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Transcriptome analysis of the brown rot fungus \u3cem\u3eGloeophyllum trabeum\u3c/em\u3e during lignocellulose degradation
Brown rot fungi have great potential in biorefinery wood conversion systems because they are the primary wood decomposers in coniferous forests and have an efficient lignocellulose degrading system. Their initial wood degradation mechanism is thought to consist of an oxidative radical-based system that acts sequentially with an enzymatic saccharification system, but the complete molecular mechanism of this system has not yet been elucidated. Some studies have shown that wood degradation mechanisms of brown rot fungi have diversity in their substrate selectivity. Gloeophyllum trabeum, one of the most studied brown rot species, has broad substrate selectivity and even can degrade some grasses. However, the basis for this broad substrate specificity is poorly understood. In this study, we performed RNA-seq analyses on G. trabeum grown on media containing glucose, cellulose, or Japanese cedar (Cryptomeria japonica) as the sole carbon source. Comparison to the gene expression on glucose, 1,129 genes were upregulated on cellulose and 1,516 genes were upregulated on cedar. Carbohydrate Active enZyme (CAZyme) genes upregulated on cellulose and cedar media by G. trabeum included glycoside hyrolase family 12 (GH12), GH131, carbohydrate esterase family 1 (CE1), auxiliary activities family 3 subfamily 1 (AA3_1), AA3_2, AA3_4 and AA9, which is a newly reported expression pattern for brown rot fungi. The upregulation of both terpene synthase and cytochrome P450 genes on cedar media suggests the potential importance of these gene products in the production of secondary metabolites associated with the chelator-mediated Fenton reaction. These results provide new insights into the inherent wood degradation mechanism of G. trabeum and the diversity of brown rot mechanisms
validity of dietary diversity
The validity of dietary variety score (DVS) using a short-form questionnaire has not been investigated using dietary diversity based on a quantitative distribution of consumed foods in older Japanese. We examined the association between DVS and objective dietary diversity using a Quantitative Index for Dietary Diversity (QUANTIDD) based on the quantitative distribution of foods consumed by older Japanese community dwellers. The subjects were 65 older Japanese community dwellers aged 60–79 years. We used two kinds of scores for assessment of dietary diversity. At first, dietary diversity was determined using DVS calculated from answers to a questionnaire about frequencies of intake of 10 food groups. Second, dietary intake was assessed using a 3-day dietary record with photographs, and dietary diversity was determined using QUANTIDD. The relationships between DVS and QUANTIDD were assessed using partial correlation coefficients controlling for confounders. The correlation coefficient between DVS and QUANTIDD was moderate (r = 0.212-0.458). After controlling for confounders, those correlation coefficient between DVS and QUANTIDD remained moderate. The findings suggest that there was a moderate relationship between DVS and QUANTIDD, and DVS using a short-form questionnaire may be useful for assessing dietary diversity in older Japanese community dwellers
Evaluation of privacy in high dynamic range video sequences
The ability of high dynamic range (HDR) to capture details in environments with high contrast has a significant impact on privacy in video surveillance. However, the extent to which HDR imaging affects privacy, when compared to a typical low dynamic range (LDR) imaging, is neither well studied nor well understood. To achieve such an objective, a suitable dataset of images and video sequences is needed. Therefore, we have created a publicly available dataset of HDR video for privacy evaluation PEViD-HDR, which is an HDR extension of an existing Privacy Evaluation Video Dataset (PEViD). PEViD-HDR video dataset can help in the evaluations of privacy protection tools, as well as for showing the importance of HDR imaging in video surveillance applications and its influence on the privacy-intelligibility trade-off. We conducted a preliminary subjective experiment demonstrating the usability of the created dataset for evaluation of privacy issues in video. The results confirm that a tone-mapped HDR video contains more privacy sensitive information and details compared to a typical LDR video
Overproduction of the membrane-bound [NiFe]-hydrogenase in Thermococcus kodakarensis and its effect on hydrogen production
The hyperthermophilic archaeon Thermococcus kodakarensis can utilize sugars or pyruvate for growth. In the absence of elemental sulfur, the electrons via oxidation of these substrates are accepted by protons, generating molecular hydrogen (H2). The hydrogenase responsible for this reaction is a membrane-bound [NiFe]-hydrogenase (Mbh). In this study, we have examined several possibilities to increase the protein levels of Mbh in T. kodakarensis by genetic engineering. Highest levels of intracellular Mbh levels were achieved when the promoter of the entire mbh operon (TK2080-TK2093) was exchanged to a strong constitutive promoter from the glutamate dehydrogenase gene (TK1431) (strain MHG1). When MHG1 was cultivated under continuous culture conditions using pyruvate-based medium, a nearly 25% higher specific hydrogen production rate (SHPR) of 35.3 mmol H2 g-dcw-1 h-1 was observed at a dilution rate of 0.31 h-1. We also combined mbh overexpression using an even stronger constitutive promoter from the cell surface glycoprotein gene (TK0895) with disruption of the genes encoding the cytosolic hydrogenase (Hyh) and an alanine aminotransferase (AlaAT), both of which are involved in hydrogen consumption (strain MAH1). At a dilution rate of 0.30 h-1, the SHPR was 36.2 mmol H2 g-dcw-1 h-1, corresponding to a 28% increase compared to that of the host T. kodakarensis strain. Increasing the dilution rate to 0.83 h-1 or 1.07 h-1 resulted in a SHPR of 120 mmol H2 g-dcw-1 h-1, which is one of the highest production rates observed in microbial fermentation
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