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991.
Yuji Kamiya Akira Sakurai Saburo Tamura Nobutaka Takahashi Keiko Abe Eiko Tsuchiya Sakuzo Fukui Chieko Kitada Masahiko Fujino 《Biochemical and biophysical research communications》1978,83(3):1077-1083
Rhodotorucine is a peptidyl factor which induces mating tube formation in . The amino acid sequence of the factor was determined by Edman degradation and enzymatic hydrolysis. Rhodotorucine was shown to contain a lipophilic amino acid, S-farnesyl cysteine, at C-terminus by proton magnetic resonance, mass spectrometry and chemical synthesis. We proposed the following structure for rhodotorucine . H-Tyr-Pro-Glu-Ile-Ser-Trp-Thr-Arg-Asn-Gly-Cys(S-farnesyl)-OH 相似文献
992.
Miki Takuma; Kamiya Yuji; Fukazawa Masanori; Ichikawa Tadashi; Sakurai Akira 《Plant & cell physiology》1990,31(2):201-206
Inhibition of the biosynthesis of gibberellins by 4'-chloro-2'-(a-hydroxybenzyl)-isonicotin-anilide(inabenfide) was investigated with cell-free systems preparedfrom immature seeds of Cucurbita maxima, Phaseolus vulgarisand Pisum sativum. Inabenfide specifically inhibited the oxidationof kaurene, kaurenol and kaurenal but it did not inhibit theoxidation steps that lead to kaurenoic acid. The (S)- and (R)-formsof inabenfide and 2'-benzoyl-4'-chloro-isonicotinanilide (compound[1]) also inhibited the same oxidation steps. The (S)-form wasthe most active in inhibition of the oxidation of kaurene; theracemic form (inabenfide) was one half as effective; and the(R)-form and compound [1] had little effect on the biosynthesisof gibberellins. Growth-retardant activities of these compoundswere also examined using seedlings of C. maxima. Since the growth-retardantactivity of these compounds was correlated with their abilityto inhibit the oxidation of kaurene in cell-free systems, wesuggest that the growth-retardant activity of inabenfide isdue to inhibition of the three oxidation steps from kaureneto kaurenoic acid in the biosynthesis of gibberellins. (Received August 17, 1989; Accepted December 4, 1989) 相似文献
993.
Bovine thymus poly(adenosine diphosphate ribose) polymerase. Physical properties and binding to DNA 总被引:10,自引:0,他引:10
Purified bovine thymus poly(adenosine diphosphate ribose) polymerase is a monomeric protein with a single polypeptide chain having a molecular weight of approximately 130,000, determined by sodium dodecyl sulfate-gel electrophoresis, analytical ultracentrifugation, and gel filtration. A high frictional ratio (1.81) indicated that the molecule has an elongated shape, or a high solvation, or both. The enzyme is a basic protein (pI 9.8), and amino acid analysis showed a relatively high lysine content. The enzyme activity is dependent on double-stranded DNA and is solely correlated with single- or double-stranded breaks on the DNA. Filter binding assay technique showed that the enzyme-activating efficiency of DNA correlated sufficiently with its enzyme-binding efficiency. Thus, a very high enzyme-activating efficiency of a DNA fraction (active DNA) which was separated from the crude enzyme fraction is mainly due to its high enzyme-binding efficiency. It was also shown that single-stranded DNA and heparin had a strong inhibitory effect on the binding of the enzyme to double-stranded DNA, whereas competitive inhibitors did not affect the binding, We interpret these results to indicate that the binding of the enzyme to double-stranded DNA is a prerequisite step to its catalytic activity and has a dual function: (a) to position the enzyme on specific binding sites such as single- or double-stranded breaks on the DNA, and (b) to induce an active conformation of the enzyme. 相似文献
994.
