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1.
To reveal the difference of molecular property between structurallysimilar odorless and odoriferous musk compounds, 10 pairs ofbenzenoids (monocyclic-, dicyclic- and tricyclic-) were examined.Molecular structures of all compounds were optimized by MNDO(modified neglect of diatomic differential overlap) consideringconformation. Parameters effective in discriminating two groups,group A of 10 odorless compounds and group B of 10 musk odorcompounds, were searched from 34 candidate parameters by adaptiveleast squares. The best three parameters found were log P value(octanol/water partition coefficient), the longest side lengthof hexahedron circumscribing a molecule, and the parameter whichexpresses structural hindrance to the functional group whena molecule approaches the receptor site. The two groups of compoundswere completely discriminated using these three parameters.  相似文献   
2.
Phosphorylation of clupeine sulfate by purified rat brain calcium-activated, phospholipid-dependent protein kinase (protein kinase C) was studied. In the absence of Ca2+, phosphatidylserine and diolein markedly stimulated its phosphorylation. However Ca2+ did not stimulate but inhibit this phosphorylation about 30% in the presence of phospholipids. Random polymer (Arg, Ser) 3:1 and (Lys, Ser) 3:1 could be phosphorylated by protein kinase C. In the presence of phospholipids Ca2+ is not needed for the phosphorylation of polymer (Arg, Ser) 3:1, while Ca2+ is necessary for polymer (Lys, Ser) 3:1. Non-requirement of Ca2+ on clupeine phosphorylation by protein kinase C is briefly discussed.  相似文献   
3.
Cellulose microfibril orientation patterns in thallus cellsof Chaetomorpha moniligera were studied, and the relationshipbetween the microfibril and the peripheral microtubule arrangementsduring cell-shape modification by colchicine was examined. Inthe cuttings from growing thalli, linearly arranged cylindricalcells developed into cask-shaped cells during 4–6 daysof culture at 27?C. In the cylindrical cells, microfibrils formingthe innermost portion of the wall were arranged alternatelyin longitudinal and transverse directions, but peripheral microtubuleswere always arranged only in a longitudinal direction. Thesefeatures were also noted in the cask-shaped cells. Colchicineat 10–3M and 3?10–3M accelerated both cell expansionand wall thickening with matrix deposition, but the directionsin which both microfibrils and microtubules were arranged werethe same as those of the cylindrical cells. These results indicatethat (1) the microfibril and microtubule arrangements of Chaetomorphaare not necessarily correlated, (2) changes in cell shape ofChaetomorpha are not necessarily accompanied by changes in thearrangement of cell-wall microfibrils, and (3) colchicine playsa role in the loosening and thickening of cell walls by enhancingmatrix deposition. (Received June 2, 1986; Accepted February 13, 1987)  相似文献   
4.
An activated S6 kinase in regenerating rat liver   总被引:1,自引:0,他引:1  
S6 kinase activity was increased in the regenerating liver 5 h after partial hepatectomy compared with sham-operated liver. The protein kinase activity was eluted from DE-52 column at approximately 250 mM NaCl and was not affected by known regulators of protein kinases. The S6 kinase was further purified by chromatography on peptide R1A13-Sepharose 4B and Sephadex G-150. The molecular weight of the enzyme was estimated to be 4.5 X 10(4) by gel filtration. The enzyme catalyzes the phosphorylation of whole histone, mainly H2B histone, at 75 mM Mg2+. These properties are similar to those of a proteolytically modified Ca2+/phospholipid-independent form of protein kinase C.  相似文献   
5.
Summary This is the first full report on the genetic linkage between Japanese Huntington's disease and the DNA markers D4S10 and D4S43/S127. With use of the HindIII, BglI, and EcoRI polymorphisms detected at D4S10, and the combination of all these polymorphisms to give composite haplotypes, nine Japanese Huntington's disease families were found to be informative. Three recombinants for D4S10 were detected in these families, giving a maximum lod score of 1.662 at a of 0.10. Similarly, when we used the MspI and PvuII polymorphisms detected by D4S43/S127, five families gave informative results. No recombinant was detected in these families, giving a maximum lod score of 3.348 at a of 0.00. These results clearly support the view that the Japanese Huntington's disease gene may be identical with the Western gene, in spite of the lower prevalence rate in Japan.  相似文献   
6.
