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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   
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A new system was designed to detect staphylococcal exfoliative toxin A (ETA) and B (ETB) genes by the polymerase chain reaction (PCR). The primer pairs for the ETA gene (eta) were 20 and 20-mer, and its PCR product was a 741-bp eta fragment, while the primer pairs for the ETB gene (etb) were also 20 and 20-mer, and its PCR product was a 629-bp etb fragment. When these primers were simultaneously used in the PCR, the two types of ET were clearly detected as two bands in an ETA and ETB double-producer using only one colony within 3 hr. We examined 66 strains of Staphylococcus aureus isolated from patients with staphylococcal scalded skin syndrome (SSSS) and compared the results obtained by ELISA and PCR. The same results were obtained for 56 of the strains, i.e., 30 strains were ETA producers, 20 strains were ETB producers, and 6 strains were double-producers. However, positive results were obtained for 5 of the 10 non-ET-producing strains. Two of these strains were judged by PCR as ETA producers and three as ETB producers. Thus, PCR is very sensitive and rapid in detecting ETA and ETB gene fragments in colonies isolated from patients with SSSS.  相似文献   
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The gene coding for four subunits of cytochrome aa3-type oxidase was isolated from a genomic DNA library of the thermophilic bacterium PS3 and sequenced. The N-terminus of each subunit was also sequenced to verify the initiation site of the reading frame. The deduced amino acid sequences contained 615 amino acid residues for subunit I (CO1/caaB product), 333 residues for subunit II (CO2/caaA product), 207 residues for subunit III (CO3/caaC product), and 109 residues for subunit IV (CO4/caaD product) after processing. Re-examination of the sequencing of caa revealed a longer open reading frame for CO1, which contains 14 transmembrane segments instead of 12 [Sone et al. (1988) J. Biochem. 103, 606-610], although the main portions of the sequences constituting cytochrome a (FeA), cytochrome a3 (FeB), and CuB are correct. PS3 CO2 has an additional sequence for cytochrome c after the CuA binding protein portion with 2 transmembrane segments, which is homologous to the mitochondrial counterpart. PS3 CO3 has DCCD-binding glutamyl residues but contains only 5 transmembrane segments, unlike the mitochondrial counterpart, which has 7 segments. The subunits of PS3 cytochrome oxidase (aa3-type) show clear similarity in amino acid sequences with those of cytochrome bo-type oxidase from Escherichia coli as well, in spite of the difference of hemes. PS3 CO3 and CO4 are much more similar to E. coli CO3 and CO4 than to mitochondrial CO3 and CO4, respectively.  相似文献   
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Using the sequence homology approach for cloning related genes within the G-protein-coupled receptor gene family, we have cloned the gene for the rat beta 1-adrenergic receptor (beta 1-AR). The rat beta 1-adrenergic receptor gene was isolated from a lambda EMBL3 rat genomic DNA library using the hamster beta 2-adrenergic receptor (beta 2-AR) coding sequence as a probe under low stringency hybridization conditions. The rat beta 1-AR gene encodes a protein of 466 amino acids that contains one consensus site for N-linked glycosylation (Asn-15) and three consensus sites for cAMP-dependent protein kinase phosphorylation (Ser-296, Ser-301, and Ser-401). The encoded rat beta 1-AR is 98 and 91% similar at the amino acid level with the human beta 1-AR in the transmembrane domains and in the overall sequence, respectively. Genomic Southern blot and gene dosage analyses indicate that the rat beta 1-AR gene is a single copy gene. The tissue distribution of the rat beta 1-AR mRNA was highest in the pineal gland with other brain regions and peripheral tissues, including the heart, expressing the mRNA at moderate levels. The bacteriophage clone containing the rat beta 1-AR gene with its natural promoter was co-transfected with the selectable marker (pRSVneo) conferring neomycin resistance into beta 1-AR-deficient mouse L cells. Analyses of the selected transfectant demonstrates efficient expression of the beta 1-AR gene and functional receptor. 125I-Labeled iodocyanopindolol bound transfectant membranes with an affinity of KD = 24 pm; the beta 1-AR-selective antagonist ICI 89,406 displaced iodocyanopindolol binding with a Ki approximately 140 times lower than that for the beta 2-AR-selective antagonist ICI 118,551. In addition, in the transfectant cell line, adenylylcyclase was stimulated by beta-adrenergic receptor agonists with the rank order of potency of isoproterenol greater than norepinephrine = epinephrine, consistent with properties expected of the beta 1-AR subtype.  相似文献   
