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1.
2.
Haruhide Kawabe Hiroshi Naganawa Shinichi Kondo Hamao Umezawa Susumu Mitsuhashi 《Microbiology and immunology》1978,22(9):515-521
A clinical isolate of Staphylococcus aureus resistant to gentamicin, kanamycin and 3′,4′-dideoxykanamycin B contained two enzymes capable of inactivating gentamicin, i.e., an aminoglycoside 2″-phosphotransferase and aminoglycoside acetyltransferase. 相似文献
3.
Primary structures of human protein kinase C beta I and beta II differ only in their C-terminal sequences 总被引:5,自引:0,他引:5
Two types of cDNA clones encoding human protein kinase C (PKC) were isolated from a spleen cDNA library using rabbit protein kinase C beta I/beta II cDNA as a hybridization probe. Nucleotide sequence analyses of these cDNA inserts revealed complete primary structures of two distinct types of human protein kinase C beta I and beta II which differ only in their C-terminal 50 or 52 amino acid residues. It was concluded that there exist four distinct types of PKC, PKC alpha, beta I, beta II and gamma, in human as well as rabbit, and that the corresponding sequences are strictly conserved among mammalian species. 相似文献
4.
Summary The purpose of this paper is to describe the immunocytochemical localization of M protein of vesicular stomatitis virus (VSV) in infected cells. Vero cells, MDBK cells, Swiss 3T3 cells, and BHK cells were examined at various times after infection. For immunofluorescent staining, the cells were fixed with PLP fixative and then treated with 0.05% Triton X-100 before incubation with antibodies. Three hours after infection, M protein exhibited diffuse immunostaining throughout the cytoplasm and later accumulated along the cell membrane. The localization of M protein differed from the granular localization of the nucleocapsid N protein of VSV in the cytoplasm. For electron microscopy, the cells were fixed first in a mixture of 2% paraformaldehyde and 0.05% glutaraldehyde and then with PLP fixative, this being followed by treatment with 0.05% saponin. They were then immunostained using the immunoperoxidase method. The M protein was found to be distributed throughout the cytoplasm and later under the cell membrane, especially at virus budding sites. We also used postembedding immunostaining and freeze-fracture immunostaining to avoid the translocation of M protein caused by the detergent treatment. These techniques confirmed our previous results. Our findings are consistent with the view that the M protein of VSV is synthesized on free ribosomes and is then associated with the cell membrane where viral assembly may occur.S. Ohno was a visiting fellow from the Fogarty International Center at the National Institutes of Health, USA, from September 1981 to August 1983, while some parts of this work were in progress. 相似文献
5.
In vitro splicing of a chicken delta-crystallin pre-mRNA in a mammalian nuclear extract 总被引:6,自引:0,他引:6
An in vitro splicing system was constructed using portions of chicken delta-crystallin pre-mRNA synthesized in vitro and a HeLa nuclear extract. Analysis of the reaction products revealed that about 25% of the pre-mRNA was precisely spliced at 30 degrees C in 2 h under the standard conditions. The other major products of the reaction detected were a 5'-exon fragment and three RNA species showing unusual electrophoretic mobilities on polyacrylamide gels. Structural analyses showed that these three RNAs contain a branch (lariat) structure as seen in the in vitro splicing reactions of human beta-globin, adenovirus, and yeast pre-mRNAs. In addition, methylation at the N-7 position of the blocking guanosine of the 5'-terminal cap structure of pre-mRNA has been suggested to play an important role in the splicing reaction. 相似文献
6.
H Wada S Ohno K Kubo C Taya S Tsuji S Yonehara K Suzuki 《Biochemical and biophysical research communications》1989,165(1):533-538
By the use of cloned cDNAs for protein kinase C isozymes alpha, beta I, beta II, gamma, and those for novel protein kinase C, epsilon and zeta, the expression of the corresponding mRNA species was examined in various mouse tissues, human lymphoid cell lines, and mouse cell lines of neuronal origin. In adult brain, mRNAs for all the isozymes of PKC family are expressed. However, the expression of these mRNA species in brain is low at birth. A similar pattern of expression was also observed for beta I/beta II mRNAs in spleen. These expression patterns are in clear contrast to that for beta I/beta II mRNAs in thymus where the mRNAs are expressed at birth and the levels of expression decrease with age. Human lymphoid cell lines express large amounts of PKC beta mRNAs in addition to PKC alpha. Further, nPKC epsilon mRNA is expressed in some of these cell lines. On the other hand, all the mouse cell lines of neuronal origin tested express nPKC epsilon and zeta in addition to PKC alpha. In a mouse neuroblast cell line, Neuro 2a, down modulation of mRNAs for both PKC alpha and nPKC epsilon was observed in association with in vitro differentiation. 相似文献
7.
