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81.
82.
Yoritaka Aoyama Eri Ohmura Akira Yoshida 《Bioscience, biotechnology, and biochemistry》2013,77(11):3125-3131
The effects of dietary composition on lipids in serum and in liver of rats fed with a cystine- excess diet were investigated.When starch was used as the carbohydrate source, the addition of excess-cystine caused an increase in serum cholesterol and phospholipids, and hepatomegaly. Phospholipids in serum of rats fed with a cystine-excess diet containing 5% corn oil were higher than those with a cystine-excess diet that was low in corn oil (0.1 %). The addition of konjac mannan and pectin prevented hypercholesterolemia, and the rise in phospholipids in serum was prevented by the addition of konjac mannan.Liver cholesterol (mg/liver/100 g of body wt.) increased in rats fed with a cystine-excess diet.The addition of excess cystine to a diet containing sucrose as the carbohydrate source resulted in a marked increase of cholesterol in serum and liver, and a decrease of serum triglycerides.The replacement of starch by sucrose in the cystine-excess diet increased liver cholesterol.Lipids, cholesterol, phospholipids and triglycerides in the liver, but not phospholipids, when expressed as mg per g of liver for rats fed with the diets containing sucrose, increased when compared to those for rats fed with the diets containing starch. In contrast, serum triglycerides increased. 相似文献
83.
84.
Growth of Brevibacterium flavum FA-1-30 and FA-3-115, L-lysine producers derived from Br. flavum No. 2247 as S-(2-aminoethyl)-L-cysteine (AEC) resistant mutants, was inhibited by α-amino-β-hydroxyvaleric acid (AHV), and this inhibition was reversed by L-threonine. All the tested AHV resistant mutants derived from FA-1-30 accumulated more than 4 g/liter of L-threonine in media containing 10% glucose, and the best producer, FAB-44, selected on a medium containing 5 mg/ml of AHV produced about 15 g/liter of L-threonine. Many of AHV resistant mutants selected on a medium containing 2 mg/ml of AHV accumulated L-lysine as well as L-threonine, AHV resistant mutants derived from FA-3-115 produced 10.7 g/liter of L-threonine maximally. AEC resistant mutants derived from strains BB–82 and BB–69, which were L-threonine producers derived from Br. flavum No. 2247 as AHV resistant mutants, did not produce L-threonine more than the parental strains, and moreover, many of them did not accumulate L-threonine but L-lysine. Homoserine dehydrogenases of crude extracts from L-threonine producing AHV resistant mutants derived from FA–1–30 and FA–3–115 were insensitive to the inhibition by L-threonine, and those of L-threonine and L-lysine producing AHV resistant mutants from FA–1–30 were partially sensitive.Correlation between L-threonine or L-lysine production and regulations of enzymatic activities of the mutants was discussed. 相似文献
85.
Tomohiko Mori Shigeru Utsumi Hisaji Inaba 《Bioscience, biotechnology, and biochemistry》2013,77(11):2317-2322
Native subunit proteins of glycinin, the acidic and the basic subunits designated as AS1+2, AS2+3, AS4, AS5, and AS6 and BS, respectively, were isolated by DEAE-Sephadex A-50 column chromatography in the presence of 6 m urea and 0.2 m 2-mercaptoethanol.Reconstitution of intermediary subunits involving a disulfide bridge from native acidic and basic subunits was investigated. Formation of the intermediary subunit was observed in combinations between BS and each acidic subunit except AS6. The yields of the reconstituted intermediary subunits differed from one another.Further, formation of the intermediary complexes was observed when native acidic and basic subunits of soybean glycinin and sesame 13 S globulin, respectively (or reverse combinations), were mixed under reductively denatured condition and subjected to the reconstitution procedure. Considerring the overall evidence, we may conclude that the complexes are probably a hybrid intermediary subunit. 相似文献
86.
87.