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N--benzoyl D,L-arginine p-nitroanilide (BAPA), leucine p-nitroanilide(LPA) and casein hydrolytic activities were assayed in germinatingcotyledons. BAPA hydrolytic activity was not detected in dryseeds, but increased rapidly from 1 to 4 days of germinationand then decreased. LPA and casein hydrolytic activities weredetected in dry seeds and increased from 2 to 4 days. Caseinhydrolytic activity decreased faster than the other two activities. BAPA hydrolytic enzyme was partially purified. It was inhibitedby p-chloromercuribenzoate and activated by ß-mercaptoethanoland dithiothreitol, but was not affected by EDTA, phenylmethylsulfonylfluoride, pumpkin trypsin inhibitor and several divalent cations.It had no ability to hydrolyze globulin or the chain to produce Fß or smaller polypeptides,respectively, which was referred to as proteolytic activityI in the preceding paper (14), but released small peptides andamino acids from the chain and Fß. However, it wasdifferent from proteolytic enzyme II which was present in dryseeds and inhibited by EDTA (14). Pumpkin trypsin inhibitor was purified. Its molecular weightwas estimated to be 10,500 by gel filtration. It did not inhibitthe BAPA hydrolytic enzyme. Both proteolytic activities I andII were also not reduced by the inhibitor (14). The inhibitoryactivity decreased gradually during germination. (Received November 9, 1979; )  相似文献   
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A highly sensitive procedure of solid-phase radioimmunoassay (RIA) was developed for the detection of measles IgG antibody. HeLa cells persistently infected with measles virus were used as a solid-phase antigen. This technique was applied to the detection of measles IgG antibody in patients with subacute sclerosing panencephalitis (SSPE) and multiple sclerosis. Normal subjects having experienced natural measles or measles vaccination and patients with various neurological diseases of non-virus nature were also examined as control groups. Measles antibody was detected at high titers in both the sera and cerebrospinal fluid of SSPE patients. Moreover, RIA/HI ratios of SSPE patients were significantly higher than those of normal subjects, suggesting the presence in the formers of antibodies to nucleocapsids at high titers as well as to viral envelopes. On the other hand, no significant difference was found in both RIA and HI titers between the sera of multiple sclerosis and those of various neurological diseases.  相似文献   
9.
The effects of thirteen kinds of powdered herbal drugs and seven kinds of commercial dry condiments on the growth and toxin production ofAspergillus parasiticus, A. flavus,A. ochraceus, andA. versicolor were observed by introducing these substances into culture media for mycotoxin production.Of the twenty samples tested, cinnamon bark completely inhibited the fungal growth, while the others only inhibited the toxin production.The inhibitors were easily extracted from the samples with solvents such as hot water, chloroform, or ethanol.The extracts from coptis, philodendron bark, mustard, green tea leaves, and zanthoxylum completely inhibited the aflatoxin production ofA. parasiticus, however, they had little or no inhibitory effect againstA. flavus.  相似文献   
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A heat stable globulin present in the cotyledons of pumpkinseeds was prepared as crystals which were soluble in a dilutesaline solution below pH 4.5 or in a solution with a high ionicstrength at neutral pHs. The protein was nearly homogeneousby ultracentrifuge analysis, and had a molecular weight of about112,000 daltons. Sodium dodecyl sulfate-polyacrylamide gel electrophoresisseparated the globulin into two subunits, and ß,corresponding to molecular weights of about 63,000 and 56,000daltons, respectively. By reduction of disulfide bonds, thetwo subunits were each separated into two polypeptide chainswith molecular weights of around 36,000 and 22,000 daltons,judged by gel electrophoresis. The amino acid composition ofwhole globulin indicated high contents of arginine, glutamicacid and aspartic acid. The total number of half-cystine residuewas nine and only one residue was shown to be free. The subunitstructure of the globulin is discussed. The protein has beenshown to have oxaloacetate decarboxylase activity, and thisfact was confirmed. However, the activity decreased markedlyat pH 4.5 in a fairly short period. It did not require Mn++,and the Km for oxaloacetate was determined to be 4.1 mM. (Received April 9, 1976; )  相似文献   
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