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Using Toyopearl and cyclohexane: cyclohexanol solvent, fourCl-containing Chls were separated from 36Cl-labeled cells ofthe blue-green, Plectonema boryanum. In normally grown cells,all four Cl-containing chlorophylls amounted to less than 1/2,000of the total Chi and about 1/50 of P700, values much lower thanpreviously reportedcontents of Chi RC I, and varied from algato alga. The level of Cl-containing Chi was markedly enhancedwhen the cells were poisoned with methyl viologen. These resultssuggests that these Cl-containing Chls are not related to thereaction center of PS I. (Received June 23, 1987; Accepted September 17, 1987) 相似文献
4.
Human skeletal muscle contains two major aminopeptidases: an anion-activated aminopeptidase B and an aminopeptidase M-like enzyme 总被引:1,自引:0,他引:1
S Ishiura T Yamamoto M Yamamoto M Nojima T Aoyagi H Sugita 《Journal of biochemistry》1987,102(5):1023-1031
Two major aminopeptidases, an aminopeptidase B and an aminopeptidase M-like enzyme, were purified from human skeletal muscle by DEAE-cellulose, HPLC gel filtration, and hydroxyapatite column chromatographies. The purified aminopeptidase B exhibits a molecular weight of 76,000 under both native and denaturing conditions. The activity of the aminopeptidase B is regulated by C1 ions and other anions in vitro. On the other hand, the aminopeptidase M-like enzyme is a monomeric protein having a molecular weight of 96,000. It is capable of significantly cleaving Phe-, Leu-, Arg-, and Ala-aminoacyl bonds in the presence of 2-mercaptoethanol. The pH optima for both enzymes are around 7.0, and bestatin is an effective inhibitor of both enzymes. 相似文献
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Endothelin-3 is a novel neuropeptide: isolation and sequence determination of endothelin-1 and endothelin-3 in porcine brain 总被引:4,自引:0,他引:4
O Shinmi S Kimura T Sawamura Y Sugita T Yoshizawa Y Uchiyama M Yanagisawa K Goto T Masaki I Kanazawa 《Biochemical and biophysical research communications》1989,164(1):587-593
The molecular forms of endothelin (ET) related peptides were investigated in porcine brain by using high performance liquid chromatography coupled with three specific radioimmunoassays. ET-1 and its oxidized form were isolated and sequenced as in the case of porcine spinal cord. A very small amount of big ET-1 (1-39) and its C-terminal fragment (big ET-1 (22-39] were also detected. Furthermore, immunoreactive (ir)-ET-3 was isolated and sequenced; its partial primary structure was identical to that of human (rat) ET-3. The concentrations of ir-ET-1 and ir-ET-3 in porcine brain were 140 fmol/g tissue and 5 fmol/g tissue, respectively. These results indicate that besides ET-1, ET-3 is a novel neuropeptide in the central nervous system. 相似文献
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Presence of endothelin-1 in porcine spinal cord: isolation and sequence determination 总被引:2,自引:0,他引:2
O Shinmi S Kimura T Yoshizawa T Sawamura Y Uchiyama Y Sugita I Kanazawa M Yanagisawa K Goto T Masaki 《Biochemical and biophysical research communications》1989,162(1):340-346
We investigated the molecular forms of endothelin (ET) related peptides in porcine spinal cord by high performance liquid chromatography coupled with radioimmunoassays using three antisera raised against ET-1 and C-terminal fragments of ET-1 and big ET-1. ET-1 and its oxidized form were isolated as major immunoreactive peptides and sequenced. Furthermore, immunoreactivities like ET-3 and big ET-1(22-39) (contents: less than 8% and less than 1% of ET-1, respectively) were detected based on their chromatographic retention times and characteristics of immunoreactivity to the antisera. Big ET-1 was only scarcely detected. Immunohistochemical study showed the presence of ET-1-like immunoreactivity in motoneurons, dorsal horn neurons and dot- and fiber-like structures in the dorsal horn of lumbar spinal cord. These results indicate that ET-1 is present not only in endothelial cells but also in spinal cord, and that big ET-1 is converted into ET-1 in spinal cord by specific processing between Trp21-Val22. The data also indicate that ET-1 may act as a neuropeptide in the central nervous system. 相似文献
8.