Genetic polymorphism of human serum ribonuclease I (RNase I).   总被引:1,自引:1,他引:0       下载免费PDF全文
One of the human urinary ribonucleases (RNases) was isolated and purified to homogeneity (SDS-PAGE) by means of a series of column chromatographies. The enzyme, designated RNase 1, is a glycoprotein with a molecular weight of approximately 16,000. Rabbit antibody to the purified RNase 1 reacted with human urine and sera, as well as with the purified RNase 1. The genetic polymorphism of serum RNase 1 was studied by polyacrylamide gel isoelectric focusing (IEF-PAGE) in a pH range of 5-8, followed by immunoblotting with antisera specific for RNase 1. Two common phenotypes, RNASE1 1 and RNASE1 1-2, were easily recognized. The homogeneous phenotype, RNASE1 1, consisted of four major bands with different pI values, and the heterogeneous phenotype, RNASE1 1-2, was presumed to represent a mixture of each of the homogeneous phenotypes 1 and 2; however, the other homogeneous phenotype, RNASE1 2, was not detected in our samples. Family studies are in agreement with an autosomal codominant transmission of the two alleles. Population studies indicate that the frequencies of the RNASE 1 and RNASE1 2 alleles are .988 and .012, respectively.  相似文献   
7.
Protease-activated protein kinase in rat liver plasma membrane   总被引:3,自引:0,他引:3  
Upon limited proteolysis with trypsin, a cAMP and Ca2+-independent protein kinase was produced from rat liver plasma membrane. This enzyme showed a multifunctional capacity and phosphorylated calf thymus histone and rat liver ribosomal proteins. The molecular weight was estimated to be 5.0 X 10(4). When plasma membrane was treated with a buffer containing Triton X-100, a proenzyme with a molecular weight of 8.4 X 10(4) was extracted. By tryptic digestion, the proenzyme was converted to an active protein kinase which was similar to the enzyme obtained by the direct digestion of membrane. However, this proenzyme phosphorylated H1 histone in the presence of Ca2+ and phospholipid without proteolytic digestion. These results indicate the existence of a protease-activated protein kinase in rat liver plasma membrane and the proenzyme seems to be same as protein kinase C.  相似文献   
8.
Porcine uterine smooth muscle phosphorylase kinase has been partially purified. The enzyme was activated about 1.5-2.0-fold by exogenous calmodulin. Half maximal stimulation was observed at about 100 nM calmodulin. The activation was dependent on calcium and was maximum at pH 7.5 in the range of pH from 6 to 9. This activation was completely abolished by 100 microM trifluoperazine. The result suggested that unlike slow and cardiac muscles, phosphorylase kinase of uterine smooth muscle showed similar response to calmodulin with that of fast muscle. The physiological role of the calcium and calmodulin-dependent activation of myometrium phosphorylase kinase is briefly discussed.  相似文献   
9.
When pig liver phosphorylase kinase was assayed at various concentrations of Mg2+, about 2-fold stimulation was observed around 2-3 mM Mg2+ (Mg2+/ATP ratio, 20-30) compared with the activity at 0.3 mM Mg2+ (Mg2+/ATP ratio, 3). This stimulation was specific for Mg2+ among the divalent cations tested and the process was reversible. Km values for ATP and phosphorylase b were decreased 3.6- and 9.5-fold, respectively, at 3 mM Mg2+ compared with those obtained at 0.3 mM Mg2+. These results indicate that the activity of liver phosphorylase kinase is influenced by free Mg2+.  相似文献   
10.
A five-month-old Japanese boy was found to have marked glycogen accumulation only in the heart. A survey of enzymes revealed normal activities of phosphorylase, cyclic AMP-dependent protein kinase, acid maltase and amylo-1,6-glucosidase. However, the heart had capacity of activating neither rabbit muscle phosphorylase b nor endogenous phosphorylase b, which was converted to active form only when supplemented rabbit muscle phosphorylase kinase. In contrast to the heart, activities of phosphorylase kinase were found within normal levels in other organ tissues so far tested. These findings indicate that the present case of the cardiac glycogenosis is caused by deficiency of cardiac phosphorylase kinase.  相似文献   
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