PubMed Health⌕ Search

Biomedical subjects

T Hirabayashi

Publications and source records attributed to T Hirabayashi.

At least 127 records · Page 7Linked to original sources
PubMed1980

Isolation and some properties of a new fiber-forming protein from Tetrahymena pyriformis.

Isolation and characterization of a fibrous protein component which might be associated with contractile ring of a dividing Tetrahymena cell were attempted by making use of coprecipitation of the protein with rabbit skeletal muscle myosin. The protein was purified to homogeneity by ammonium sulfate fractionation between 40--70% saturation and column chromatography of Sephadex G-200, starting from KCl-extract of Tetrahymena acetone powder. Its molecular weight was calculated to be 38,000, based on the electrophoretic mobility in sodium dodecyl sulfate (SDS)-polyacrylamide gel, whereas molecular weight of its native state was determined to be 140,000 by gel filtration on Sephadex G-200, and its sedimentation coefficient was about 9S as estimated by sucrose density gradient centrifugation. The latter was a particle of 7.7 nm in diameter under an electron microscope and supposed to be a tetramer of the 38,000-dalton protein. The protein is considered to be a new, unique protein, since it is definitely different from the ubiquitous non-muscle actin in molecular weight, polymerizability in KCl solution and amino acid composition, and it also different from tropomyosin and tubulin in immunological characteristics and amino acid composition.

Actins↗
PubMed1980

Localization of a new fiber-forming protein within Tetrahymena pyriformis.

As a step to study the biological function of a new protein, fiber-forming protein-38,000 (FFP-38), which was previously isolated from Tetrahymena pyriformis, its intracellular localization was investigated by using antiserum specific for FFP-38. Double immunodiffusion tests revealed that the anti-FFP-38 serum reacted with the protein(s) in isolated organelles such as oral apparatus, pellicles and mitochondria, to give rise to a precipitin line confluent with the line formed between the antiserum and the FFP-38. Furthermore, indirect fluorescent antibody staining showed that fluorescence was intensely localized in the oral apparatus and faintly distributed throughout the cytoplasm. In particular, distinct fluorescence was found along the division furrow of dividing Tetrahymena.

Animals↗
PubMed1979

Troponin C-like protein in chicken gizzard muscle.

1. A troponin C-like protein was prepared from frozen chicken gizzard by preparative polyacrylamide gel electrophoresis and its apparent molecular weight was estimated to be about 15,500 daltons. 2. In urea gel electrophoresis, the mobility of the troponin C-like protein increased slightly in the presence of Ca2+, like that of skeletal muscle troponin C. On the other hand, the mobility of the the troponin C-like protein in glycerol gel electrophoresis, unlike that of skeletal muscle troponin C, was significantly decreased by Ca2+. 3. In alkaline gel electrophoresis, the troponin C-like protein formed a Ca2+-dependent complex with troponin I or troponin T from skeletal muscle. 4. The troponin C-like protein could neutralize the inhibitory effect of skeletal muscle troponin I on the Mg2+-activated ATPase of actomyosin from rabbit skeletal muscle, but could not confer Ca2+-sensitivity on the actomyosin in the presence of troponin I and troponin T from skeletal muscle.

Adenosine Triphosphatases↗
PubMed1978

Existence of common antigenic sites in tropomyosins.

1. Tropomyosins were extracted from vertebrate and invertebrate muscles, and their immunolo;ical characteristics were compared using antisera against tropomyosins from chicken skeletal and cardiac muscles. 2. Antigenic sites common to those of chicken skeletal muscle tropomyosin were found in all the tropomyosins tested, although the reactions of these common antigenic sites in an immunodiffusion test were weak in tropomyosins from phylogenetically distant animals. 3. An immunological difference was found between alpha-tropomyosins from chicken cardiac muscle and rabbit cardiac muscle. Thus they had specific antigenic sites in addition to the common ones. 4. A component was found in a 1 M KCL extract of Tetrahymena pyriformis which reacted with antiserum against chicken skeletal muscle tropomyosin.

Animals↗
PubMed1978

The functional characteristics conserved in tropomyosins.

