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101.
M Tanokura H Aramaki K Goto U Hashimoto Y Toyomori K Yamada 《Journal of biochemistry》1986,99(4):1211-1218
Two major isotypes of parvalbumins (PA1 and PA2) have been isolated from the skeletal muscle of bullfrog, Rana catesbeiana. The Mr values were estimated to be 10,100 (PA1) and 11,800 (PA2) by SDS/polyacrylamide gel electrophoresis, and the isoelectric points were determined to be 4.78 (PA1) and 4.97 (PA2) by polyacrylamide gel isoelectric focusing. The amino acid compositions and isoelectric points indicate that PA1 corresponds to Rana esculenta pI 4.50 and Rana temporaria pI 4.75 parvalbumins and PA2 to Rana esculenta pI 4.88 and Rana temporaria pI 4.97 parvalbumins, showing that PA1 is genetically a beta-parvalbumin and PA2 an alpha-parvalbumin. However, in terms of the amino acid compositions, PA1 and PA2 are distinctly different from the corresponding parvalbumins of Rana esculenta or Rana temporaria. The ultraviolet spectra of PA1 and PA2 are consistent with their amino acid compositions. An ultraviolet difference spectrum of the Ca2+-loaded form vs. metal-free form indicates that a Tyr and some Phe residues in PA1 are affected by a conformational change associated with the binding of Ca2+. On electrophoresis in polyacrylamide gel in 14 mM Tris and 90 mM glycine, the Ca2+-loaded form of PA1 migrated twice as fast as the Mg2+-loaded form. Both PA1 and PA2 show increased mobility in the Ca2+-loaded forms, like troponin C but different from calmodulin. 相似文献
102.
T Masaki H Takano-Ohmuro H Iizuka J Okamoto T Obinata 《Journal of biochemistry》1986,100(4):1091-1094
A distinct difference in the 3-methylhistidine (3-MeHis) content and the pH-dependency curve for calcium-activated adenosine triphosphatase (Ca-ATPase) activity was observed between chicken and mammalian cardiac ventricular myosins. The 3-MeHis content and pH dependency of the Ca-ATPase activity of myosins from adult and embryonic chicken cardiac ventricular muscles and chicken fast white and slow red muscles were almost the same. 相似文献
103.
N-Carbamoylsarcosine amidohydrolase, a novel enzyme involved in the microbial degradation of creatinine in Pseudomonas putida 77, was purified 27-fold to homogeneity with a 63% overall recovery through simple purification procedures including successive ammonium sulfate fractionation, DEAE-cellulose chromatography, and crystallization. The relative molecular mass of the native enzyme estimated by the ultracentrifugal equilibrium method is 102,000 +/- 5000, and the subunit Mr is 27,000. The Km and Vm values for N-carbamoylsarcosine are 3.2 mM and 1.75 units/mg protein, respectively. Ammonia, carbon dioxide, and sarcosine were formed stoichiometrically from N-carbamoylsarcosine through the action of the purified enzyme preparation. N-Carbamoyl amino acids with a methyl group or hydrogen atom on the amino-N atom and possessing glycine, D-alanine, or one of their derivatives as an amino acid moiety served well as substrates for N-carbamoylsarcosine amidohydrolase. N-Carbamoylsarcosine, N-methyl-N-carbamoyl-D-alanine, N-carbamoylglycine, and N-carbamoyl-D-alanine were hydrolyzed at relative rates of 100, 12.8, 9.8, and 7.3, respectively, by the enzyme. N-Carbamoyl derivatives of D-tryptophan, D-phenylalanine, and those of some other amino acids including D-phenylglycine and p-hydroxy-D-phenylglycine were also hydrolyzed by the enzyme. For the L-isomers of all N-carbamoyl amino acids tested there was no production of ammonia, carbon dioxide, or the corresponding amino acids due to the action of the enzyme. Cupric, mercuric, and silver ions inhibited the enzyme strongly, and some thiol reagents were also found to be inhibitory. 相似文献
104.
