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91.
Tetsuo Omata Noritada Iwamoto Tomio Kimura Atsuo Tanaka Saburo Fukui 《Applied microbiology and biotechnology》1981,11(4):199-204
Summary
dl-Menthyl succinate was successfully hydrolyzed stereoselectively by Rhodotorula minuta var. texensis cells entrapped within photo-crosslinked or polyurethane resin gels in water-saturated n-heptane. The hydrolyzed product was found to be pure l-menthol. The catalytic activity of the immobilized cells, especially those entrapped in urethane polymers, was far more stable than that of the free cells. The half-life of the polyurethaneentrapped cells was estimated to be 55–63 days in the organic solvent.Dedicated to the 65th birthday od Professor Dr. G. Manecke 相似文献
92.
Polynucleotides. L. Synthesis and properties of poly (2''-chloro-2''-deoxyadenylic acid) and poly (2''-bromo-2''-deoxyadenylic acid). 总被引:4,自引:4,他引:0
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Poly (2'-chloro-2'-deoxyadenylic acid) and poly (2'-bromo-2'-deoxyadenylic acid) were synthesized from the corresponding diphosphates with the aid of polynucleotide phosphorylase from E. coli. UV, CD, acid titration and mixing with poly (U) were investigated. Comparing these properties with those of poly (A) and poly (2'-azido-2'-deoxyadenylic acid), it was found that 2'substituents exert significant effects on the thermal stability of these polynucleotides, though the overall conformational structure was not greatly changed. 相似文献
93.
Takayoshi Shotake Yoshiko Ohkura Goichi Ishimoto 《Primates; journal of primatology》1977,18(2):285-290
The electrophoretic variations of erythrocyte phosphohexose isomerase (PHI) were examined in 1433 blood samples from 37 troops
of Japanese macaques in order to clarify the gene dynamics of this species. The genetic polymorphisms were observed in several
troops. The troops showing the variation of PHI were Fukushima, Shiga A, Shiga C, Ryozenyama, Mikata I and II, Kawara, Takasakiyama
A, B, and C, Itsuki, Koshima and Kushima. The variant alleles found in these troops were PHI
2
mac
, PHI
7
mac
, PHI
8
mac
, and PHI
10
mac
alleles, and the PHI
10
mac
allele was newly found in the present work. 相似文献
94.
The chemical and catalytic properties of potato phosphoglucomutase [EC 2.7.5.1] were studied using various enzyme species (Peaks Ia, Ib, Ic, and II; Takamiya, S. & Fukui, T. (1978) Plant Cell Physiol. 19, 319--328). The molecular weights of the species are all approximately 60,000. No indication of the presence of subunit structure was obtained under various conditions. The amino acid composition of Peak Ia is generally similar to those of the enzymes from other sources, though it has some peculiarities. The Peak Ia and Peak II enzymes both absolutely require alpha-D-glucose 1,6-bisphosphate and Mg2+ for activity, and appear to have a "ping-pong" mechanism. A low concentration of Be2+ inhibits their action, the inhibition being retarded either by Mg2 or EDTA. Although the inhibition patterns by various metabolites, are similar for Peaks Ia and II, they differ in their kinetic parameters and optimal pH values. 相似文献
95.
The amounts of d-alanine derivatives, γ-l-glutamyl-d-alanine and N-malonyl-d-alanine, increase rapidly during the early growth of pea seeds. Pyruvate-[1?14C], l-alanine-[U?14C], d-alanine-[U?14C], l-alanine-[15N] and 15NH4Cl were therefore fed to the seedlings and the incorporation investigated. Labelling results revealed that pea seedlings can utilize these erogenous compounds to form d-alanine and that labelled l-alanine is effectively converted to the d-enantiomer with retention of 14C and, largely, 15N label. Enzyme analyses in vitro provided additional evidence that the extract of pea seedlings catalyzes the direct conversion of l-alanine to d-alanine. The data suggest that the de novo synthesis of d-alanine in pea seedlings occurs by a racemase reaction. 相似文献
96.
Elevation of nucleotide pyrophosphatase activity in skin fibroblasts from patients with Lowe's syndrome 总被引:3,自引:0,他引:3
H Yoshida S Fukui I Yamashina T Tanaka T Sakano T Usui T Shimotsuji H Yabuuchi M Owada T Kitagawa 《Biochemical and biophysical research communications》1982,107(3):1144-1150
Undersulfation observed in the glycosaminoglycans synthesized by cultured skin fibroblasts from a Lowe's syndrome patient[Fukui, S. etal. (1981) J. Biol. Chem. 256, 10313–10318] was found to be caused by elevated degradation of 3′-phosphoadenosine 5′-phosphosulfate (PAPS). The enzyme involved in this degradation was then identified as an enzyme of nucleotide pyrophosphatase (EC 3.6.1.9) nature, cleaving the phosphosulfate linkage. The specific activities were 8 – 24 (mU/mg protein) in patients' fibroblasts, in contrast to 3 in normal and 5 – 14 in heterozygote cells. A possibility is discussed that the elevation of nucleotide pyrophosphatase activity is the primary genetic defect in Lowe's syndrome. 相似文献
97.