1. Tropomyosin, one of the regulatory proteins in muscle contraction, was prepared from chickens, rabbits, frogs, shrimps, and shellfish, and conserved characteristics were studied using an enzymological technique. 2. All tropomyosins tested, irrespective of their sources, were found to have the ability to mediate the inhibitory activity of rabbit troponin toward rabbit Mg2+-activated actomyosin ATPase (Mg2+-ATPase) activity in the absence of Ca2+ ions. 3. The effect of tropomyosin on the Mg2+-ATPase activity in the presence of Ca2+ ions varied, depending on the source, and this variation appeared to reflect the evolutionary course of this protein. 4. Tropomyosin from shellfish adductor muscle had the ability to bind to rabbit skeletal muscle troponin and actin. This ability is also considered to be a basic characteristic of tropomyosin which has been conserved during evolution.

Actins↗
PubMed1978

Isolation and localization from chicken gizzard of an inhibitory protein for Mg2+-activated skeletal muscle actomyosin ATPase.

An inhibitory protein for Mg2+-activated actomyosin ATPase from rabbit skeletal muscle was prepared from frozen chicken gizzard and purified by DEAE-Sephadex chromatography and gel filtration. 2. The inhibition by this protein was released by the addition of skeletal muscle troponin C and was independent of gizzard tropomyosin. 3. Localization of the inhibitory protein in gizzard muscle tissue and gizzard thin filaments was demonstrated by immunohistological techniques and immunodiffusion tests.

Actomyosin↗
PubMed1978

Immunohistochemical and ultrastructural distribution of antibodies to troponin-C and troponin-I in normal and dystrophic chicken skeletal muscle.

The pectoral muscles from normal and dystrophic chickens were reacted with rabbit antisera to troponin-C and to troponin-I, and the distribution of antibodies was determined by fluorescence microscopy of antibody-stained myofibrils and immuno-electron microscopy of separated I band segments. Chickens of dystrophic strain 308 and control New Hampshire hens were used in this work. Myofibrils which were prepared from both normal and dystrophic muscles and reacted with anti-troponin-I were fluorescent in the I band and A band regions. The Z lines and H zones were unstained. Myofibrils prepared from normal pectoral muscle and treated with anti-troponin-C yielded a pattern of fluorescence similar to that for anti-troponin-I treated myofibrils. However, those myofibrils isolated from dystrophic muscle and reacted with anti-tropinin-C had a weak fluorescence over their entire lengths, and discrete A- and I-band staining was not visible. These results were confirmed by ultrastructural studies of separated I segments reacted with the antisera. It is concluded that in the dystrophic muscle either the antigenic sites of troponin-C are changed which results in a loss of antibody-combining ability or these sites are masked in some way which prevents the reaction with the antibody.

Animals↗
PubMed1977

An effect of avian hereditary muscular dystrophy on the reaction of troponin-C with its antibody.

Antibody prepared against troponin-C, the calcium binding component of the troponin complex, was reacted with I band segments, and the distribution of antibody binding was assessed by immuno-electron microscopy. The I segments were isolated from glycerinated pectoral muscle which was prepared from normal adult chickens and from dystrophic chickens of strain 308. The antibody was deposited at 384 A +/- 7 A intervals along the thin filaments of the normal muscle. In contrast to the normal controls the dystrophic muscle did not exhibit a distinct periodicity when reacted with anti-troponin-C. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate revealed that although protein bands corresponding to troponin-C could be observed in the gels of the dystrophic preparations, the troponin-C band had migrated slower than that from normal thin filaments. It is concluded that avian muscular dystrophy produces an alteration of the structure of troponin-C resulting in (1) an inability of the protein to combine with its specific antibody and (2) a change in its electrophoretic behavior.

Animals↗
PubMed1977

Distribution of antibodies to the troponin complex, troponin-C and troponin-I in chicken skeletal muscle as determined by a simplified method for immuno-electron microscopy.

