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891.
The fission yeast pmk1+ gene encodes a novel mitogen-activated protein kinase homolog which regulates cell integrity and functions coordinately with the protein kinase C pathway. 总被引:4,自引:1,他引:3 下载免费PDF全文
T Toda S Dhut G Superti-Furga Y Gotoh E Nishida R Sugiura T Kuno 《Molecular and cellular biology》1996,16(12):6752-6764
We have isolated a gene, pmk1+, a third mitogen-activated protein kinase (MAPK) gene homolog from the fission yeast Schizosaccharomyces pombe. The predicted amino acid sequence shows the most homology (63 to 65% identity) to those of budding yeast Saccharomyces Mpk1 and Candida Mkc1. The Pmk1 protein contains phosphorylated tyrosines, and the level of tyrosine phosphorylation was increased in the dsp1 mutant which lacks an attenuating phosphatase for Pmk1. The level of tyrosine phosphorylation appears constant during hypotonic or heat shock treatment. The cells with pmk1 deleted (delta pmk1) are viable but show various defective phenotypes, including cell wall weakness, abnormal cell shape, a cytokinesis defect, and altered sensitivities to cations, such as hypersensitivity to potassium and resistance to sodium. Consistent with a high degree of conservation of amino acid sequence, multicopy plasmids containing the MPK1 gene rescued the defective phenotypes of the delta pmk1 mutant. The frog MAPK gene also suppressed the pmk1 disruptant. The results of genetic analysis indicated that Pmk1 lies on a novel MAPK pathway which does not overlap functionally with the other two MAPK pathways, the Spk1-dependent mating signal pathway and Sty1/Spc1/Phh1-dependent stress-sensing pathway. In Saccharomyces cerevisiae, Mpk1 is involved in cell wall integrity and functions downstream of the protein kinase C homolog. In contrast, in S. pombe, Pmk1 may not act in a linear manner with respect to fission yeast protein kinase C homologs. Interestingly, however, these two pathways are not independent; instead, they regulate cell integrity in a coordinate manner. 相似文献
892.
Toshiro Matsunaga Akira Okubo Motohiro Fukami Sunao Yamazaki Shozo Toda 《Biochemical and biophysical research communications》1981,102(1):524-530
Polysaccharides, which come into resonances in the 13C NMR spectrum of intact mycelium and give anomeric carbon signals at 107.5 and 108.3 ppm, are associated with the cell wall. By 13C NMR and gas liquid chromatography analysis, it is shown that the polysaccharides are two types of β-galactofuranosyl residues, one of which has (1→2)-β-galactofuranosyl linkages. Both β-galactofuranosyl residues, which are minor cell wall components, experience rapid internal motion in the cell wall. 相似文献
893.
High ethanol productivities were obtained by cell recycle cultures of yeast and bacterial strains at a dry cell concentration of 200 kg cells m–3 using a new membrane bioreactor system. The filtration rates of the cultures were stabilized by removing the microbial cake on the filter with periodic back flows of the fermentation gas through the filter. For instance, the filtration flux of 0.023 m3m–2h–1 was maintained for 30 h with the periodic cleaning of the filter, whereas it decreased at a half time of 2 h without the cleaning. Ethanol productivity, ethanol concentration and filtration flux attained were: 68.7 kg/(m3 · h), 62.7 kg/m3 and 0.029 m3m–2h–1 for Saccharomyces carlsbergensis, LAM1068, the respective values for Zymomonas mobilis, ZM4, were: 93.7, 33 5 and 0.074. 相似文献
894.
895.
The overall distribution of substance P (SP) immunoreactive (IR) nerves surrounding the cerebral arteries of the bent-winged bat were investigated immunohistochemically. In this microchiropteran species, the walls from the vertebral artery to the caudal part of the basilar artery have considerably well-developed plexuses of SP-IR nerves, whereas no demonstrable SP-IR fibers were found in the rostral part of the basilar artery, and in more rostrally located arteries the nerve supply was very sparse or occasionally lacking. This innervation pattern has not yet been established for the cerebral arterial systems of other mammals that have been studied under normal conditions, but it is very similar to the pattern of SP-IR innervation observed in the guinea pig and cat of which the trigeminal ganglia have been destroyed. From the combination of this and other immunohistochemical findings, it is suggested that SP-IR nerves innervating the vertebral and basilar arteries of the bent-winged bat originate from the upper cervical dorsal root ganglia (DRG) and enter the cranial cavity along the vertebral artery and through the meninges. 相似文献
896.
Ishizuka Shintaro Toda Kazuya Furuichi Takeshi 《International journal of primatology》2020,41(2):401-414
International Journal of Primatology - Relationships between females of different groups in female philopatric species are typically antagonistic, whereas those in female dispersing species can be... 相似文献
897.
Elastase has been reported to have a multiplicity of activities which may be protective against atherosclerosis. The data reported here support those reports and show a clear antiatherosclerotic effect in hyperlipidemic chickens. We have shown here that a reduction in calcium and lipid accumulation in aortic tissue and possibly a plasma cholesterol lowering effect can be seen in the chicken when treated with elastase. The most important effect in this animal is probably to aid removal of lipid bound to elastin in the intima. This was achieved at a dose of only 600 U elastase while reductions in tissue calcium required 1800 U elastase. 相似文献
898.
The bactericidal activity of tea and coffee 总被引:10,自引:4,他引:6
Masako Toda Sachie Okubo Reiko Hiyoshi Tadakatsu Shimamura 《Letters in applied microbiology》1989,8(4):123-125
Extracts of black tea, green tea, pu-erh tea or coffee inhibited the growth of various bacteria known to cause diarrhoeal diseases. Tea or coffee also showed bactericidal activity against Staphylococcus aureus and Vibrio parahaemolyticus. 相似文献
899.
900.
K. Toda 《Biotechnology and bioengineering》1976,18(8):1117-1124
In a previous study on the chemostat culture of Saccharomyces carlsbergensis, maximum invertase specific activity was observed at an intermediate dilution rate. A possible regulation mechanism, assuming there are simultaneous effects of induction and repression on two sites of the operator loci for invertase formation, is proposed which might account for the observed curve of the dilution rate effect. 相似文献