Takashi Utagawa Hirokazu Morisawa Shigeru Yamanaka Akihiro Yamazaki Fumihiro Yoshinaga Yoshio Hirose 《Bioscience, biotechnology, and biochemistry》2013,77(11):3239-3246
The properties of uridine Phosphorylase (UPase) and purine nucleoside Phosphorylase (PNPase) at high temperature were investigated. Both enzymes were found to be distributed in a wide range of bacteria and were partially purified from Enterobacter aerogenes AJ 11125 by heat treatment, ammonium sulfate fractionation and column chromatographies onDEAE-cellulose and Sephadex G-150. The UPase was purified 109-fold, and it showed an optimum pH of 8.5 and optimum temperature of 65°C, and activity toward uridine, 2′-deoxyuridine, thymidine and uracil arabinoside but not cytidine. The Km values of UPase for uridine were 0.7 mm at 40°C and 1.8 mm at 60°C. The PNPase was purified 83-fold, and it showed an optimum pH of 6.8 and optimum temperature of 60°C, and significant activity toward purine arabinosides as well as purine ribosides. The Km values of PNPase for inosine were 0.8 mm at 40°C and 2.2 mm at 60°C. 相似文献
88.
Toshio Yoshida Shigeru Muraki Hiroshi Kawamura Akira Komatsu 《Bioscience, biotechnology, and biochemistry》2013,77(3):343-352
The main component of Japanese Ho-leaf oil has been shown to be (?)-linalool (80~90%), and the following twenty minor constituents newly have been identified; methyl vinyl ketone, methyl isobutyl ketone, mesityl oxide, β-pinene, myrcene, (+)-limonene, cis- and trans-ocimene, n-hexanol, cis-3-hexenol, cis- and trans-linalool oxide, (?)-1-terpinen-4-ol, (+)-cis and (+)-trans-2,6,6-trimethyl-2-vinyl-5-hydroxytetrahydropyran, citronellol, nerol, (+)-β-selinene, (+)-tagetonol and (?)-trans-hotrienol. (+)-Tagetonol and (?)-trans-hotrienol have been demonstrated to be (+)-3,7-dimethyl-3-hydroxy-1-octen-5-one (III) and (3R)-(?)-trans-3,7-dimethyl-3-hydroxy-1,5,7-octatriene (IX), respectively. 相似文献
89.
The growth of Brevibacterium flavum No. 2247 was inhibited over 90% at a concentration above 1 mg/ml of α-amino-β-hydroxyvaleric acid, a threonine analogue, and the inhibition was reversed by the addition of l-threonine, and to lesser extent by l-leucine, l-isoleucine, l-valine and l-homoserine. l-Methionine stimulated the inhibition. Several mutants resistant to the analogue produced l-threonine in the growing cultures. The percentage of l-threonine producer in the resistant mutants depended on the concentration of the analogue, to which they were resistant. The best producer, strain B-183, was isolated from resistant strains selected on a medium containing 5 mg/ml of the analogue. Mutants resistant to 8 mg/ml of the analogue was derived from strain B-183 by the treatment with mutagen, N-methyl-N’-nitro-N-nitrosoguanidine. Among the mutants obtained, strain BB-82 produced 13.5 g/liter of l-threonine, 30% more than did the parental strain. Among the resistant mutants obtained from Corynebacterium acetoacidophilum No. 410, strain C-553 produced 6.1 g/liter of l-threonine. Several amino acids other than l-threonine were also accumulated, and these accumulations of amino acids were discussed from the view of regulation mechanism of l-threonine biosynthesis. 相似文献
90.
Shigeru Kitayama Takashi Karasawa Akira Matsuyama 《Bioscience, biotechnology, and biochemistry》2013,77(4):628-630
The conversion of prochaetoglobosins as plausible precursors into mycotoxin chaetoglobosin A (1) in a cell-free system of Chaetomium subaffine was unsuccessful. However, reductase activity of the 20-keto-analogues (1), and prochaetoglobosins II (5) and III (6) were found in a microsomal fraction of this fungi. Two new metabolites of chaetoglobosins, named chaetoglobosin Fex (2) and 20-dihydro-chaetoglobosin A (3), were also isolated from the same micro-organisms. Their structures were elucidated by spectroscopic data and chemical transformation. 相似文献