Type IV collagen is a major structural component in basement membranes. It is considerably different from the fibrillar collagens, types I-III. For example, unlike fibrillar collagens, the triple helical domain of type IV collagen is frequently interrupted by nonhelical regions. In this report, we demonstrate several overlapping genomic clones which cover most of the mouse alpha 1(IV) chain. Electron microscopic analysis of R-loops revealed that there were at least 28 exons within 35 kilobases of the gene segment. The sizes of six exons were determined by DNA sequence analysis to be 81, 178, 134, 73, 129, and 213 base pairs. These sizes do not appear to be related to the 54-base pair coding unit which is characteristic of fibrillar collagen exons, suggesting that the alpha 1 type IV collagen gene evolved differently from the fibrillar collagen genes. 相似文献
105.
Phosphorylation and transformation sensitivity of a major collagen-binding protein of fibroblasts 总被引:12,自引:0,他引:12
Using affinity chromatography with immobilized gelatin and native type I collagen, we have identified the major collagen-binding proteins in Nonidet P-40 extracts of chick embryo fibroblasts labeled with [35S] methionine. After washing the gelatin- or collagen-Sepharose beads with high ionic strength buffer, a 47,000-dalton protein was the only major protein besides fibronectin found to bind to these affinity beads. The isoelectric point of this protein was approximately 9.0, with a closely spaced minor spot. The total amount and the synthesis of this collagen-binding protein were both decreased in Rous sarcoma virus-transformed cells. This collagen-binding protein was found to be phosphorylated by incubating intact cells with [32P]orthophosphate. Phosphoamino acid analysis revealed that serine and threonine residues were phosphorylated, but tyrosine was not. Although quantities of the 47,000-dalton protein labeled with [35S]methionine were decreased by a factor 2.5 after transformation, the incorporation of [32P]orthophosphate/unit of protein was 5-7-fold higher in transformed cells. In temperature-sensitive mutant virus-infected cells, the amount of the 47,000-dalton protein was also decreased at the temperature permissive for transformation, and the incorporation of [32P]orthophosphate/protein was also increased. These studies establish that a major membrane-associated collagen-binding protein of fibroblasts is phosphorylated and that it is altered in both total quantity and degree of phosphorylation after malignant transformation. 相似文献
106.
Koji Yamada Masafuni Sasaki Genki Kimura 《In vitro cellular & developmental biology. Plant》1986,22(4):212-216
Summary We examined cellular protein content in four temperature-sensitive (ts) mutants of rat 3Y1 fibroblasts (3Y1tsD123, 3Y1tsF121,
3Y1tsG125, and 3Y1tsH203) under various conditions of culture that affect cell proliferation. When proliferation of the ts
mutants was inhibited at a nonpermissive temperature (39.8°C) in the G1 phase, prominent accumulation of cellular protein occurred in three mutants (3Y1tsF121, 3Y1tsG125, and 3Y1tsH203) but not
in 3Y1tsD123. The over-accumulation of protein at 39.8°C in the former three mutants was inhibited at high cell densities.
At low cell densities there was an upper limit in the protein accumulation at 39.8°C. When the three mutants, proliferation-arrested
at high cell densities at 33.8°C, were replated sparsely in fresh medium and shifted to 39.8°C, proliferation was completely
inhibited whereas over-accumulation of protein occurred. These results indicating dissociation of protein accumulation and
cell proliferation suggest that the two events are regulated by different mechanisms.
This work was supported in part by a Grant-in-Aid for Encouragement of Young Scientists (1984) to K. Y. from the Ministry
of Education, Science, and Culture, Japan. 相似文献
107.
