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1.
T Yoshimoto K Takahashi A Ajima A Matsushima Y Saito Y Tamaura Y Inada 《FEBS letters》1985,183(1):170-172
Modified asparaginase, in which 4 tryptophan residues were modified with 2-hydroxy-5-nitrobenzyl bromide, had little enzymic activity and retained immunoreactivity [(1976) FEBS Lett. 65, 11-15]. Addition of IgG or its Fab towards asparaginase to the modified asparaginase gave rise to marked enhancement of the enzymic activity. Native asparaginase (4 subunits) lost the enzymic activity due to dissociation into subunits by dilution of the enzyme solution. However, in the presence of Fab, asparaginase did not lose enzymic activity on dilution, probably due to no dissociation into subunits occurring. 相似文献
2.
A. Ajima T. Yoshimoto K. Takahashi Y. Tamaura Y. Saito Y. Inada 《Biotechnology letters》1985,7(5):303-306
Summary A hydrophobic substrate, 10-hydroxydecanoic acid having two functional groups (–OH and –COOH) in the molecule, was polymerized by ester bond formation with the polyethylene glycol-modified lipase in a transparent benzene solution. The polymer of 10-hydroxydecanoic acid was linearly elongated under a quite mild condition. 相似文献
3.
Yoshimoto T. Takahashi K. Nishimura H. Ajima A. Tamaura Y. Inada Y. 《Biotechnology letters》1984,6(6):337-340
Summary Lipoprotein lipase modified with polyethylene glycol dissolved in benzene, and catalyzed various reactions of ester synthesis, ester exchange and aminolysis. This modified enzyme had a high stability; 50% of the initial enzymic activity were retained after about 3 months-storage in benzene at room temperature. We can repeatedly re-use the enzyme by recovering from benzene solution; the enzyme precipitates upon addition of n-hexane(or petroleum ether). 相似文献
4.
Polyethylene glycol-modified catalase exhibits unexpectedly high activity in benzene 总被引:1,自引:0,他引:1
K Takahashi A Ajima T Yoshimoto Y Inada 《Biochemical and biophysical research communications》1984,125(2):761-766
Bovine liver catalase with molecular weight of 248,000, which consists of four subunits, was modified with 2,4-bis(o-methoxypolyethylene glycol)-6-chloro-s-triazine(activated PEG2). The modified catalase became soluble in organic solvents such as benzene by increasing the degree of modification of amino groups in the enzyme with activated PEG2. The enzymic activity of the modified catalase in benzene, in which 42% of the total amino groups were coupled with the modifier, was unexpectedly high in comparison with the activity of non-modified catalase in aqueous system. The absorption spectrum of the modified catalase in benzene showed the characteristic pattern of a haem protein with Soret band at 405 nm. The temperature-activity profile of the modified catalase in benzene was clarified and its activation energy was estimated to be 1900 cal/mol. 相似文献
5.
6.
A Ajima S G Cao K Takahashi A Matsushima Y Saito Y Inada 《Biotechnology and applied biochemistry》1987,9(1):53-57
Hemin, having two carboxyl groups, was coupled with alpha-(3-aminopropyl)-omega-methoxypoly(oxyethylene) through the acid-amide bond formed with carbodiimide. The modified hemin catalyzed the peroxidase reaction in 1,1,1-trichloroethane using benzoyl peroxide or peroxides in unsaturated fatty acids as the hydrogen acceptor and leuco crystal violet as the hydrogen donor. A basic study on quantitative microanalysis of the lipid peroxides was attempted. 相似文献
7.
Tokimatsu Koji Tang Longlong Yasuoka Rieko Ii Ryota Itsubo Norihiro Nishio Masahiro 《The International Journal of Life Cycle Assessment》2020,25(9):1710-1736
The International Journal of Life Cycle Assessment - Despite the long-standing demand for research on dynamic lifecycle assessment (LCA) for policymaking, only a few studies have addressed this... 相似文献
8.
Aida Rieko Hagiwara Keitaro Okano Kazunori Nakata Kyoko Obata Yuho Yamashita Takahiro Yoshida Kaoru Hagiwara Hiromi 《Molecular biology reports》2021,48(3):2291-2297
Molecular Biology Reports - Apigenin is a flavonoid with antioxidant and anticancer effects. It has been reported that apigenin inhibits proliferation, migration, and invasion and induces apoptosis... 相似文献
9.
Shahid N. Khan John D. Persons Michel Guerrero Tatiana V. Ilina Masayuki Oda Rieko Ishima 《Protein science : a publication of the Protein Society》2021,30(3):571
A clinically‐relevant, drug‐resistant mutant of HIV‐1 protease (PR), termed Flap+(I54V) and containing L10I, G48V, I54V and V82A mutations, is known to produce significant changes in the entropy and enthalpy balance of drug‐PR interactions, compared to wild‐type PR. A similar mutant, Flap+(I54A), which evolves from Flap+(I54V) and contains the single change at residue 54 relative to Flap+(I54V), does not. Yet, how Flap+(I54A) behaves in solution is not known. To understand the molecular basis of V54A evolution, we compared nuclear magnetic resonance (NMR) spectroscopy, fluorescence spectroscopy, isothermal titration calorimetry, and enzymatic assay data from four PR proteins: PR (pWT), Flap+(I54V), Flap+(I54A), and Flap+(I54), a control mutant that contains only L10I, G48V and V82A mutations. Our data consistently show that selection to the smaller side chain at residue 54, not only decreases inhibitor affinity, but also restores the catalytic activity. 相似文献
10.
Toshiaki Shimizu Yayoi Satoh Hiromichi Syoji Rieko Tadokoro Kouichi Sinohara Satoshi Oguchi 《Free radical research》2013,47(10):1067-1070
Very low birth weight (VLBW) infants are known to have poorly developed antioxidant system and may be at increased risk for radical damage. Previous studies have reported higher levels of lipid peroxide products in lipid emulsion used for parenteral nutrition. To examine the direct effects of parenteral lipid infusion on DNA damage in VLBW infants, we measured urinary 8-hydroxydeoxyguanosine (8-OHdG) levels in VLBW infants before, during, and after the parenteral lipid infusion. In both the lipid-infused and lipid-free groups, urinary 8-OHdG excretion levels at 14 days old were significantly ( p <0.01) lower than those at 2 and 7 days old. However, there were no significant differences in urinary 8-OHdG excretion levels between the lipid-infused and lipid-free groups at 2, 7, and 14 days old. Our results suggest that parenteral lipid infusion does not cause oxidative DNA damage, but irrespective of the infusion DNA damage during the first week of life is enhanced when compared with 14 days after birth in VLBW infants. 相似文献