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991.
It has been demonstrated regarding the formation of ketosphingosine base that the enzymatic condensation of palmitoyl-CoA with serine in the particulate preparation from rat liver produces only ketodihydrosphingosine in the absence of flavin nucleotide but produces ketosphingosine as well as ketodihydrosphingosine in the presenee of flavin nucleotide. The findings suggest that ketodihydrosphingosine is formed first from the enzymatic reaction of palmitoyl-CoA with serine and then converted to ketosphingosine by dehydrogenation with the flavin enzyme. 相似文献
992.
Takashi Utagawa Hirokazu Morisawa Shigeru Yamanaka Akihiro Yamazaki Yoshio Hirose 《Bioscience, biotechnology, and biochemistry》2013,77(9):2711-2717
The microbial synthesis of some purine 2′-amino-2′-deoxyribonucleosides from purine bases and 2′-amino-2′-deoxyuridine is described. Various bacteria, especially Erwinia herbicola, Salmonella schottmuelleri, Enterobacter aerogenes and Escherichia coli, were able to transfer the aminoribosyl moiety of 2′-amino-2′-deoxyuridine to purine bases (transaminoribosylation) in the presence of inorganic phosphate. The optimum conditions for the reaction were pH 7.0 and 63°C. No reaction was observed in the absence of inorganic phosphate and the optimum concentration of it was around 30 mm. Adenine, guanine, 2-chlorohypoxanthine and hypoxanthine were transformed to the corresponding 2′-amino-2′-deoxyribonucleosides by the catalytic activity of the wet cell paste of Enterobacter aerogenes AJ 11125. The enzymatically synthesized purine 2′-amino-2′-deoxyribonucleosides were isolated and identified by physicochemical means. 2′-Amino-2′-deoxyadenosine strongly inhibited the growth of Hela cells in tissue culture, and the ED50 was 2.5μ/ml. 相似文献
993.
Kazuo Miura Shigeru Ōtsuka Kōichiro Honda 《Bioscience, biotechnology, and biochemistry》2013,77(4):219-222
The changes of metabolisms in the calf, dog and rat following administeration of fluoroacetate were studied. It was found that citrate is accumulated in the tissues, and increased amounts of acetone bodies are excreted in the urine of the animals which received fluoroacetate, and their urinary nitrogen also increases. All these abnormal accumulations and excretions of the rat after injection of fluoroacetate diminish within 24hrs., suggesting the decrease of the toxity or the excretion of the poison substance.Significant amounts of organic fluorine compounds were detected in various tissues of fluoroacetate-treated calves.The lethal dose limit of fluoroacetate for the calf could not be determined. As for the dog, 0.02 mg/kilo of fluoroacetate seemed to be fatal. 相似文献
994.
Atsushi Yokota Shigeru Oita Shoichi Takao 《Bioscience, biotechnology, and biochemistry》2013,77(8):2037-2044
A new process for tryptophan production was established using a lipoic acid auxotrophic mutant, Enterobacter aerogenes l-12, which has both pyruvic acid productivity and tryptophanase activity. The process consists of the production of pyruvic acid from glucose by the washed cells and the subsequent conversion of the acid to tryptophan by the tryptophanase itself in the presence of indole and NH4C1.To prepare washed cells of which the tryptophanase activity and the pyruvic acid productivity were both high, it was best to culture the strain in a medium containing 1 % Polypepton, 0.2 % glucose, 3 μg/1 dl-lipoic acid, 0.05 % l-tryptophan, and mineral salts. The optimum composition of the reaction mixture for the pyruvic acid production by the washed cells was established. Under these conditions, 17 g/1 of pyruvic acid was accumulated from 5 % glucose after 36 hr of incubation. Thus, the conversion of the pyruvic acid to tryptophan was done by adding indole, NH4C1, pyridoxal-5′-phosphate, Triton X-100, and KOH to adjust the pH to 9.0 to the above reaction mixture. As a result, the pyruvic acid was rapidly converted to tryptophan, and the concentration of 14 g/1 was obtained after 36 hr (total 72 hr). 相似文献
995.
Taichi Usui Shigeru Tsushima Naotaka Yamaoka Kazuo Matsuda Katura Tuzimura Hiroshi Sugiyama 《Bioscience, biotechnology, and biochemistry》2013,77(7):1409-1410
A 24 kDa protein was isolated from tartary buckwheat seeds by using chromatography of Superdex 75 gel filtration and Resource Q ion-exchange column. SDS-PAGE and Sephacryl S-200 gel filtration were used to provide information about the molecular mass of the protein purified from tartary buckwheat. The protein was composed of 215 amino acid residues and showed strong IgE binding activity in an ELISA test to the sera colleted from two patients allergic to buckwheat. These results suggested that the purified 24 kDa protein from tartary buckwheat seeds was an important functional protein and was relatively specific for buckwheat-allergic patients. It should be a very useful tool in the diagnosis of buckwheat allergy in the future. 相似文献
996.
Kazuaki Kitano Kazuhiko Kintaka Shigeru Suzuki Kazuyoshi Katamoto Kiyoshi Nara Yoshio Nakao 《Bioscience, biotechnology, and biochemistry》2013,77(9):1761-1762
The absolute configuration of a phytoalexin “Safynol” (3E, 11E)-3, 11-tridecadiene-5, 7, 9-triyne-l, 2-diol (I), separated from Phytophthora drechsleri-infected safflower (Carthamus tinctorius L.) was confirmed. (R) and (S)-safynol were synthesized from 2, 3-O-isopropyli- dene-(S)- and (R)-glyceraldehyde respectively, and the (R) configuration was assigned to the natural product. The inhibitory effects of (R)- and (S)-safynol on mycelial growth of five fungi were almost the same and their ED50 values ranged from 6 to 70 ppm. 相似文献
997.
Koki Kodama Shigeru Nakatani Kazuyoshi Umehara Katsumi Shimizu Yasuji Minoda Koichi Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(9):1320-1324
Five substances, water soluble organic sulfur compounds, produced from dibenzothiophene by such bacteria as Pseudomonas jianii or Ps. abikonensis were isolated from culture broth. Three products of them were identified as 3-hydroxy-2-formyl-benzothiophene, dibenzothiophene-5-oxide and 3-oxo-2[3′-hydroxy-thionaphthenyl-(2)-methylene]dihydrothionaphthene respectively. 相似文献
998.
Yukio Akiyama Shigeki Nishikawaji Shigeru Eda Hiroshi Tanaka Akio Ohnishi Kunio Katō 《Bioscience, biotechnology, and biochemistry》2013,77(4):1193-1194
A novel monoterpene, 2(E)-(4-methyl-3-pentenyl)butenedial (α-acaridial (1) for the trivial name), was isolated from the secretion of the acarid mite Tyrophagus perniciosus. The structure was clarified in the light of spectral data, and the geometry of the double bond in the butenedial moiety was assigned based on the γ-deshielding effect on a methylene and on an aldehyde group. Coupling the Grignard reagent (CH3)2C =CHCH2CH2MgBr to THP-OCH2(C = O)CH2CH2O-THP, and dehydration and deprotection of the OH groups gave α-(E)- and α-(Z)-acaridiol, which were fully assigned byMS and NMR. Matching the spectral data of the synthetic alcohols with those of the alcohol derived from the natural product, or of natural acaridial with those of synthetic α-(E)- and α-(Z)-acaridial, corroborated beyond all doubt the structure of this new monoterpene dial. 相似文献
999.
1000.