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991.
Katsumi Shibata Chifumi Nakata Tsutomu Fukuwatari 《Bioscience, biotechnology, and biochemistry》2016,80(2):304-312
B-group vitamins are involved in the catabolism of 2-oxo acids. To identify the functional biomarkers of B-group vitamins, we developed a high-performance liquid chromatographic method for profiling 2-oxo acids in urine and applied this method to urine samples from rats deficient in vitamins B1 and B6 and pantothenic acid. 2-Oxo acids were reacted with 1,2-diamino-4,5-methylenebenzene to produce fluorescent derivatives, which were then separated using a TSKgel ODS-80Ts column with 30 mmol/L of KH2PO4 (pH 3.0):acetonitrile (7:3) at a flow rate of 1.0 mL/min. Vitamin B1 deficiency increased urinary levels of all 2-oxo acids, while vitamin B6 deficiency only increased levels of sum of 2-oxaloacetic acid and pyruvic acid, and pantothenic acid deficiency only increased levels of 2-oxoisovaleric acid. Profiles of 2-oxo acids in urine samples might be a non-invasive way of clarifying the functional biomarker of B-group vitamins. 相似文献
992.
Katsumi Shibata Marika Yamazaki Yukiyo Matsuyama 《Bioscience, biotechnology, and biochemistry》2016,80(11):2208-2216
The present study was conducted to survey functional biomarkers for evaluation of niacin nutritional status. Over 500 enzymes require niacin as a coenzyme. Of these, we chose the tryptophan degradation pathway. To create niacin-deficient animals, quinolinic acid phosphoribosyltransferase-knock out mice were used in the present study because wild type mice can synthesize nicotinamide from tryptophan. When the mice were made niacin-deficient, the urinary excretion of xanthurenic acid (XA) was extremely low compared with control mice; however, it increased according to the recovery of niacin nutritional status. The urinary excretion of kynurenic acid (KA) was the reverse of XA. Kynurenine 3-monooxygenase, which needs NADPH, was thought to be suppressed by niacin deficiency. Thus, we calculated the urinary excretion ratio of XA:KA as a functional biomarker of niacin nutrition. The ratio increased according to recovering niacin nutritional status. Low values equate with low niacin nutritional status. 相似文献
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996.
Hiroyuki Nojima Kazuhiko Kanou Genki Terashi Mayuko Takeda-Shitaka Gaku Inoue Koichiro Atsuda Chihiro Itoh Chie Iguchi Hajime Matsubara 《BMC structural biology》2016,16(1):11
Background
We comprehensively analyzed X-ray cocrystal structures of dipeptidyl peptidase IV (DPP-4) and its inhibitor to clarify whether DPP-4 alters its general or partial structure according to the inhibitor used and whether DPP-4 has a common rule for inhibitor binding.Results
All the main and side chains in the inhibitor binding area were minimally altered, except for a few side chains, despite binding to inhibitors of various shapes. Some residues (Arg125, Glu205, Glu206, Tyr662 and Asn710) in the area had binding modes to fix a specific atom of inhibitor to a particular spatial position in DPP-4. We found two specific water molecules that were common to 92 DPP-4 structures. The two water molecules were close to many inhibitors, and seemed to play two roles: maintaining the orientation of the Glu205 and Glu206 side chains through a network via the water molecules, and arranging the inhibitor appropriately at the S2 subsite.Conclusions
Our study based on high-quality resources may provide a necessary minimum consensus to help in the discovery of a novel DPP-4 inhibitor that is commercially useful.997.
998.
Christina M. Sloan-Heggen Amanda O. Bierer A. Eliot Shearer Diana L. Kolbe Carla J. Nishimura Kathy L. Frees Sean S. Ephraim Seiji B. Shibata Kevin T. Booth Colleen A. Campbell Paul T. Ranum Amy E. Weaver E. Ann Black-Ziegelbein Donghong Wang Hela Azaiez Richard J. H. Smith 《Human genetics》2016,135(4):441-450
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M Uyeda H Oshima K Nishi K Suzuki S Yahara T Nohara M Shibata 《Journal of enzyme inhibition》1989,2(4):279-294
M-GTFI, an inhibitor of glucosyltransferase from S. mutans was produced by Micromonospora narashinoensis strain No. 731. The isolation procedure for M-GTFI was improved and established for spectroscopic analyses, and some properties of the inhibitor were investigated. The structure of M-GTFI was shown to be trisodium [2-sulphonato-(E)-9-undecenyll-oxacyclotriacont-(E)-3- en-2-one, 16, 18-bis sulphonate. The chemical structure of M-GTFI was therefore similar to that of izumenolide which is a beta-lactamase inhibitor containing sulfate ester groups in its molecule. The inhibitory characteristics of M-GTFI were parallel to that of other inhibitory compounds containing sulphate esters but the spectrum of activity was wider. 相似文献