Blue light-induced formation of phosphoenolpyruvate carboxylase in colorless Chlorella mutant cells 总被引:1,自引:0,他引:1
The activities of NAD-malic dehydrogenase, aspartate aminotransferase,phosphoenolpyruvate carboxylase and NADP-malic enzyme in colorlessmutant cells of Chlorella vulgaris (Mutant No. 125) decreasedduring starvation (in phosphate buffer in darkness). The mostpronounced decrease was observed in phosphoenolpyruvate carboxylaseactivity. A trace of ribulose diphosphate carboxylase activitydetected in the growing cells disappeared on starvation andno activity of pyruvate carboxylase was detected in these mutantcells. Blue light (462 or 465 nm) enhanced phosphoenolpyruvatecarboxylase activity in the starved cells about 2-fold, whilethe activities of aspartate aminotransferase and NADP-malicenzyme were slightly lowered by the blue light. Red light (mainly600650 nm) brought about a slight decrease in all theenzyme activities tested. Cycloheximide (5 µ/ml) completelyabolished the enhancing effect of blue light on phosphoenolpyruvatecarboxylase activity, indicating that the short wavelength lightspecifically increased the de novo synthesis of this enzyme. (Received March 14, 1975; ) 相似文献
995.
996.
997.
Sadafumi Noda Noriho Kamiya Masahiro Goto Fumiyuki Nakashio 《Biotechnology letters》1997,19(4):307-310
Structural ring-opening of lactones driven by enzymatic polymerization has been performed using low concentration dosages of surfactant-coated lipases in organic media. By comparison, enzymatic polymerization rate with coated lipase proceeded at a rate 100-fold better than native powder. Similarly a higher polymeric molecular weight (21,300), narrow dispersity (Mw/Mn=1.9) and better conversion (100%) were obtained following polyesterification tests with surfactant-coated lipase. 相似文献
998.
Naifeh K. H.; Severinghaus J. W.; Kamiya J.; Krafft M. 《Journal of applied physiology》1989,66(4):1956-1964
By recording only inspired PCO2 (PICO2) in a hood and transcutaneous PCO2 (PsCO2) the Hazinski method was used to estimate nonintrusively the slope (Sr) per Torr PsCO2 of the fractional ventilatory response to approximately 18 and 30 Torr PICO2 in 17 healthy elderly subjects (10 women) and 17 younger controls (9 women) during wakefulness, slow-wave sleep (SWS), and rapid-eye-movement (REM) sleep. Eight of the older subjects had sleep disturbance indexes (RDI) greater than 5. Sr fell with SWS from 0.90 +/- 0.34 to 0.60 +/- 0.29 (P less than 0.006) in the younger group (n = 16) but in the older subjects was 0.60 +/- 0.27 awake and 0.58 +/- 0.34 (NS) asleep (n = 15). The changes from awake to REM in subsets of 9 younger and 10 older subjects who successfully completed REM tests were from 0.95 +/- 0.32 to 0.70 +/- 0.38 (P less than 0.03) and 0.53 +/- 0.31 to 0.57 +/- 0.25 (NS), respectively. We conclude that the increased incidence of respiratory disturbance during sleep in these older subjects cannot be attributed to greater sleep-induced reduction of CO2 sensitivity. 相似文献
999.
Although several authors have presented dark-field micrographs of axonemes or of outer doublet microtubules from sperm tails, singlet microtubules have not been observed individually by light microscopy. This study demonstrates the technical possibility of observing individual microtubules by dark-field microscopy. While polymerized brain microtubules were always observed to be straight, the outer doublet microtubules from sperm tails assumed a coiled form, as demonstrated by Summers & Gibbons [1] and Zobel [2]. The coiled conformation of the outer doublets was found to be a left-handed helix, with a nearly uniform diameter. 相似文献
1000.
Using two species ofSpirogyra and one species ofZygnema, it was demonstrated on a quantitative basis that these algal filaments grow while twisting around their own axis. The sense
of spiral growth of the cell wall inSpirogyra-1 was always left-handed being coincident with the sense of chloroplast helix. InSpirogyra-2, the growth vector of the cell wall was likewise left-handed in most cases, but there occurred right-handed growth also.
InZygnema both left-handed and right-handed senses of spiral growth were found in nearly equal frequencies. Besides the natural cell
wall growth, the effects of longitudinal tension and turgor pressure on elongation and twisting of the filaments were briefly
studied. It was shown that the cell wall of Zygnemataceae exhibited mechanical anisotropy in helical direction. 相似文献