Y Fukui K Sawai M Furudate N Sato Y Iwazumi K Ohsaki 《Molecular reproduction and development》1992,33(3):357-362
The present study was conducted to investigate the effects of different culture durations (24-36 hr) on bovine oocyte maturation in vitro and the effect of the presence or absence of cumulus cells at the time of treatment to induce parthenogenetic activation (exposure to ethanol and cytochalasin B; CB) (experiment I). The effects of dosage (2.5 or 5.0 micrograms/ml) and incubation time (2.5, 5, or 10 hr) in CB (experiment II) on the subsequent development to the blastocyst stage in vitro was also investigated. In experiment I, cleavage and development to the blastocyst stage were not affected by the presence or absence of cumulus cells at the time of parthenogenetic activation. However, the 24-hr culture duration for in vitro maturation had a significantly lower rate of development to the blastocyst stage than the longer culture durations (27-36 hr). In experiment II, treatment with 5 micrograms/ml CB for 5 hr showed the highest percentage of development to blastocyst in the oocytes matured for both 27 and 30 hr. To determine the viability of the parthenogenetic embryos (morulae and blastocysts), four recipient heifers received two embryos each, and one heifer was found to be pregnant on day 35 following transfer. Although fetal heartbeat was not observed, the subsequent estrus was prolonged in all heifers. The present results demonstrate development of in vitro-matured, parthenogenetically activated bovine embryos up to the preimplantation stage. 相似文献
98.
Preparation of soluble murine IL-6 receptor and anti-murine IL-6 receptor antibodies 总被引:8,自引:0,他引:8
T Saito K Yasukawa H Suzuki K Futatsugi T Fukunaga C Yokomizo Y Koishihara H Fukui Y Ohsugi H Yawata 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(1):168-173
Starting with a previously isolated cDNA clone encoding murine IL-6R, a stable transformed Chinese hamster ovary cell line constitutively expressing soluble murine IL-6R (smIL-6R) has been established. The smIL-6R was purified to homogeneity by sequential filtration and chromatography of culture medium. The smIL-6R augmented the sensitivity of M1 cells to IL-6 in their growth inhibition in a dose-response manner. Rat hybridomas producing mAb specific to murine IL-6R were also established. One of the clones, RS13, produced IgG2a isotype that was capable of inhibiting IL-6 activity. ELISA for the quantitation of smIL-6R was established, which could detect smIL-6R in a quantity as low as 1 ng/ml. 相似文献
99.
Yukio Fukui Kenji Gushima Shunpei Kakuda Hiroaki Hashimoto 《Ichthyological Research》1991,37(4):395-401
Coloration and sex change were studied in a temperate wrasseHalichoeres poecilopterus in the central part of the Seto Inland Sea, Japan. 1,270 examples, 45–179 mm SL, were collected from May to December both
in 1983 and 1984. The species is a diandric, protogynous hermaphrodite, and has three color patterns: pale color type (A),
brilliant color type (B) and intermediate color type (AB). A-fish were less than 142 mm SL and consisted of primary males
(42.6%), females (55.4%), secondary males (0.3%) and fish with transitional gonads (1.7%). A-females changed their color to
B, through AB, in the size range 101–131 mm SL. A-primary males changed their color to B, through AB, in the size range 103–134
mm SL. B-fish consisted of primary males (38.6%), secondary males (54.6%) and fish with transitional gonads (6.8%). The majority
of females changed their sex to male in the size range 98–131 mm SL. 相似文献
100.
At present, the concept of plasmatic imbibition is generally accepted. That is, observation of weight change or pigmentation methods of the grafts were established to support it. In the present study, we investigated plasmatic imbibition in rat musculocutaneous grafts histologically using peroxidase, which is one of the reductases. Tissue pigmentation by peroxidase became an insoluble sediment that indicated the sites of peroxidase activity. The entire contact surface of the graft with the recipient bed was stained brown within a few minutes after the operation. At 30 minutes, the panniculus carnosus and dermis were stained dark brown diffusely, extending toward the epidermis. This condition continued until the sixth day at least. As a result, peroxidase that was dissolved with the exudate between the graft and recipient bed was imbibed into the musculocutaneous graft. 相似文献