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Nitrifying microbial consortia were enriched from bark compost in a water system by regulating the amounts of organic nitrogen compounds and by controlling the aeration conditions with addition of CaCO3for maintaining suitable pH. Repeated enrichment showed reproducible mineralization of organic nitrogen via the conversion of ammonium ions () and nitrite ions () into nitrate ions (). The change in microbial composition during the enrichment was investigated by PCR-DGGE analysis with a focus on prokaryote, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, and eukaryote cell types. The microbial transition had a simple profile and showed clear relation to nitrogen ions transition.NitrosomonasandNitrobacterwere mainly detected duringandoxidation, respectively. These results revealing representative microorganisms acting in each ammonification and nitrification stages will be valuable for the development of artificial simple microbial consortia for organic hydroponics that consisted of identified heterotrophs and autotrophic nitrifying bacteria. Investigation of the transition of a nitrifying microbial community in relation to the transition of nitrogen in the organic hydroponic system. [ABSTRACT FROM PUBLISHER]

The establishment of renewable biofuel and chemical production is desirable because of global warming and the exhaustion of petroleum reserves. Sebacic acid (decanedioic acid), the material of 6,10-nylon, is produced from ricinoleic acid, a carbon-neutral material, but the process is not eco-friendly because of its energy requirements. Laccase-catalyzing oxidative cleavage of fatty acid was applied to the production of dicarboxylic acids using hydroxy and oxo fatty acids involved in the saturation metabolism of unsaturated fatty acids inLactobacillus plantarumas substrates. Hydroxy or oxo fatty acids with a functional group near the carbon–carbon double bond were cleaved at the carbon–carbon double bond, hydroxy group, or carbonyl group by laccase and transformed into dicarboxylic acids. After 8 h, 0.58 mM of sebacic acid was produced from 1.6 mM of 10-oxo-cis-12,cis-15-octadecadienoic acid (αKetoA) with a conversion rate of 35% (mol/mol). This laccase-catalyzed enzymatic process is a promising method to produce dicarboxylic acids from biomass-derived fatty acids. Oxidative cleavage of oxo unsaturated fatty acid into dicarboxylic acid by laccase. [ABSTRACT FROM PUBLISHER]

2′-O-Methylribonucleosides (2′-OMe-NRs) are promising raw materials for nucleic acid drugs because of their high thermal stability and nuclease tolerance. In the course of microbial screening for metabolic activity toward 2′-OMe-NRs,Lactobacillus buchneriLBK78 was found to decompose 2′-O-methyluridine (2′-OMe-UR). The enzyme responsible was partially purified fromL. buchneriLBK78 cells by a four-step purification procedure, and identified as a novel nucleoside hydrolase. This enzyme,LbNH, belongs to the nucleoside hydrolase superfamily, and formed a homotetrameric structure composed of subunits with a molecular mass around 34 kDa.LbNH hydrolyzed 2′-OMe-UR to 2′-O-methylribose and uracil, and the kinetic constants wereKmof 0.040 mM,kcatof 0.49 s−1, andkcat/Kmof 12 mM−1 s−1. In a substrate specificity analysis,LbNH preferred ribonucleosides and 2′-OMe-NRs as its hydrolytic substrates, but reacted weakly with 2′-deoxyribonucleosides. In a phylogenetic analysis,LbNH showed a close relationship with purine-specific nucleoside hydrolases from trypanosomes. LbNH, a novel nucleoside hydrolase fromLactobacillus buchneriLBK 78 catalyzes 1'-hydrolysis reaction toward 2'-O-methyluridine to form 2'-O-methylribose and uracil as the degradation products. [ABSTRACT FROM PUBLISHER]

The article discusses a study which examines the presence of linoleic acid isomerase in Lactobacillus-plantarum. It states that the determination of isomerization reaction was performed using a hydration step, membrane and soluble fractions. Findings of the study reveal that linoleic acid isomerase is a multi-component enzyme system which required oxidoreduction cofactors to perform its activity properly.

The article presents a study which synthesizes 4-hydroxyisoleucine (4-HIL) by aldolase-transaminase coupling reaction and basic characterization of the aldolase purified Arthrobacter simplex AKU 626. It describes the screening of an aldolase-producing bacterium. It is revealed that A. simplex AKU 626 synthesized 4-HIL from acetaldehyde, alpha-ketobutyrate and L-glutamate with Escherichia coli harboring the branched chain amino acid transaminase gene.

The article presents the study investigating the production of (R)-(S)-β-phenylalanine through stereoselective degradation for Variovorax species JH2 and Arthrobacter species. Stereoselective trans-amination was the first step in the (S)-isomer degradation while for the (R)-isomer degradation was oxidative deamination. Results of the resting cell reactions with vigorous shaking was presented.

The article presents a study which investigated 2-deoxyribose 5-phosphate production through coupling of the alcoholic fermentation system of baker's yeast and deoxyriboaldolase-expressing Escherichia coli (E. coli). Baker's yeast generates fructose 1,6-diphosphate from glucose and inorganic phosphate, and the E. coli convert the fructose 1,6-diphosphate into 2-deoxyribose 5-phosphate through D-glyceraldehyde 3-phosphate. The produced 2-deoxyribose 5-phosphate was converted to 2-deoxyribose.

The article presents a study on the bioprocessing of compounds to be used as catalyst for green chemistry in Japan. The procedure were taken in different steps, first, is the screening for biological reactions among versatile and diversity of micro-organisms. This bioprocess development were done to further discover unique metabolic processes, reactions and metabolism of microbe's enzymes.

Reports the involvement of homotropic cooperativity in indole hydroxylation catalyzed by cytochrome P450 BM-3 under alkaline conditions. Stimulant of the activity; Influence of the environment of the binding site on cooperativity; Potential of cytochrome P450 monooxygenases for environmental treatment, drug design and pharmaceutical and chemical synthesis.

Discusses the microbial production of 2-deoxyribose 5-phosphate from acetaldehyde and triosephosphate for the synthesis of 2'-deoxyribonucleosides. Amount of 2-deoxyribose 5-phosphate produced from 200 mM acetaldehyde and 117 mMdihydroxyacetone phosphate; Reactions that transformed the 2-deoxyribose 5-phosphate to 2'-deoxyribonucleoside.

Details a structural analysis of conjugated linoleic acid (CLA) produced by Lactobacillus plantarum, as well as factors affecting isomer production using proton nuclear magnetic resonance spectroscopy. Data showing that the bacterium produced two CLA isomers from linoleic acid; Addition of L-serine, glucose, silver nitrate or sodium chloride to the reaction mixture reducing production in the latter.