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Takasaki, Japan

Kanauchi O.,Kirin Holdings Company | Andoh A.,Shiga University of Medical Science | Mitsuyama K.,Kurume University
Journal of Agricultural and Food Chemistry | Year: 2013

The gastrointestinal tract harbors a tremendous number and variety of commensal microbiota. The intestinal mucosa simultaneously absorbs essential nutrients and protects against detrimental antigens or pathogenic microbiota as the first line of defense. Beneficial interactions between the host and microbiota are key requirements for host health. Although the gut microbiota has been previously studied in the context of inflammatory diseases, it has recently become clear that this microbial environment has a beneficial role during normal homeostasis, by modulating the immune system or bowel motor function. Recent studies revealed that microbiota, including their metabolites, modulate key signaling pathways involved in the inflammation of the mucosa or the neurotransmitter system in the gut-brain axis. The underlying molecular mechanisms of host-microbiota interactions are still unclear; however, manipulation of microbiota by probiotics or prebiotics is becoming increasingly recognized as an important therapeutic option, especially for the treatment of the dysfunction or inflammation of the intestinal tract. © 2013 American Chemical Society. Source

Harada H.,KNC Laboratories Ltd. | Misawa N.,Kirin Holdings Company | Misawa N.,Ishikawa Prefectural University
Methods in Molecular Biology | Year: 2012

Many carotenoid pigments are present in a small quantity in nature or low yielding from their natural sources, despite these vivid colorations. Thus, the synthesis of useful carotenoids with metabolic pathway-engineered microorganisms should offer an alternative and promising approach for their efficient production. Here, we describe a novel method for an efficient production of such carotenoids, using E. coli cells that carry heterologous mevalonate pathway-based genes. This method also enables relevant researchers to efficiently identify the function of an isolated carotenogenic gene candidate. For example, the recombinant E. coli cells, which harbor a lycopene-producing plasmid, can synthesize 12.5 mg/g dry cell weight of lycopene with the addition of lithium acetoacetate to the medium. This level corresponded to an 11.8-fold increase of that of E. coli cells carrying only the lycopene-producing plasmid. © 2012 Springer Science+Business Media, LLC. Source

Ohara K.,Kyoto University | Ohara K.,Kirin Holdings Company | Sasaki K.,Kyoto University | Yazaki K.,Kyoto University
Journal of Experimental Botany | Year: 2010

Long chain prenyl diphosphates are crucial biosynthetic precursors of ubiquinone (UQ) in many organisms, ranging from bacteria to humans, as well as precursors of plastoquinone in photosynthetic organisms. The cloning and characterization of two solanesyl diphosphate synthase genes, OsSPS1 and OsSPS2, in Oryza sativa is reported here. OsSPS1 was highly expressed in root tissue whereas OsSPS2 was found to be high in both leaves and roots. Enzymatic characterization using recombinant proteins showed that both OsSPS1 and OsSPS2 could produce solanesyl diphosphates as their final product, while OsSPS1 showed stronger activity than OsSPS2. However, an important biological difference was observed between the two genes: OsSPS1 complemented the yeast coq1 disruptant, which does not form UQ, whereas OsSPS2 only very weakly complemented the growth defect of the coq1 mutant. HPLC analyses showed that both OsSPS1 and OsSPS2 yeast transformants produced UQ9 instead of UQ6, which is the native yeast UQ. According to the complementation study, the UQ9 levels in OsSPS2 transformants were much lower than that of OsSPS1. Green fluorescent protein fusion analyses showed that OsSPS1 localized to mitochondria, while OsSPS2 localized to plastids. This suggests that OsSPS1 is involved in the supply of solanesyl diphosphate for ubiquinone-9 biosynthesis in mitochondria, whereas OsSPS2 is involved in providing solanesyl diphosphate for plastoquinone-9 formation. These findings indicate that O. sativa has a different mechanism for the supply of isoprenoid precursors in UQ biosynthesis from Arabidopsis thaliana, in which SPS1 provides a prenyl moiety for UQ9 at the endoplasmic reticulum. © 2010 The Author(s). Source

Ano Y.,Kirin Holdings Company | Sakudo A.,University of Ryukyus | Onodera T.,University of Tokyo
International Journal of Molecular Sciences | Year: 2012

The single-stranded RNA encephalomyocarditis virus (EMCV) can replicate in the central nervous system (CNS) and lead to prominent brain lesions in the stratum pyramidale hippocampus and the stratum granulosum cerebelli. Activated microglia cells infected by EMCV produce a massive burst of reactive oxygen species (ROS) via NADPH oxidase 2 (NOX2) activation, leading to neuronal death. Balancing this effect is mechanisms by which ROS are eliminated from the CNS. Cellular prion protein (PrP C) plays an important antioxidant role and contributes to cellular defense against EMCV infection. This review introduces recent knowledge on brain injury induced by EMCV infection via ROS generation as well as the involvement of various mediators and regulators in the pathogenesis. © 2012 by the authors; licensee MDPI, Basel, Switzerland. Source

Yu F.,Kinki University | Okamoto S.,Kinki University | Harada H.,Kirin Holdings Company | Yamasaki K.,Kinki University | And 2 more authors.
Cellular and Molecular Life Sciences | Year: 2011

Plant cytochrome P450s are involved in the biosynthesis of various classes of secondary metabolites. To elucidate the biosynthesis of zerumbone, a sesquiterpenoid with multiple potential anticancer properties, a family of P450 genes expressed in rhizomes of Zingiber zerumbet Smith, were cloned using a PCR-based cloning strategy. After functional expression in yeast, one of these P450s was found to convert α-humulene into 8-hydroxy-α-humulene, a proposed intermediate of zerumbone biosynthesis. This P450 has been designated CYP71BA1, a new member of the CYP71 family. CYP71BA1 transcripts were detected almost exclusively in rhizomes and showed a similar expression pattern to ZSS1 transcripts during rhizome development. Coexpression of a gene cluster encoding four enzymes of the mevalonate pathway with CYP71BA1 and ZSS1 in Escherichia coli leads to the production of 8-hydroxy-α-humulene in the presence of mevalonate, suggesting the possibility of microbial production of this zerumbone intermediate from a relatively simple carbon source by metabolic engineering. © 2010 Springer Basel AG. Source

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