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361.
Shohei Sakuda Akira Isogai Tsukasa Makita Shogo Matsumoto Koshi Koseki Hisashi Kodama 《Bioscience, biotechnology, and biochemistry》2013,77(12):3251-3259
The structures of allosamidin (1) and methylallosamidin (2), novel insect chitinase inhibitors, were elucidated as 1 and 2 by acid hydrolysis experiments and analyses of 2d-NMR spectra. They are unique basic pseudotrisaccharides consisting of 2-acetamido-2-deoxy-d-allose (N-acetyl-d- allosamine) and a novel aminocyclitol derivative (3), termed allosamizoline. 相似文献
362.
Akio Ozaki Ryoichi Katsumata Tetsuo Oka Akira Furuya 《Bioscience, biotechnology, and biochemistry》2013,77(10):2925-2930
The chorismate mutase and prephenate dehydratase genes of phenylalanine producing Corynebacterium glutamicum K38, which is resistant to p-fluorophenylalanine and m-fluorophenylalanine, were cloned into plasmid pCE53 in C. glutamicum KY9456, which lacks chorismate mutase and prephenate dehydratase. One of the resultant plasmids, pCmB4, contained a 9.4kb BamHI DNA fragment inserted into the unique BamHl site of pCE53. Plasmid pCmB4 complemented a phenylalanine and tyrosine double auxotroph of C. glutamicum KY9456. Introduction of pCmB4 into C. glutamicum RRL5 resulted in an about ten times increase in chorismate mutase activity. C. glutamicum K38 carrying the plasmid accumulated 19.0mg/ml of phenylalanine (50% increase over the yield of K38). 相似文献
363.
Lyang-ja Lee Akira Kimura Tatsurokuro Tochikura 《Bioscience, biotechnology, and biochemistry》2013,77(4):731-737
UDP-galactose 4-epimerase (EC 5.1.3.2) was purified to a homogeneous state from Bifidobacterium bifidutn grown on a glucose medium. The molecular weight was estimated to be about 90,000. The purified enzyme was very stable and 60 % of its initial activity survived three months of storage at 4°C even at a low protein concentration (0.2 mg/ml). The optimum pH was 9.0, and the Km values for UDP-galactose and UDP-glucose were 5.4 × 10-4 M and 1.4×10 -3 M. UDP was a competitive inhibitor. The enzyme activity was stimulated by various sugar phosphates, but was slightly inhibited by fructose 1,6-diphosphate (FDP). A high concentration of galactose or glucose, which had no effect by itself, inhibited the activity in combination with UMP. The inhibition by FDP was also enhanced by combination with UMP. 相似文献
364.
Toshio Yoshida Akira Komatsu Motoichi Indo 《Bioscience, biotechnology, and biochemistry》2013,77(6):433-437
Menthols were converted to Δ3-menthone enol acetate (VII) via menthones having only one asymmetric carbon atom. It was shown that the optical rotation of menthone enol acetate was proportional to the optical purity of starting menthols. Optical purity of original menthol could, therefore, be determined by optical rotation of menthone enol acetate derived from. 相似文献
365.
Akira Murata Mamoru Odaka Syoichi Mukuno 《Bioscience, biotechnology, and biochemistry》2013,77(2):477-478
Some physicochemical properties and substrate specificity of acid protease B isolated from Scytalidium lignicolum were investigated.The molecular weight determined by the sedimentation equilibrium and sedimentation velocity method was 21,000 and 19,000~20,000, respectively. The isoelectric point was determined as 3.0 using the Tiselius electrophoresis apparatus, 3.2 by isoelectric focusing, respectively.The enzyme did not contain histidine and was composed of 188 amino acid residues. Substrate specificity against various synthetic peptides was different from those of the acid proteases which were inactivated by S–PI and DAN. 相似文献
366.
Hidehiko Yokogoshi Kazutoshi Hayase Akira Yoshida 《Bioscience, biotechnology, and biochemistry》2013,77(10):2503-2506
Formaldehyde dehydrogenase from Pseudomonas putida C-83 was found to contain 7 halfcystine residues per subunit monomer, as checked by the method of performic acid oxidation. Approximately 7 sulfhydryl groups per subunit monomer were titrated with 5,5′-dithiobis(2-nitrobenzoic acid) (DTNB) after denaturation with 8 m urea. In the native enzyme, modification of three sulfhydryl groups per subunit with p-chloromercuribenzoate (PCMB) led to the complete loss of enzyme actiyities for both formaldehyde and n-butanol. Hydrogen-peroxide competitively inhibited the enzyme activity for formaldehyde, while it was only slightly inhibitory to the activity for n-butanol. Both formaldehyde and hydrogen-peroxide protected one sulfhydryl group per subunit monomer from modification with PCMB. Moreover, hydrogen-peroxide was hardly reactive to the enzyme which was preincubated with formaldehyde.From these observations, we conclude that one of three PCMB-reactive sulfhydryl groups is essential for the binding of formaldehyde, and hydrogen-peroxide modifies this sulfhydryl group. 相似文献
367.
