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101.
Daizo Koga Taiji Imoto Shuhei Tanaka Akio Ide Kazuyoshi Yagishita 《Bioscience, biotechnology, and biochemistry》2013,77(9):1941-1948
The effects of detergents on the lysozyme-catalyzed hydrolysis of Micrococcus lysodeikticus cells were investigated by changing the concentration of Na-phosphate buffer and pH in the presence or absence of sucrose. Also, a parallel study of the hydrolysis of glycolchitin by lysozyme was conducted and compared to the lytic reaction. Electron microscopy was utilized to follow the changes in cell morphology during the various treatments.None of the detergents changed turbidity of the cell suspension. However, they did affect the change in turbidity during lysis in unique ways. SDS, which is an anionic detergent, inhibited lysozyme activity and its addition to the reaction mixture caused a rapid and large decrease in the turbidity. Brij 35 and Triton X-100, which are non-ionic detergents, did not inhibit lysozyme activity, but their presence in the reaction mixture changed the rate of turbidity change. Apparently non-ionic detergents disrupt only the protoplast, while anionic detergents disrupt both the protoplast and the damaged cell. The lytic mechanism of M. lysodeikticus by lysozyme was discussed in detail. 相似文献
102.
Akira K. Tanaka Akio Kobayashi Kyohei Yamashita 《Bioscience, biotechnology, and biochemistry》2013,77(12):2537-2542
1-O-Palmitoyl-d-glucopyranose was prepared by the selective 1-O-acylation of 4,6-O-benzylideneglucose followed by hydrogenolysis of the protecting group. 1-O-Oleoyl-d-glucopyranose was synthesized from the corresponding benzylidene derivative by selective hydrolysis in acetic acid. This procedure constitutes a useful method for the synthesis of 1-O-acyl-d-glucopyranoses containing unsaturated carboxylic acids. However, 4,6-O-benzylidene-l-O-linolenoyl-d-glucopyranose was converted to 3-O-linolenoyl-d-glucopyranose by the acidic hydrolysis due to acyl migration.Synthesized glucosyl esters were inactive in the bean second-internode bioassay. However, it was found that 3-O-linolenoyl-d-glucopyranose had a promoting activity on germination of pollen and growth of pollen tube. 相似文献
103.
Akio Kobayashi Akira Takemura Koichi Koshimizu Hiroshi Nagano Kazuyoshi Kawazu 《Bioscience, biotechnology, and biochemistry》2013,77(2):585-589
Three fungal trichothecenes, verrucarin A, roridin A and 8-β-hydroxyroridin E, were isolated as callus-initiating promoters from Myrothecium sp. 301. These trichothecenes promoted callus induction, synergistically coupled with a low concentration of 2,4-dichlorophenoxyacetic acid. 相似文献
104.
105.
Hiroji Sato Keiichi Konoma Sadao Sakamura Akio Furusaki Takeshi Matsumoto Takao Matsuzaki 《Bioscience, biotechnology, and biochemistry》2013,77(3):795-797
The milk fat globule membrane (MFGM) enclosing fat droplets in bovine milk was isolated, and its effects on hydrolysis of milk fat by lipases were investigated by using a gum arabic-stabilized milk fat emulsion as substrate. The addition of isolated MFGM to the reaction mixture markedly inhibited hydrolysis by pancreatic and microbial (Rhizopus delemer) lipases. The inhibition was completely lost on tryptic digestion of MFGM, suggesting that the protein moiety of MFGM played a role in the inhibition. Soluble glycoprotein (SGP) which was isolated from delipidated MFGM produced marked inhibitory activity. The inhibition by SGP was dependent on substrate concentration, suggesting that the inhibition was at least partly due to coverage and blockage of the substrate surface by SGP. 相似文献
106.
Masateru Miyano Akio Kobayashi Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(9):673-677
d,l-Derrisic acid (IIa, R′: H) was synthesized from d,l-hydroxy dihydrotubanol (Ve) by Hoesch condensation with a nitrile (VI). The possible optical resolution of d,l-IIa was demonstrated by a conventional “reversed resolution” method.This communication and previous works constitute the first total synthesis of natural rotenone (Ia). 相似文献
107.
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
108.
Kazuyoshi Kawazu Jocelyn P. Alcantara Akio Kobayashi 《Bioscience, biotechnology, and biochemistry》2013,77(10):2719-2722
Two insecticidal compounds were isolated from the seeds of Annona squamosa. One was identified as annonin (squamocin) and the other was characterized as a novel dihydroxy-bistetrahydrofuran fatty acid lactone (acetogenin) with 35 carbons. These two compounds were toxic to eggs, larvae and adults of the fruitfly. 相似文献
109.
Synthesis of 9-β-d-glucopyranosyl-adenine-6′-phosphate is described. The method developed here involves the process of condensation of base (chloromercuri-6-benzamidopurine) (I) with phosphorylated sugar (2,3,4-tri-O-acetyl-6-diphenylphosphoryl-α-d-glucopyranosyl bromide) (II). This reaction gives crystalline 6-benzamido-9-(2′,3′,4′-tri-O-acetyl-6′-diphenylphosphoryl-β-d-glucopyranosyl)-purine (III) in high yield, which is converted to the desired nucleotide by alkaline hydrolysis. 相似文献
110.
Akio Kobayashi Kyohei Yamashita Kohei Ohshima Izuru Yamamoto 《Bioscience, biotechnology, and biochemistry》2013,77(12):1961-1965
Allethrin-(E)-Ol (IV), allethrin-(E)-al (V) and allethrin-(E)-acid (VI), the metabolites of allethrin (III) in the insect body, were synthesized. Their low toxicities to houseflies seem to support the hypothesis that they are products of the detoxication process of allethrin. 相似文献