An alkaline solution of bismuth subnitrate reacted well with the cell membranes and cell walls of formaldehyde-glutaraldehyde potassium permanganate fixed Alternaria spores, demonstrating them with greater contrast than in sections stained with uranyl acetate and lead citrate. Optimal fine structure of fungal spores was obtained by en bloc staining with alkaline bismuth solution after aldehyde and permanganate fixation. The contrast of the cell organelles and cell walls was high enough in sections cut after the alkaline bismuth en bloc stain for direct ultrastructural observation. Our results indicate that the alkaline bismuth stain is useful either as an en bloc or section stain for aldehyde and permanganate fixed fungal spores. 相似文献
8.
A new member of the protein kinase C family, nPKC theta, predominantly expressed in skeletal muscle.
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S Osada K Mizuno T C Saido K Suzuki T Kuroki S Ohno 《Molecular and cellular biology》1992,12(9):3930-3938
A new protein kinase C (PKC)-related cDNA with unique tissue distribution has been isolated and characterized. This cDNA encodes a protein, nPKC theta, which consists of 707 amino acid residues and showed the highest sequence similarity to nPKC delta (67.0% in total). nPKC theta has a zinc-finger-like cysteine-rich sequence (C1 region) and a protein kinase domain sequence (C3 region), both of which are common in all PKC family members. However, nPKC theta lacks a putative Ca2+ binding region (C2 region) that is seen only in the conventional PKC subfamily (cPKC alpha, -beta I, -beta II, and -gamma) but not in the novel PKC subfamily (nPKC delta, -epsilon, -zeta, and -eta). Northern (RNA) blot analyses revealed that the mRNA for nPKC theta is expressed predominantly in skeletal muscle. Furthermore, nPKC theta mRNA is the most abundantly expressed PKC isoform in skeletal muscle among the nine PKC family members. nPKC theta expressed in COS1 cells serves as a phorbol ester receptor. By the use of an antipeptide antibody specific to the D2-D3 region of the nPKC theta sequence, nPKC theta was recognized as a 79-kDa protein upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis in mouse skeletal muscle extract and also in an extract from COS1 cells transfected with an nPKC theta cDNA expression plasmid. Autophosphorylation of immunoprecipitated nPKC theta was observed; it was enhanced by phosphatidylserine and 12-O-tetradecanoylphorbol-13-acetate but attenuated by the addition of Ca2+. These results clearly demonstrate that nPKC theta should be considered a member of the PKC family of proteins that play crucial roles in the signal transduction pathway. 相似文献
9.
Shinichi Ikemoto Seiji Wada Masato Kamizuru Nobuyuki Hayahara Taketoshi Kishimoto Masanobu Maekawa 《Cancer immunology, immunotherapy : CII》1992,34(5):289-293
Summary The authors examined interleukin-2 (IL-2) production and interferon (IFN) production of peripheral blood mononuclear cells in 28 patients with renal cell carcinoma and 17 control subjects. The peripheral blood was obtained prior to the initiation of therapeutic procedures. The patients were divided into two groups according to tumor size, 5 cm and >5 cm. The production of IL-2 and IFN was measured by immunoradiometric assay. As a result, in the patients with tumors >5 cm, IL-2 and IFN production was impaired. However, in the patients with tumors 5 cm, IFN production was enhanced, though IL-2 production was not significantly different from that of the control subjects. There was no significant correlation between IL-2 production and IFN production. 相似文献
10.
Susumu Ohno 《Human genetics》1992,90(4):342-345
On the average, 30% of the residues in a protein are members of peptidic palindromes, tripeptidic and longer. This percentage may go up to 50% in histones and certain other DNA binding proteins. The longest peptidic palindrome encountered thus far was 14 residues in length. However, there is every reason to expect even longer peptidic palindromes in other proteins not yet analyzed.This article is dedicated to Professor Ulrich Wolf in honor of his 60th birthday 相似文献