Publications by authors named "Zen-Ichiro Kimura"

Autotrophic theories for the origin of metabolism posit that the first cells satisfied their carbon needs from CO and were chemolithoautotrophs that obtained their energy and electrons from H. The acetyl-CoA pathway of CO fixation is central to that view because of its antiquity: Among known CO fixing pathways it is the only one that is i) exergonic, ii) occurs in both bacteria and archaea, and iii) can be functionally replaced in full by single transition metal catalysts in vitro. In order to operate in cells at a pH close to 7, however, the acetyl-CoA pathway requires complex multi-enzyme systems capable of flavin-based electron bifurcation that reduce low potential ferredoxin-the physiological donor of electrons in the acetyl-CoA pathway-with electrons from H.

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This study introduces a groundbreaking approach for the exploration and utilization of electrotrophic acetogens, essential for advancing microbial electrosynthesis systems (MES). Our initial focus was the development of Solid-Phase Electrochemical Isolation Equipment (SPECIEs), a novel cultivation method for isolating electrotrophic acetogens directly from environmental samples on a solid medium. SPECIEs uses electrotrophy as a selection pressure, successfully overcoming the traditional cultivation method limitations and enabling the cultivation of diverse microbial communities with enhanced specificity towards acetogens.

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To isolate the useful strain for fermentation to produce bioactive compounds, we screened oligotrophic bacteria, and then strain CCS26 was isolated from leaf soil collected in Japan. This strain was capable of growth on low-nutrient medium. To elucidate the taxonomy of strain CCS26, we determined the 16S rRNA gene and draft genome sequences, respectively.

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Here, we describe the isolation and draft genome sequence of sp. CCS19. sp.

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In this study, a two-stage down-flow hanging sponge (TSDHS) reactor was used as biotrickling filter for biogas desulfurization by utilizing the anaerobic digester supernatant (ADS) of sewage sludge of an activated sludge process (ASP). The reactor comprises a closed-type first-stage down-flow hanging sponge (1st DHS) and an open-type second-stage down-flow hanging sponge (2nd DHS) reactors. In the 1st DHS, hydrogen sulfide in biogas was dissolved into the ADS, and then it was oxidized into elemental sulfur and sulfate by microbe using dissolved oxygen and nitrite in the ADS.

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Klebsiella pneumoniae subsp. CCI2 was isolated from leaf soil collected in Hiroshima Prefecture, Japan. The draft genome sequence comprises 78 contigs and contains 5,075,115 bp with a G+C content of 57.

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Current pretreatment methods for wastewater from natural rubber (NR) factories either have low rubber recovery efficiency or are costly to operate. A wastewater treatment system was developed that combines a pretreatment canal (PTC) seeded with rubber, an anaerobic baffled reactor (ABR), and a down-flow hanging sponge (DHS) reactor. The PTC is simple to implement and contributes to not only rubber recovery but also organic matter removal in the ABR and nitrogen removal in the DHS reactor.

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CCA3 was isolated from leaf soil collected in Hiroshima Prefecture, Japan. Here, we report the draft genome sequence of CCA3. The draft genome sequence of CCA3 consists of 29 contigs of 4,425,100 bp, with a GC content of 54.

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Strain CCI5, an oligotrophic bacterium, was isolated from leaf soil collected in Japan. Strain CCI5 grew at temperatures between 25 °C and 43 °C (optimum temperature, 40 °C) and at pHs between 6.0 and 10.

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Strain AS-1 was isolated from laboratory-scale activated sludge collected in Japan. This strain not only grows on rich medium, including R2A medium, but also forms colonies on medium lacking organic matter other than agar (water agar), indicating it could be used as a eurytrophic recombinant host in material production processes. Here, we present a draft genome sequence of sp.

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Strain CCI9, which was isolated from leaf soil collected in Japan, was capable of growth on poor-nutrient medium, at temperatures of 10°C to 45°C, at pHs of 4.5 to 10, and in the presence of 7.0% NaCl.

