Visualizing microbial dechlorination processes in underground ecosystem by statistical correlation and network analysis approach.

Microbial ecosystems are typified by diverse microbial interactions and competition. Consequently, the microbial networks and metabolic dynamics of bioprocesses catalyzed by these ecosystems are highly complex, and their visualization is regarded as essential to bioengineering technology and innovation. Here we describe a means of visualizing the variants in a microbial community and their metabolic profiles.

Solid-, solution-, and gas-state NMR monitoring of ¹³C-cellulose degradation in an anaerobic microbial ecosystem.

Anaerobic digestion of biomacromolecules in various microbial ecosystems is influenced by the variations in types, qualities, and quantities of chemical components. Nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for characterizing the degradation of solids to gases in anaerobic digestion processes. Here we describe a characterization strategy using NMR spectroscopy for targeting the input solid insoluble biomass, catabolized soluble metabolites, and produced gases.

Cellulose digestion and metabolism induced biocatalytic transitions in anaerobic microbial ecosystems.

Anaerobic digestion of highly polymerized biomass by microbial communities present in diverse microbial ecosystems is an indispensable metabolic process for biogeochemical cycling in nature and for industrial activities required to maintain a sustainable society. Therefore, the evaluation of the complicated microbial metabolomics presents a significant challenge. We here describe a comprehensive strategy for characterizing the degradation of highly crystallized bacterial cellulose (BC) that is accompanied by metabolite production for identifying the responsible biocatalysts, including microorganisms and their metabolic functions.

Metabolic sequences of anaerobic fermentation on glucose-based feeding substrates based on correlation analyses of microbial and metabolite profiling.

Degradation processes in various biomasses are managed by complex metabolic dynamics created by diverse and extensive interactions and competition in microbial communities and their environments. It is important to develop visualization methods to provide a bird's-eye view when characterizing the entire sequential metabolic process in an environmental ecosystem. Here, we describe an approach for the visualization of the metabolic sequences in anaerobic fermentation ecosystems, characterizing the entire metabolic dynamics using a combination of microbial community profiles and metabolic profiles.

Phylogenetic analyses of bacterial communities developed in a cassette-electrode microbial fuel cell.

Quantitative and qualitative differences were analyzed between planktonic and anode-biofilm bacterial communities developed in a cassette-electrode microbial fuel cell treating starch, peptone, and fish extract. Quantitative analyses based on protein contents and rRNA-gene copy numbers indicated that planktonic microbes were over eight-times more abundant than anode-biofilm microbes. Clone-library analyses of PCR-amplified 16S rRNA gene fragments revealed the presence of bacteria affiliated with the phyla Bacteroidetes, Firmicutes, and Proteobacteria in these two communities.

Electricity generation from model organic wastewater in a cassette-electrode microbial fuel cell.

A new highly scalable microbial fuel cell (MFC) design, consisting of a series of cassette electrodes (CE), was examined for increasing power production from organic matter in wastewater. Each CE chamber was composed of a box-shaped flat cathode (two air cathodes on both sides) sandwiched in between two proton-exchange membranes and two graphite-felt anodes. Due to the simple design of the CE-MFC, multiple cassettes can be combined to form a single unit and inserted into a tank to treat wastewater.

Enhancement of RNA cleavage activity of 10-23 DNAzyme by covalently introduced intercalator.

By introducing an intercalator through D-threoninol to the 10-23 DNAzyme at the junction between its catalytic loop and the binding arm, the RNA cleavage activity was greatly improved.

Microbial community in methanogenic packed-bed reactor successfully operating at short hydraulic retention time.

The microbial community in a thermophilic anaerobic packed-bed reactor, which had been successfully operated to convert acetic and butyric acids to methane at a short hydraulic retention time (from 24 h to 1.9 h), was investigated. Archaea closely related to known methanogens were detected by 16S rRNA gene analyses of the effluents, together with diverse types of unidentified bacteria.

High-rate thermophilic methane fermentation on short-chain fatty acids in a down-flow anaerobic packed-bed reactor.

In order to maximize the efficiency of methane fermentation on short-chain fatty acids, growth media containing acetic acid and butyric acid as major carbon sources were supplied to a thermophilic down-flow anaerobic packed-bed reactor. The organic loading rate (OLR) to the reactor ranged from 0.2 to 169 kg-dichromate chemical oxygen demand(CODcr)/m(3)-reactor/day, corresponding to a hydraulic retention time (HRT) of between 1.

UV-A-induced expression of GroEL in the UV-A-resistant marine cyanobacterium Oscillatoria sp. NKBG 091600.

The authors have examined the response to UV-A irradiation of the UV-A-resistant marine cyanobacterium Oscillatoria sp. NKBG 091600, which produces the UV-A-absorbing compound biopterin glucoside. The expression of a 60 kDa protein was markedly induced at 500 min after UV-A irradiation.