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Crosses between genotypically distinct thalli of the monoecious species Porphyra yezoensis were carried out using immature thallus fragments from green- and red-type color mutants and also wild-type thalli. As the genes governing the mutants are monogenic, recessive to the wild-type, and belong to the same linkage group, the degree of self-fertilization could be estimated based on the pigmentation of the resultant diploid conchocelis. The degree of self-fertilization in the cross between the green-type and the wild-type was 48.5–55.0%, and in the cross between the red-type and the wild-type was 45.1–56.5%. In the cross between the green- and red-type mutants, the degree of self-fertilization was 46.0–54.5% when the green-type was the female parent, and was 44.8–55.6% when the red-type was the female parent. 相似文献
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The improved methods for the preparation of valency hybrid hemoglobins, (α3+β2+)2 and (α2+β3+)2 were presented. The (α3+β2+)2 valency hybrid was separated from the solutions of partially reduced methemoglobin with ascorbic acid, by using CM 32 column chromatography. The (α2+β3+)2 valency hybrid was also isolated from hemoglobin solutions, which were partially oxidized with ferricyanide, by chromatography on CM 32 column. These valency hybrid hemoglobins were found to be single on isoelectric focusing electrophoresis. Present procedures are very simple and are suitable for the bulk preparation of (α3+β2+)2 and (α2+β3+)2 valency hybrids. 相似文献
77.
Effects of Phosphate in Medium on Protein Secretion in a Protein-Producing Bacterium, Bacillus brevis 47 总被引:2,自引:0,他引:2
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Norihiro Tsukagoshi Hidehiko Yamada Akio Tsuboi Shigezo Udaka 《Applied microbiology》1981,42(2):370-374
Bacillus brevis 47 secreted up to 1 mg of protein per ml in a chemically defined medium, depending on phosphate concentration. The composition of exoproteins was altered quantitatively by the concentration of external phosphate. Morphologically, B. brevis 47 showed a distinct three-layered cell wall structure and shed the outer two layers during growth. 相似文献
78.
Summary A method for the preparation of ultrathin sections of metaphase chromosomes is described. This method was applied to human metaphase chromosomes, which were immunocytochemically stained with anti-DNA and anti-ribonucleoprotein antibodies, derived from patients with auto-immune disease. Conventionally prepared metaphase spreads as well as cytocentrifuge preparations of chromosome suspensions were studied. The results indicate that the ultrastructure of chromosomes and the immunoreactivity of chromosomal constituents are influenced by the applied preparation methods. In comparison with whole mount preparations, ultrathin sections of immunostained chromosomes allow higher resolution and more precise localization of immunoreactive sites within the chromosomal structure. 相似文献
79.
Akio Ito Shin-ichi Hayashi Touho Yoshida 《Biochemical and biophysical research communications》1981,101(2):591-598
The participation of a cytochrome b5-like hemoprotein of outer mitochondrial membrane (OM cytochrome b) in the NADH-semidehydroascorbate (SDA) reductase activity of rat liver was studied. NADH-SDA reductase activity was strongly inhibited by antibodies against OM cytochrome b and NADH-cytochrome b5 reductase, whereas no inhibition was caused by anti-cytochrome b5 antibody. NADH-SDA reductase exhibited the same distribution pattern as OM cytochrome b-mediated rotenone-insensitive NADH-cytochrome c reductase activity among various subcellular fractions and submitochondrial fractions. Both activities were localized in outer mitochondrial membrane. These observations suggest that OM cytochrome b-mediated rotenone-insensitive NADH-cytochrome c reductase system participates in the NADH-SDA reductase activity of rat liver. 相似文献
80.
Izumi Nakashima Fumihiko Nagase Akio Matsuura Takashi Yokochi Nobuo Kato 《Cellular immunology》1980,52(2):429-437
We demonstrated that each of various polyclonal lymphocyte activators (PLA) exhibits two types of adjuvant action to initiate the carrier-specific helper T-cell response to otherwise nonimmunogenic antigen. Type 1 action was characterized as that to initiate the T-cell response to subcutaneous injection of soluble bovine γ-globulin (BGG), and type 2 as that to initiate the response to intravenous injection of aggregated BGG. Each of various PLA showed these two types of adjuvant action in a dissociated fashion. The capsular polysaccharide of Klebsiella pneumoniae (CPS-K) showed both types of action to the highest degrees. Lipopolysaccharide of Escherichia coli exhibited type 2 action as markedly as CPS-K, but failed to show type 1 action. Concanavalin A showed definite type 1 action, but not type 2 action. Polyadenylic-uridylic acid showed definite type 2 action, but not type 1 action. Type 1 and type 2 actions of dextran sulfate were minimal. A hypothetical view is presented to consider that type 1 adjuvant action is directed to two mutually independent sites whereas type 2 action is directed to one site. 相似文献