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1.
A new snake-eel,Apterichtus keramanus, is described on the basis of a single 276-mm TL specimen trawled from the coast of Kerama Islands, Okinawa Prefecture, Japan.
The species is unique in the genus in having the posterior nostril opening entirely inside the mouth and a dark band running
from the anteroventral margin of the eye to the upper lip. 相似文献
2.
T Maruyama T Nomiyama M Asahi N Mori E Ono A Kawahara S Fujimoto 《Histology and histopathology》1989,4(1):85-94
Based on ultrastructural features of cellular components of a hemangiopericytoma, hyperplastic cells are classifiable into fibroblast-like (group I), endotheloid (group II) and pericyte-like (group III) cells. The transformation of the group I cells to the group II, or to the group III cells, is pronounced in our electron micrographs and this may imply that the group I cell is the principal cell of origin in this neoplasm. The smooth muscle-like (group IV) cells comprising the media of the arteries and veins in this neoplasm may represent modified, possibly de-differentiated smooth muscle cells reacted to the neoplastic proliferation of the surrounding adventitial (group I) cells. 相似文献
3.
Chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) of malesterile tobacco plants obtained by fusion of Nicotiana tabacumprotoplasts and X-irradiated N. debneyi protoplasts were analyzed.Digestion of cpDNA isolated from ten male sterile lines withfour restriction endonucleases (EcoRI, XhoI, SmaI and HindIII)indicated that these lines possessed either one or the otherparental chloroplast genome. Neither mixture of two types ofcpDNA nor unique restriction fragments were detected in anyof the cases examined. The genetic constitution of chloroplastgenomes identified by restriction analysis of cpDNA showed goodagreement with that based on isoelectric focusing of the largesubunit of the Fraction I protein. The mtDNA from five fusion-derivedmale sterile plants showed banding patterns quite differentfrom each other and from the parental plants. Each plant exhibitednew restriction fragments not found in the parental species.These findings indicate that recombinational events in the mitochondrialgenomes take place rather frequently in the mixed cytoplasmsafter protoplast fusion, whereas the mixed chloroplasts becomesegregated to homogeneity. (Received June 19, 1987; Accepted October 5, 1987) 相似文献
4.
Identification of jasmonic acid in Mimosa pudica and its inhibitory effect on auxin- and light-induced opening of the pulvinules 总被引:1,自引:0,他引:1
Jasmonic acid was identified from Mimosa pudica L. plants by mass spectrometry, high performance liquid chromatography and thin layer chromatography. Effects of authentic jasmonic acid on pulvinule movement and transpiration of the pinnae were compared with those of abscisic acid. Jasmonic acid and abscisic acid each at 10−5 M inhibited both auxin- and light-induced opening of the pulvinules. A closure-inducing activity of jasmonic acid at 10−4 M was greater than that of abscisic acid at 10−4 M. Pinnae transpiration was reduced by 10−5 M abscisic acid but not by 10−4 M jasmonic acid. 相似文献
5.
NADPH-cytochrome c reductase, strictly NADPH-cytochrome P-450reductase, was purified by chromatography through DEAE-cellulose,2',5'-ADP-Sepharose, and Sephadex G-100 columns after solubilizationfrom microsomes from Ceratocystis fimbriata-infected sweet potatoroot tissue with Emulgen 913. The enzyme existed in three formsafter solubilization which migrated to positions correspondingto molecular weights of 81,000, 75,000 and 72,000 on an SDS-polyacrylamidegel. Trypsin treatment of the enzyme species with the largestpolypeptide yielded the species with the smallest one. Aftersucrose density gradient centrifugation of the pellet fractionobtained by centrifugation at 100,000?g of the crude extract,the enzyme species with the largest polypeptide was presentin the particulate fractions, whereas that with the smallestone was only found at the top of the gradient. We conclude thatthe enzyme species with the largest polypeptide is in an intact,amphipathic form, whereas that with the smallest one, and probablyalso the other species, is its hydrophilic domain produced byan endogenous protease(s). The Km values of the enzyme in theintact form for NADPH and cytochrome c were 7.7 and 2.3 µM,respectively.
1 Present address: Laboratory of Food Hygienics, Faculty ofAgriculture, Kagawa University, Miki-cho, Kida-gun, Kagawa 761-07,Japan. (Received September 6, 1984; Accepted December 27, 1984) 相似文献
6.
Yoshihiko Sawa Ken-ichiro Shibata Mamoru Noda Tsuguo Watanabe 《Microbiology and immunology》1994,38(4):257-262
A 90 kDa protein of Mycoplasma salivarium was released from cell membranes of the organism with Triton X-100 and purified by ion-exchange chromatography and chromatofocusing. The protein was eluted at pH 5.5 by chromatofocusing. The protein was shown to react with the Fc fragments of IgG from human and nine different animal species and did not distinguish between IgG from different species, while protein A, tested for comparative purposes, displayed a strong specificity for human and swine IgG. Furthermore, the protein reacted with antigen specific goat IgG (specific for gamma chains of human IgG), sheep red blood cells (SRBC) sensitized with rabbit antiserum to SRBC, that is, the Fc part of rabbit IgG, and concanavalin A as well. These findings may suggest that the protein is a lectin which binds the carbohydrate moiety of the Fc part of IgG. 相似文献
7.