Isolation and characterization of 101-beta-lysozyme that possesses the beta-aspartyl sequence at aspartic acid-101 总被引:1,自引:0,他引:1
H Yamada T Ueda R Kuroki T Fukumura T Yasukochi T Hirabayashi K Fujita T Imoto 《Biochemistry》1985,24(27):7953-7959
In the reaction of the intramolecular cross-linking between Lys-13 (epsilon-NH3+) and Leu-129 (alpha-COO-) in lysozyme using imidazole and 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide hydrochloride [Yamada, H., Kuroki, R., Hirata, M., & Imoto, T. (1983) Biochemistry 22, 4551-4556], it was found that two-thirds of the protein (both the recovered and cross-linked lysozymes) showed a lower affinity than the rest against chitin-coated Celite, an affinity adsorbent for lysozyme. The protein with the reduced affinity was separated on chitin-coated Celite affinity chromatography and found to be slightly different from native lysozyme in the elution position of the tryptic peptide of Ile-98-Arg-112 on reversed-phase high-performance liquid chromatography. In contrast with native lysozyme, the limited hydrolysis of this abnormal tryptic peptide of Ile-98-Arg-112 in 6 N HCl at 110 degrees C gave a considerable amount of beta-aspartylglycine. Therefore, it was concluded that two-thirds of the protein obtained from this reaction possessed the beta-aspartylglycyl sequence at Asp-101-Gly-102. As a result, we obtained four lysozymes from this reaction, the derivative with the beta-aspartyl sequence at Asp-101 (101-beta-lysozyme), the cross-linked derivative between Lys-13 and Leu-129 (CL-lysozyme), the CL-lysozyme derivative with the beta-aspartyl sequence at Asp-101 (101-beta-CL-lysozyme), and native lysozyme. In the ethyl esterification of Asp-52 in lysozyme with triethyloxonium fluoroborate [Parsons, S. M., Jao, L., Dahlquist, F. W., Borders, C. L., Jr., Groff, T., Racs, J., & Raftery, M. A. (1969) Biochemistry 8, 700-712; Parsons, S. M., & Raftery, M. A. (1969) Biochemistry 8, 4199-4205], the same bond rearrangement was detected in the same ratio.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
108.
We have isolated two clones containing 19 kilobases (kb) of the human gene coding for a pro-alpha 1 (II) collagen chain from human lambda genomic DNA libraries. A 3' clone, HC2A, was selected by cross-hybridization with a cDNA clone containing sequences coding for the carboxy propeptide of chick type II procollagen. A second clone, HC2B, was obtained by screening the library with the 5' part of HC2A. The sequence analysis of exon 3 corresponding to the C propeptide reveals the presence of stretches of conserved nucleotides between the human and the chick type II procollagen genes. On Northern blots, the human collagen clone hybridizes strongly to a 5.5-kb RNA for the rat type II procollagen chain. Finally, studies of genomic DNAs from normal individuals reveal the presence of a HindIII and a BamHI polymorphic site at the 3' end of the gene. 相似文献
109.
T Matsuura Y Takeuchi M Kojima S Ueda H Yamada Y Nojyo K Ushijima Y Sano 《Acta anatomica》1985,123(4):207-219
Distributional and morphological features, especially characteristics of the ramification of serotonin-containing supraependymal fibers (SEF), were studied in the ventricular systems of mammals (mouse, rat, guinea pig, rabbit, cat, dog, monkey) by means of a modified peroxidase antiperoxidase technique, using antiserotonin antiserum prepared in our laboratory. SEF were present in all ventricular systems, except on the third ventricle floor and in the choroid plexus. The density of SEF was higher in the smaller species. In the rat, light- and scanning electron microscopical SEF were almost completely abolished 1 week after intraventricular administration of 5,6-dihydroxytryptamine. Ramification of SEF was complicated; the SEF formed a true network with frequent anastomosing. In the ventricular system of rats rendered hydrocephalic by kaolin administration, the mode of axonal branching in the supraependymal plexus could best be analyzed by the scanning electron microscope because the meshes of the plexus were spread out. 相似文献
110.
Squalene analogs such as lycopersene, geranylfarnesyl, digeranyl, and 2-hydroxy-2,3-dihydrosqualene and terpene alcohol derivatives such as farnesyl benzyl ether, farnesyl pivalate, geranylgeranyl pivalate, geranyl pivalate, and geranyl benzyl ether were oxidized by Corynebacterium sp. strain SY-79, which was isolated from soil by using squalene as a carbon source. Lycopersene and geranylfarnesyl gave no major product. Digeranyl, geranyl benzyl ether, and geranyl pivalate gave terminal oxidation products, and 2-hydroxy-2,3-dihydrosqualene, farnesyl benzyl ether, farnesyl pivalate, and geranylgeranyl pivalate were degraded to give lower molecular carboxylic acids. Strain SY-79 showed promising oxidative activities toward acyclic terpenes, although the metabolites obtained were variable, depending upon the structure of the substrate. 相似文献