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991.
992.
993.
Properties of the Dicyclohexylcarbodiimide-Binding Subunit of Cytochrome c Oxidase from Sweet Potato
Nakagawa Tsuyoshi; Maeshima Masayoshi; Muto Hideyo; Asahi Tadashi 《Plant & cell physiology》1992,33(4):489-491
Subunit IV of cytochrome c oxidase from sweet potato was boundwith dicyclohexylcarbodiimide and synthesized in isolated mitochondria.Thus, this subunit corresponds to subunit HI of the analogousmammalian and fungal enzymes. Subunit IV was a mixture of twopolypeptides (subunits IVa and IVb) which differed slightlyin structure.
1Present address: Research Institute of Molecular Genetics,Shimane University, Matsue, 690 Japan.
2Present address: Institute of Low Temperature Science, HokkaidoUniversity, Sapporo, 060 Japan. 相似文献
994.
Mi Hualing; Endo Tsuyoshi; Schreiber Ulrich; Ogawa Teruo; Asada Kozi 《Plant & cell physiology》1994,35(2):163-173
Electron donation to P700+ through plastoquinone in the intersystemchain from both respiratory substrates and the photoreductantsin PSI has been shown to be mediated by the NAD(P)H-dehydrogenasecomplex (NDH) in Synechocystis PCC 6803 cells [Mi et al. (1992)Plant Cell Physiol. 33: 1233]. To confirm the participationof NDH in the cyclic electron flow around PSI, the redox kineticsof P700 and Chi fluorescence were analyzed in cells rendereddeficient in respiratory substrates by dark starvation and inspheroplasts. Dark-starved cells showed a high steady-state level of P700+under far-red (FR) illumination and the plastoquinone pool wasin a highly oxidized state. An NDH-defective mutant consistentlyshowed a high level of P700 oxidation under FR before and afterthe dark starvation. Donation of electrons either from exogenousNADPH or from photoreduced NADPH+ to the intersystem chain viaplastoquinone was demonstrated using spheroplasts from wild-typecells, but not those from the NDH-defective mutant, as monitoredby following changes in the kinetics of Chi fluorescence andthe redox state of P700. The electron flow to PSI via plastoquinone,mediated by NADPH, was sensitive to rotenone, Hg2+ ions and2-thenoyltrifluoroacetone, inhibitors of mitochondrial NDH andsuccinate dehydrogenase, but not to antimycin A. The pool sizeof electrons that can be donated to P700+ from the cytosol throughthe intersystem chain increased with increasing duration ofillumination time by actinic light and was sensitive to rotenonein both wild-type cells and spheroplasts, but no such resultswere obtained in the NDH-defective mutant of Synechocystis 6803.The results support our previous conclusion that NDH is a mediatorof both respiratory electron flow and cyclic electron flow aroundPSI to the intersystem chain in the cyanobacterium Synechocystis. (Received August 20, 1993; Accepted November 22, 1993) 相似文献
995.
Naoto Rikitomi Tsuyoshi Nagatake Tasuku Sakamoto Keizo Matsumoto 《Microbiology and immunology》1994,38(8):607-614
The mechanism of nosocomial respiratory infections caused by MRSA (methicillin-resistant Staphylococcus aureus) in geriatric patients was investigated. Seriously ill patients (SIP) undergoing naso-gastric tube feeding or intravenous hyperalimentation and moderately ill patients (MIP) who were orally fed, were examined for their colonization and infection by Staphylococcus aureus (S. aureus) in the respiratory tract. Colonization of MRSA in the upper respiratory tract in SIP was from six to ten times higher than that in MIP and was associated with a high incidence of MRSA pulmonary infections. In vitro S. aureus adherence to nasal or oropharyngeal cells demonstrated that bacteria binding to nasal cells was higher, which probably can be interpreted as an elevated occurrence of S. aureus colonization in the nasal cavity than in the throat. The binding activity of MRSA was not superior to that of MSSA (methicillin-sensitive S. aureus). Though MRSA binding to the nasal cells from SIP was not higher than those from MIP, MRSA colonization in the upper respiratory tract was more frequently seen in SIP (P < 0.01). A higher incidence of total infectious episodes (P < 0.02-0.001) and more frequent use of antibiotics (P < 0.02-0.001), which were potent against MSSA might be the basis for selection of MRSA in these patients. In fact, the rate of MRSA colonization on the skin (pressure sores) was also higher in SIP (P < 0.01). A low nutritional state in SIP (P < 0.01-0.02) might also be associated with MRSA colonization. The present results indicate that the high frequency of infections, antibiotic administration, MRSA skin colonization and low nutritional condition, are enhancing factors of MRSA acquisition in the respiratory tract for SIP undergoing artificial feeding, in a geriatric hospital. 相似文献
996.
