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71.
Nine representative pairs of heterothallic (=self-sterile, cross-fertile) strains of theClosterium peracerosum-strigosum-littorale complex from the northern Kanto area in Japan have been studied under the defined standard culture conditions. Since a wall
thickening at cell apices was observed in vegetative cells of all the strains, these strains turned out to belong to the morphological
group II (Ichimura and Watanabe, 1976). The result of statistical analyses of their cell size variations corresponded well
with the result of intercrossing experiments between them. It was shown that these strains are virtually composed of three
biologically different groups which are morphologically distinct and reproductively isolated completely or at least partially
from each other. For convenience, these three groups have been designated as II-A, II-B, and II-C in the order of from smaller
to larger cell size. In intra-group crossings, a large number of zygospores were formed, and they germinated well to yield
healthy populations of their progenies in all the three groups. In inter-group crossings, no sign of sexual reproduction was
observed between Group II-A and Group II-C or Group II-B and Group II-C, and a marked decrease of zygospore formation was
observed between Group II-A and Group II-B, especially between Group II-A minus and Group II-B plus. It was concluded that
the distinctions between the three groups are biologically sound and that each represents an evolutionary unit.
This paper represents a portion of a thesis submitted to the faculty of the Graduate School of Hokkaido University by the
senior author in partial fulfillment of the requirements for the degree of Doctor of Science.
This study was supported by the Grants in Aid, No. 174233 & No. 034036, from the Scientic Research Fund of the Ministry of
Education, Japan. 相似文献
72.
Hana Dolezalova Matej Stepita-Klauco Jan Kucera Hideyuki Uchimura Makoto Hirano 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1978,146(1):67-76
Concentrations of cadaverine, monoacetylcadaverine and monopropionylcadaverine in the blood of schizophrenic and nonschizophrenic subjects were measured. Two groups, one from the U.S.A. the other from Japan, were tested. Monoacetylcadaverine and monopropionylcadaverine were found elevated in the blood of some schizophrenic patients in comparison with those in controls in each group. Their increase could be caused by a reduced monoamine oxidase activity or by an increased acylation in schizophrenic patients. 相似文献
73.
When thiamine concentration in subculture medium was rapidlylowered to nil, soybean cells in suspension became necroticand stopped growing entirely. When it was gradually lowered,cell growth was vigorous until the concentration was reducedto 7.8?103 mg/liter. The cells at this level of thiamineceased growing for a time, but prolonged culture in the samemedium resulted in the appearance of fresh white cells whichcould be easily distinguished from the old brown, necrotic cellsin the aggregates. These new cell lines could be subculturedwith further reduction in the thiamine supply, growing as largeraggregates of about 4 mm in diameter. New cell lines were similarly obtained by prolonged culturesin media containing a thiamine precursor; three lines appearedto be habituated to the pyrimidine moiety and one to the thiazolemoiety. The latter cell line could be subcultured without thiamineand its precursors for at least eight passages. These habituatedcells were characterized by the increase of the dry to freshweight ratio and by their growth in large aggregates.
1Present address: Section of Phytochemical Research, Eisai Co.,Ltd., Kawashima, Gifu 483, Japan. (Received December 15, 1978; ) 相似文献
74.
Hydrolyses of N-trans-cinnamoylimidazole (1) and N-acetylimidazole (2) were accelerated by cyclohexaamylose (α-CA) and cycloheptaamylose (β-CA) at 25°C. The cleavage of the amide bond in 1 at pH 9.0 was accelerated by α-CA and β-CA by 28- and 38-fold, respectively, whereas the cleavage of the amide bond in 2 at pH 7.0 was accelerated by α-CA and β-CA by 50- and 28-fold, respectively. The β-CA-accelerated hydrolysis of 1 proceeded via binding, acylation of β-CA, and deacylation of β-CA trans-cinnamate, which is consistent with the pathway used by serine proteases. The deuterium oxide solvent isotope effects for acylation and deacylation steps indicate nucleophilic attack in acylation and general basic attack in deacylation. The present finding of the acceleration by cycloamyloses in the cleavages of amide bonds in 1 and 2 indicates that cycloamyloses are an excellent model for hydrolytic enzymes. 相似文献
75.
(+)-Abscisic acid was isolated as the methyl ester from Pinus densiflora pollen and identified spectroscopically. 相似文献
76.
Solvent-extractable lipids in Pinus densiflora pollen were investigated. The cis- and trans-isomers of 1,16-dioxo-, 1-hydroxy-16-oxo- and 1, 16-dihydroxyhexadecan-7-yl p-coumarates were identified. 相似文献
77.
A sulfite-dependent ATPase [EC 3.6.1.3
[EC]
] of Thiobacillus thiooxidanswas activated and solubilized by treatment with trypsin [EC3.4.4.4
[EC]
], and purified 84-fold with a 32% recovery. It requiredboth Mg2+ and SO32 for full activity, and its optimumpH was found at 7.58.0. Mn2+, Co2+, and Ca2+ could partiallysubstitute for Mg2+, while SeO32 and CrO42 couldpartially substitute for SO32. The enzyme hydrolyzed ATP and deoxy-ATP most rapidly and otherphosphate esters were poorer substrates. The apparent Km valuefor ATP was 0.33 mM. The enzyme activity was strongly inhibitedby 0.2 mM NaN3 and 10 mM NaF. (Received July 27, 1977; ) 相似文献
78.
Methyl 4,6-O-benzylidene-2-deoxy-α-D-ribo-hexopyranoside (1) is converted into methyl 3,4-di-O-benzoyl-6-bromo-2,6-dideoxy-α-D-ribo-hexopyranoside (3) via the 3-O-benzoyl derivative (2) of 1 by subsequent treatment with N-bromosuccinimide. Compound 3 is the key intermediate in high-yielding, preparative syntheses of the title dideoxy sugars, which are constituents of many antibiotics. Dehydrohalogenation of 3 affords the 5,6-unsaturated glycoside 7. which undergoes stereospecific reduction by hydrogen with net inversion at C-5 to give methyl 3,4-di-O-benzoyl-2,6-dideoxy-β-L-lyxo-hexopyranoside (8), whereas reductive dehalogenation of 3 provides the corresponding D-ribo derivative 4. The unprotected glycosides 9 (L-lyxo) and 5 (D-ribo) are readily obtained by catalytic transesterification, and mild, acid hydrolysis gives the crystalline title sugars 10 (L-lyxo) and 6 (D-ribo) in 45 and 57% overall yield from 1 without the necessity of chromatographic purification at any of the steps. 相似文献
79.
The chemical synthesis of two new glycerophosphatide analogues containing steroid groups, i.e., 1,2-dipalmitoyl-rac-glyceryl-3-phosphoryl-3′β-cholesterol and 1,2-dipalmitoyl-rac-glyceryl-3-phosphoryl-20′-(3β-hydroxy norpregn-5-ene) is described. 相似文献
80.
Subcutaneous infection withYersinia enterocolitica harboring plasmid responsible for Ca2+ dependence at 37°C induced cell-mediated protective immunity against a lethal challenge withYersinia pestis; the isogenic derivative strain cured from this plasmid subverted the immunity in mice. This is the first identification of the antigen(s) responsible for the induction of cell-mediated protective immunity against the facultatively intracellular bacteria. 相似文献