Atsuko Kushi Akira Koiwai Daisuke Yoshida Fujio Gotō 《Bioscience, biotechnology, and biochemistry》2013,77(10):2513-2515
Mass spectra of N-trifluoroacetyl n-butyl ester (BTFA) of ornithinoalanine (OAL) and lanthionine (LAN) were compared with those of the BTFA derivatives of lysinoalanine (LAL) and the related amino acids. A difference of m/z 14, corresponding to one methylene group, was found in each pair of characteristic fragments between BTFA-OAL and BTFA-LAL. A temperature-programmed gas-liquid chromatography and gas chromatography-mass spectrometry were developed to analyze BTFA-LAN, BTFA-OAL and BTFA-LAL. More LAL and LAN were formed in α-lactalbumin than lysozyme by high-temperature treatment in water. OAL was detected in lysozyme treated at 100° and 120°C in alkali solution, but not in α-lactalbumin. 相似文献
368.
Masao Fujimoto Akira Kuninaka Hiroshi Yoshino 《Bioscience, biotechnology, and biochemistry》2013,77(9):1555-1561
Nuclease P1 cleaved substantially all phosphodiester bonds in rRNA, tRNA, poly(I), poly(U), poly(A), poly(C), poly(G), poly(I)·poly(C), native DNA and heat-denatured DNA to produce exclusively 5′-mononucleotides. Single-stranded polynucleotides were much more susceptible than double-stranded ones. Influence of pH and ionic strength on the hydrolysis rate significantly varied with the kind of polynucleotides. The enzyme also hydrolyzed 3′-phosphomonoester bonds in 3′-AMP, 3′-GMP, 3′-UMP, 3′-CMP, 3′-dAMP, 3′-dGMP, 3′-dCMP and 3′-dTMP. Ribonucleoside 3′-monophosphates were hydrolyzed 20 to 50 times faster than the corresponding 3′-deoxyribonucleotides. Base preference of the enzyme for 3′-ribonucleotides was in the order of G>A>C≧U, whereas that for 3′-deoxyribo-nucleotides was in the order of C≧T>A≧G. The 3′-phosphomonoester bonds in nucleoside 3′, 5′-diphosphates, coenzyme A and dinucleotides bearing 3′-phosphate were hydrolyzed at a rate similar to that for the corresponding 3′-mononucleotides. Adenosine 2′-monophosphate was highly resistant, being split at less than 1/3,000 the rate at which 3′-AMP was split. 相似文献
369.
370.
Ichizo Shinoda Akira Fushimi Hironobu Kato Hideo Okai Sakuzo Fukui 《Bioscience, biotechnology, and biochemistry》2013,77(9):2587-2596
The primary structure of bovine β-casein contains the partial sequence of -Pro196-Val-Leu-Gly-Pro-Val-Arg-Gly-Pro-Phe-Pro-Ile-Ile-Val209 in the C-terminal portion. We previously reported that the synthetic C-terminal octapeptide, Arg202-Val209, is extremely bitter with its threshold value 0.004 mm, 250 times as strong as that of caffeine. To further investigate the bitter taste of the C-terminal portion of β-casein, we synthesized the C-terminal tetradecapeptide, Pro196-Val209, and some of its fragments. A hydrophobic hexapeptide, Pro196-Val201, was twice as bitter as caffeine. The bitter taste of the decapeptide, Pro200-Val209, was the same as that of Arg202-Val209. Although the tetradecapeptide, Pro196-Val209, was composed of two bitter peptides, Pro196-Val201 and Arg202-Val209, its bitter taste was weaker than that of Arg202-Val209 and its threshold value was 0.015 mm. We suggested that the increase of bitterness in peptides through the introduction of hydrophobic amino acids depended on the number of hydrophobic amino acids added. In addition, the synthetic retro analog of Arg202-Val209 (H-Val-Ile-Ile-Pro-Phe-Pro-Gly-Arg-OH) was not as bitter as Arg202-Val209. This indicated that the sequence of Arg202-Val209 is important for extreme bitterness. 相似文献