioengineering | Year: 2015

Maklamicin is a spirotetronate-class antibiotic produced by Micromonospora sp. NBRC 110955, and a polyketide assembly line and a glycerate utilization system are involved in its biosynthesis. One tailoring step in the biosynthesis is predicted to be post-polyketide synthase (PKS) modification, which seems to be catalysed by putative cytochrome P450 monooxygenases, MakC2 and/or MakC3. In this study, we characterized makC2 and makC3 in the biosynthesis of maklamicin and identified a new maklamicin analogue from a makC2 disruptant. Gene deletion of makC2 resulted in the complete loss of maklamicin production with concomitant accumulation of a new compound (29-deoxymaklamicin), while gene deletion of makC3 did not affect the maklamicin production, indicating that 29-deoxymaklamicin is an intermediate in the biosynthetic pathway of maklamicin and should serve as the substrate of MakC2. 29-Deoxymaklamicin showed strong-to-modest anti-microbial activity against gram-positive bacteria. The fact that Streptomyces avermitilis heterologously expressing makC2 successfully converted 29-deoxymaklamicin into maklamicin confirmed that MakC2 is the final-step hydroxylase in the formation of mature maklamicin. © 2015 The Society for Biotechnology, Japan.

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