Tetsuya Oguma Asahi Matsuyama Mamoru Kikuchi Eiichi Nakano 《Applied microbiology and biotechnology》1993,39(2):197-203
The gene for cyclomaltodextrinase (CDase; EC 3.2.1.54) from Bacillus sphaericus E-244 was cloned in the recombinant plasmid pCD629. Sequencing a portion of pCD629 revealed a unique open reading frame of 1,773 nucleotides coding for a 591-amino-acid polypeptide. The deduced polypeptide sequence showed about 50% homology with that of a neopullulanase, and was slightly homologous to those of the cyclodextrin glucanotransferases and the -amylases. The optimum pH, specific activity and K
m value for -cyclodextrin of the CDase that has been produced in Escherichia coli cells were 8.0, 16.4 units/mg protein, and 0.41 mm, respectively. These values were almost identical to those from B. sphaericus E-244.
Correspondence to: T. Oguma 相似文献
8.
Ota Yoko; Ario Takeshi; Hayashi Koji; Nakagawa Tsuyoshi; Hattori Tsukaho; Maeshima Masayoshi; Asahi Tadashi 《Plant & cell physiology》1992,33(3):225-232
Catalases purified from endosperm glyoxysomes and non-specializedmicrobodies from hypocotyls of castor bean seedlings differedin their specific activity [90164 and 0.894.9kunits (mg protein)1, respectively] and in their constituentsubunits [two subunits of 54 and 56 kDa for the endosperm enzymeand only one of 56 kDa for the hypocotyl enzyme]. Immunoblotanalysis also showed that particulate fractions from the endospermsand from etiolated and green cotyledons contained two catalasesubunits of 54 and 56 kDa, whereas such fractions from the hypocotylsand roots contained only the 56-kDa subunit. Leaf peroxisomesfrom green leaves had two catalase subunits of around 55 kDaeach. Results of translation in vitro indicated that the 54-and 56-kDa subunits were translated from distinct mRNAs andlevels of both mRNAs increased in the endosperms during germination,prior to increases in levels of catalase proteins. In the hypocotyls,the 56-kDa subunit seemed to be synthesized constitutively.
1Present addresses: YO, Toyota Central Institute, 31-9 Musashizuka,Nagabuchi, Nagakute, Aichi 480-11, Japan 相似文献
9.
Catalase was isolated in a pure form from sweet potato rootmicrobodies by simple procedures including ammonium sulfatefractionation and Sepharose 6B column chromatography. A singleprotein band was detected after polyacrylamide gel electrophoresisof the purified preparation. The catalase consisted of polypeptideswith a molecular weight of 60,000 when analyzed by sodium dodecylsulfate-polyacrylamidegel electrophoresis, while the molecular weight of the enzymewas about 240,000 when estimated from sucrose density gradientcentrifugation. The enzyme's ratio of absorbance at 280 nm tothat at 405 nm was about twice that of mammalian catalase. Thecatalase showed a maximal activity at pH 6.58.5 but wasstable only at alkaline pHs. In double immunodiffusion tests,antiserum against the purified preparation formed a single precipitinline with the crude soluble fraction from sweet potato roottissue as well as with the purified preparation. The antiserumhad no ability to inhibit the activity, but catalase in boththe crude fraction and the purified preparation was completelyprecipitated by the antiserum. (Received August 20, 1981; Accepted January 5, 1982) 相似文献
10.
Carotenoid photobleaching induced by photosystem II action wasstudied using membrane fragments of the blue-green alga Anabaenavariabilis. Special attention was paid to the action of O2. Carotenoid photobleaching elicited by carbonyl cyanide m-chlorophenylhydrazone(CCCP) depended on O2. However, the addition of H2O2, sodiumsilicotungstate or potassium ferricyanide (Ferri), an electronacceptor for reaction center II action, removed the O2-dependency.These results indicate that O2 acts as the electron acceptorfor this reaction. When both CGCP and Ferri were present, a short illumination(0.25 sec) caused a rapid photobleaching followed by a slowrecovery in the subsequent dark period. The spectrum of theabsorption decrease in the light was identical with that ofthe absorption increase in the subsequent dark, indicating thata reversible process is involved in the carotenoid photobleaching.The size in the dark recovery relative to the light bleachingbecame larger under anaerobic conditions and smaller under higherpartial pressure of O2. The reuslts were interpreted as indicatingthat O2 does not function in the primary process including areversible bleaching step, but is involved in the slow and irreversiblebleaching process. (Received April 3, 1978; ) 相似文献