Antisera against the troponin complex, troponin-C and troponin-I have been utilized to locate these proteins in normal, adult chicken skeletal muscle and in filaments prepared from chicken acetone dried powder. The antisera had been previously characterized by immunochemical methods and were employed to ascertain the distribution of the proteins by a simple method for immuno-electron microscopy. Glycerinated chicken breast muscle was treated with the antisera, unreacted antibody was washed from the muscle, and a goat anti-rabbit gamma-globulin was added to enhance the electron density of the antigen-antibody complexes. A periodic distribution of anti-troponin-C at a mean interval of 389 A was observed along the thin filaments in the sectioned tissue. Anti-troponin-I was deposited every 399 A (P less than 0-01). Thin filaments were prepared from acetone dried powder and reacted with the antisera. The anti-troponin-C was located every 389 A; anti-troponin-I, every 399 A (P less than 0-01). Our technique for immuno-electron microscopy is compared with that used by others, and the significance of the findings is discussed.

Analysis of Variance↗
PubMed1977

On the heterogeneity and organ specificity of chicken tropomyosins.

1. Tropomyosins from chicken cardiac, skeletal, and gizzard muscles were each resolved into two subunits by polyacrylamide gel electrophoresis in a system containing sodium dodecylsulfate (SDS), urea and sodium borate, and were designated C1 C2, S1 S2, and G1 G2, respectively, in descending order of mobility on electrophoresis. S1, S2, G1, and G2 were prepared as pure samples by electrophoresis. 2. The apparent molecular weights of C (C1 + C2), S1, S2, G1, and G2 were calculated to be 36,000, 36,000, 37,500, 36,000, and 40,000, respectively, based on SDS gel electrophoretic mobility according to the method of Weber and Osborn. C and S1 showed nearly the same mobility in all electrophoretic systems tried. S1 and G1, which comigrated in an SDS-sodium borate system, showed different mobilities upon addition of 5 M urea to the system. 3. Immunological evidence presented indicates that each subunit has a specific antigenic site(s) in addition to an identical one(s) in common with the others. 4. As each tropomyosin subunit formed two precipitin lines with the homologous antiserum, as many as ten kinds of subunits may exist in chicken muscles.

Animals↗
PubMed1976

Membrane-associated phosphatidylglycerophosphate synthetase from Escherichia coli: purification by substrate affinity chromatography on cytidine 5'-diphospho-1,2-diacyl-sn-glycerol sepharose.

The membrane-associated cytidine 5'-diphospho-1,2-diacyl-sn-glycerol (CDP-diglyceride):sn-glycerol-3-phosphate phosphatidyltransferase (EC 2.7.8.5) from Escherichia coli has been solubilized wiTriton X-100 and purified 6000-fold to 85% of homogeneity. The major purification was attained using several modifications of the the CDP-diglyceride Sepharose affinity chromatography system described by Larson et al. (Larson, T.J., Hirabayashi, T., and Dowhan, W. (1976), Biochemistry 15, 974). The native enzyme in Triton X-100 had an apparent molecular weight of over 200 000, as judged by Sepharose 6B gel filtration. The apparent size of the native enzyme appeared to be due to its association with Triton X-100, as judged by sucrose gradient centrifugation, polyacrylamide gel electrophoresis, and the lack of affinity for ion-exchange resins. The minimum subunit molecular weight of the enzyme, determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis, was 24 000. This low molecular weight is consistent with the stability of enzyme to heat, urea, or sodium dodecyl sulfate denaturation. The purified enzyme had an absolute requirement for magnesium ion (KM = 50 mM) and Triton X-100 (0.5-6%) for activity when either CDP-diglyceride or dCDP-diglyceride was used as substrate. Kinetic analysis of the enzymatic reaction indicated an ordered sequential Bi-Bi reaction with the liponucleotide forming a dead-end complex at high concentration, which inhibited both the forward and reverse reactions. The enzyme would not hydrolyze the pyrophosphate bond of its lipid substrate or the phosphate esters of its lipid product but would catalyze a cytidine 5'-monophosphate dependent exchange reaction between glycero-3-phosphate and phosphatidylglycerophosphate.

Chromatography, Affinity↗