N. Shiratsuki O. Uyama O. Kitada N. Suenaga H. Nakamura M. Sugita Y. Hayashi S. Yamamoto 《Prostaglandins, leukotrienes, and essential fatty acids》1990,40(4):285-289
To study the role of leukotriene C4(LTC4) and the effect of hydrocortisone and aminophylline on plasma LTC4 levels in patients with asthmatic attacks, we measured LTC4 in plasma of 18 asthmatics during a wheezing attack and of 7 normal subjects. Blood samples were obtained before and after treatment with aminophylline and/or hydrocortisone injections. We extracted LTC4 using a Sep-Pak C18 cartridge for the measurement of LTC4 by radioimmunoassay. The plasma levels of immunoreactive LTC4 (i-LTC4) of the normal subjects were 142 +/- 25 pg/ml (n = 7), while those of nonatopic type asthmatic patients with wheezing attacks were 208 +/- 68 pg/ml (n = 15) (p less than 0.01). Before and after treatment with both hydrocortisone succinate (100 mg) and aminophylline (250 mg), 6 asthmatic patients with wheezing attacks had a mean plasma level of i-LTC4 181 +/- 24 and 132 +/- 18 pg/ml (p less than 0.01), respectively. On the other hand, the treatment with aminophylline 250 mg alone increased the i-LTC4 levels from 178 +/- 19 pg/mg to 213 +/- 16 pg/mg (n = 6)(p less than 0.05), while treatment with hydrocortisone succinate 100 mg decreased the i-LTC4 level 0.05 from 284 +/- 99 pg/ml to 249 +/- 85 pg/ml (n = 4)(p less than 0.05). In conclusion, the present study shows that the i-LTC4 level in venous blood of patients with asthmatic attacks is decreased significantly by treatment with hydrocortisone succinate. 相似文献
9.
A new cytochrome P-450 isozyme, P-450C-M/F, has been purified from untreated rat liver microsomes. The purified preparation was electrophoretically homogeneous and contained 12-15 nmol of P450/mg of protein and had a minimum molecular weight of 48,500. The NH2-terminal amino acid sequence of P-450C-M/F was different from that of other P-450's. Immunoblot analysis of microsomes demonstrated that P-450C-M/F was present in the liver of untreated male as well as female rats. Treatment of rats with phenobarbital, 3-methylcholanthrene, or beta-naphthoflavone did not induce P-450C-M/F. Cytochrome P-450C-M/F exhibited little activities of 7-ethoxycoumarin and 7-ethoxyresorufin O-deethylation or hydroxylation of arylhydrocarbon, testosterone, androstenedione, and progesterone. In contrast, it was highly active in N-demethylation of ethylmorphine and benzphetamine and in 2- and 16 alpha-hydroxylation of estrogens, particularly that of estradiol. These studies establish that cytochrome P-450C-M/F is constitutively present in both male and female rats and suggest that it may be involved in the oxidative metabolism of estradiol, particularly in the formation of estriol, the uterotropic metabolite of estradiol. 相似文献
10.
Improved method for the isolation and preliminary characterization of human DAF (decay-accelerating factor) 总被引:5,自引:0,他引:5
DAF (decay-accelerating factor) is one of the integral membrane proteins of erythrocytes, and is considered to play an important role in the regulation of complement activation. The purification of DAF has been impeded by the difficulty in removing glycophorin. We devised an effective method for removing glycophorin. Through the limited trypsinization of stromata prior to the extraction of DAF, glycophorin was readily digested so that the DAF could be purified free of glycophorin by DEAE-Sephacel and Bio-Gel A 0.5 m chromatographies. On SDS-PAGE, DAF from trypsinized stromata showed the same mobility as that from native stromata: its molecular weight was estimated to be about 70 kDa. Amino acid analysis of DAF showed high contents of serine and glutamic acid. The amino-terminal sequence of DAF prepared by the present method, determined for the 29 residues, did not show significant homology with that of glycophorin. 相似文献