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An aerobic, oligotrophic, Gram-positive, non-sporulating, motile, rod-shaped, palladium-leaching bacterial strain, Deinococcus sp. KR-1, was previously isolated from pond water collected in Japan. This strain grew at 10 °C to 40 °C (optimum 30 °C), at pH 4.

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Strain KR-1 was isolated from pond water collected in Japan. Because this strain was capable of adsorbing palladium particles in sterilized water, strain KR-1 will be a useful biocatalyst for palladium-leaching from metal waste. Here we present a draft genome sequence of sp.

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A novel oligotrophic bacterium, designated strain CCA6, was isolated from leaf soil collected in Japan. Cells of the strain were found to be a Gram-negative, non-sporulating, motile, rod-shaped bacterium. Strain CCA6 grew at 10-45°C (optimum 20°C) and pH 4.

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An aerobic, Gram-negative, non-sporulating, motile, rod-shaped and lignin-degrading bacterial strain, Pseudomonas sp. CCA1, was isolated from leaf soil collected in Japan. This strain grew at 20-45 °C (optimum 20 °C), at pH 5.

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A1 was isolated from compost collected in Munakata City, Fukuoka Prefecture, Japan. Here, we report the first complete genome sequence of The complete genome of this strain consists of 3,488,104 bp with a GC content of 36.3% and comprises 3,362 predicted coding sequences.

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Anaerobic ammonium-oxidizing (anammox) bacteria affiliated with the genus 'Candidatus Scalindua' are responsible for significant nitrogen loss in oceans, and thus their ecophysiology is of great interest. Here, we enriched a marine anammox bacterium, 'Ca. S.

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We successfully enriched a novel anaerobic ammonium-oxidizing (anammox) bacterium affiliated with the genus 'Candidatus Brocadia' with high purity (>90%) in a membrane bioreactor (MBR). The enriched bacterium was distantly related to the hitherto characterized 'Ca. Brocadia fulgida' and 'Ca.

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Objective: A lignin-degrading bacterium, Burkholderia sp. CCA53, was previously isolated from leaf soil. The purpose of this study was to determine phenotypic and biochemical features of Burkholderia sp.

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Pseudomonas sp. strain CCA1 was isolated from leaf soil collected in Higashi-Hiroshima City in Hiroshima Prefecture, Japan. Here, we present a draft genome sequence of this strain.

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Objective: To investigate a syntrophic interaction between Geobacter sulfurreducens and hydrogenotrophic methanogens in sludge-inoculated microbial fuel cell (MFC) systems running on glucose with an improved electron recovery at the anode.

Results: The presence of archaea in MFC reduces Coulombic efficiency (CE) due to their electron scavenging capability but, here, we demonstrate that a syntrophic interaction can occur between G. sulfurreducens and hydrogenotrophic methanogens via interspecies H transfer with improvement in CE and power density.

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Burkholderia sp. strain CCA53 was isolated from leaf soil collected in Higashi-Hiroshima City in Hiroshima Prefecture, Japan. Here, we present a draft genome sequence of this strain, which consists of a total of 4 contigs containing 6,647,893 bp, with a G+C content of 67.

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Microbial degradation of lignin releases fermentable sugars, effective utilization of which could support biofuel production from lignocellulosic biomass. In the present study, a lignin-degrading bacterium was isolated from leaf soil and identified as Burkholderia sp. based on 16S rRNA gene sequencing.

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Based on the results of DNA-DNA hybridization and 16S rRNA gene sequence analyses, it was ascertained that the type strain of Moorella thermoautotrophica does not exist in any established culture collection or with the authors who originally described this species. Therefore, this species cannot be included in any further scientific studies. It is proposed that the Judicial Commission place the name Moorella thermoautotrophica on the list of rejected names if a suitable type strain is not found or a neotype is not proposed within two years following the publication of this Request for an Opinion.

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The effects of 3,5-dichlorophenol (DCP) on excess sludge reduction and microbial community dynamics were studied using laboratory-scale activated sludge reactors. The addition of 3,5-DCP at an interval of 7-8 days of operation resulted in effective reduction of growing biomass without a significant decrease in substrate removal activity. However, this uncoupling effect completely disappeared after 30 days of operation.

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