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application/pdf, ケトース発色試薬の1つであるSi(IV)-Mo(VI)溶液による希少糖の発色特性(SiMo法)について調べた。本試薬はD-プシコース以外のケトースに対して速やかに発色を示した。これまで問題となっていたD-フルクトースとD-プシコースの比色法による区別を可能にする方法であることがわかった。すなわち，D-プシコースを基質としてケトース3-エピメラーゼ反応により生じたD-フルクトースをSiMo法によって他検体を同時にかつ容易に分析することが可能となった。本法を用いて土壌サンプルより上記酵素を有する微生物のスクリーニングを試みたが陽性株は得られなかった。ポジティブコントロールでは発色が認められたため，本法はケトース3-エピメラーゼ活性の検出に欠かせない方法になるだろう。, A rapid screening method of ketose 3-epimerase, SiMo method, was developed using Si （IV）–Mo （VI） solution. This solution is a yellow color without ketoses. Ketoses except psicose （allulose） was rapidly formed blue 12-molybdosilicate anionic species by Si （IV）–Mo （VI） under acidic pH. Although cysteine-carbazole method, which was specifically detected ketose, shows same level coloration for various ketoses, colorization by Si （IV）–Mo （VI） was different depending on the species of ketoses. By contrast, the formation rate of 12-molybdosilicate anionic species for almost aldoses was very slow. The candidates possessing ketose 3-epimerase activity was screened from various samples. This activity was detected the formation of D-fructose from D-psicose using SiMo method. Positive control such as Shinella sp. NN-6 and recombinant D-tagatose 3-epimerase was detected enzymatic activity using this method. No activity was detected by screened samples in this study, suggesting that positive colonies were not detected in SiMo method due to low detection sensitivity.

Microbial genes encoding cellulases, xylanase, chitinases and hydrogenase were expressed in plants and anaerobic bacteria for effective degradation and conversion of unutilized fibrous biomass to some nutrients and energy compounds. In this review, it was shown that these transgenic plants and bacteria work to convert unutilized biomass to valuable materials. The discussion will expand the effective ways to utilize biomass., 総説 / Review

Congenital bone marrow failure syndromes (BMFSs) are relatively rare disorders characterized by aberrant development in one or more hematopoietic lineages. Genetic alterations have now been identified in most of these disorders although the exact role of the molecular defects has yet to be elucidated. Most of these diseases are successfully managed with supportive care, however, treatment refractoriness and disease progression—often involving malignant transformation—may necessitate curative treatment with hematopoietic stem cell transplantation. Due to the underlying molecular defects, the outcome of transplantation for BMFS may be dramatically different than those associated with transplantation for more common diseases, including leukemia. Given recent improvements in survival and molecular diagnosis of bone marrow failure syndrome patients presenting at adult ages without physical stigmata, it is important for both pediatric and adult hematologists to be aware of the possible diagnosis of BMF syndromes and the unique approaches required in treating such patients.

Rat liver microsomes were treated with snake venom (Naja naja) phospholipase A2. Effect of the degradation of microsomal major phospholipids were studied on the activities of diacylglycerol cholinephosphotransferase (EC 2.7.8.2), diacylglycerol ethanolaminephosphotransferase (EC 2.7.8.1) and diacylglycerol acyltransferase (EC 2.3.1.20). The activities of cholinephosphotransferase and diacylglycerol acyltransferase were rapidly lost following the accumulation of lysophospholipids and free fatty acid, whereas ethanolaminephosphotransferase activity remained unaffected even when over 90% and almost 100% of microsomal phosphatidylcholine and phosphatidylethanolamine, respectively, were hydrolyzed. The inactivation of diacylglycerol acyltransferase occurred much more rapidly than that of cholinephosphotransferase. Microsomal total phospholipids partially reactivated the treated cholinephosphotransferase, but not diacylglycerol acyltransferase. Among phospholipids tested, only phosphatidylcholine was effective. Albumin could partially restore the inactivated diacylglycerol acyltransferase. Ethanolaminephosphotransferase became by the treatment extremely heat-labile, and was restabilized by removal of lysophospholipids and fatty acids from the microsomal membranes. These results indicate that the three diacylglycerol-utilizing enzymes have different dependences on membrane phospholipids and that they are affected differently by the degradation products formed through the action of phospholipase A2.