Kamruddin Ahmed Hironori Masaki Iran Cong Dai Akitoyo Ichinose Yoshiaki Utsunomiya Misao Tao Tsuyoshi Nagatake Keizo Matsumoto 《Microbiology and immunology》1994,38(10):767-771
Sputum during the acute exacerbation of chronic respiratory diseases were observed under the electron microscope, to determine the in vivo expression of surface structures of Branhamella catarrhalis (B. catarrhalis), the polymorphonuclear neutrophil (PMN) response to B. catarrhalis infections, and the composition of sputum. It was found that during infection fimbriae are expressed in B. catarrhalis. However, there were sparsely to densely fimbriated bacteria in each sputum sample. The length of the fimbriae were from 50 to 76 nm. In the sparsely fimbriated B. catarrhalis, external to the cell wall, a thin, granular, electron-dense layer was observed. Due to the presence of fimbriae, this layer was not seen in densely fimbriated B. catarrhalis. Blebs were also found in B. catarrhalis. PMNs were found to phagocytose both B. catarrhalis and debris. Evidence was found that debris were formed mainly by the destruction of PMNs. Bacteria as well as debris were phagocytosed by PMNs. 相似文献
997.
We studied the monkeys inhabiting Bacan Island on the Maluku Archipelago, Indonesia. We compared them morphologically with
Sulawesi black macaques (Macaca nigra).We also assessed their distribution on the island and on neighboring islands and the influence of human activity on them.
We found that the Bacan black macaques are essentially similar to Sulawesi macaques; the variations in each locality are comparable.
The monkeys probably inhabit the whole island or, at least, the lower forest thereon. Human activities — cultivation, logging,
catching and killing monkeys — have not much affected their population. Thus they constitute a good stock of Macaca nigra,though the main population in Sulawesi is endangered. 相似文献
998.
A new species,Stromatinia cryptomeriae, is described based on a specimen collected in Iwate Prefecture, Japan. It was found on fallen dead branches and twigs of Japanese cedar,Cryptomeria japonica. The morphology of isolates on potato-dextrose agar (PDA), which were obtained from single ascospores ofS. cryptomeriae, was identical withGloeosporidina cryptomeriae, the causal fungus of Japanese cedar twig blight. In an inoculation test using single ascospore isolates, many minute black spots (sclerotioid bodies; sclerotules) and acervuli ofG. cryptomeriae were formed on the necrotic lesions, which developed into typical symptoms of Japanese cedar twig blight. These results show thatStromatinia cryptomeriae is the teleomorph ofG. cryptomeriae. On PDA, the fungus grew over a range of about 1 to 25°C, with the optimum growth at about 15–20°C. 相似文献
999.
Tetsuharu Iwata Tsuyoshi Hirose Masaru Nakamura Masatoshi Yamaguchi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1994,654(2)
A simple and highly sensitive high-performance liquid chromatographic method for the direct determination of urinary glucuronide conjugates is described. The method is based on the direct derivatization of the glucuronic acid moiety in glucuronide conjugates with 6,7-dimethoxy-1-methyl-2 (1 H)-quinoxalinone-3-propionylcarboxylic acid hydrazide. The derivatization reaction proceeds in aqueous solution in the presence of pyridine and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide at 0–37°C. The resulting fluorescent derivatives are separated on a C18 column using methanol—acetonitrile—0.5% triethylamine in water (1:1:2, v/v) as mobile phase, and are detected spectrofluorimetrically at 445 nm with excitation at 367 nm. The detection limits (signal-to-noise RATIO = 3) for the glucuronides are 13–48 fmol for an injection volume of 10 μl (130–480 fmol per 5 μl of human urine). The method was applied to the measurement of etiocholanorone-3-glucuronide and androsterone-3-glucuronide in human urine. The method is simple and rapid without conventional liquid—liquid extraction of the glucuronides from urine. 相似文献
1000.