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981.
982.
983.
Amino-acid substitutions at codon 13 of the N-ras oncogene in human acute myeloid leukaemia 总被引:1,自引:0,他引:1
J L Bos D Toksoz C J Marshall M Verlaan-de Vries G H Veeneman A J van der Eb J H van Boom J W Janssen A C Steenvoorden 《Nature》1985,315(6022):726-730
DNAs from four out of five patients with acute myeloid leukaemia (AML) tested by an in vivo selection assay in nude mice using transfected mouse NIH 3T3 cells were found to contain an activated N-ras oncogene. Using a set of synthetic oligonucleotide probes, we have detected a mutation at codon 13 in all four genes. The same codon is mutated in an additional AML DNA that is positive in the focus-formation assay on 3T3 cells. DNA from the peripheral blood of one patient in remission does not contain a codon 13 mutation. 相似文献
984.
985.
J. Schröder 《Cellular and molecular life sciences : CMLS》1968,24(1):91-91
Summary Cells ofRhodospirillum rubrum were cultured aerobically or semiaerobically in the dark and anaerobically in the light. The investigation of acid extracts of these cells showed, that this bacterium contained no ascorbic acid under all conditions of cultivation. 相似文献
986.
J. Rosmus Olga Vančíková J. Marc Z. Deyl 《Cellular and molecular life sciences : CMLS》1967,23(11):898-898
Zusammenfassung Die Reaktion zwischen Kollagen und FeIII wurde studiert. Es zeigte sich, dass das Eisen an die Sequenzen des Typs Ala-Asp-Gly gebunden wird. Weiter wurde gefunden, dass 1 mol Ratten-Tropokollagen 1 mol Cystein als Sequenz Cys-Ala-Asp-Gly enthält.
S. Bump, Z. Deyl andJ. Rosmus, Communication IV, Experientia23, 518 (1967). 相似文献
S. Bump, Z. Deyl andJ. Rosmus, Communication IV, Experientia23, 518 (1967). 相似文献
987.
Transducing phage for Pseudomonas putida 总被引:3,自引:0,他引:3
988.
989.
Mesodinium rubrum (Lohmann 1908) Jankowski 1976 (= Myrionecta rubra) is a common photosynthetic marine planktonic ciliate which can form coastal red-tides. It may represent a 'species complex' and since Darwin's voyage on the Beagle, it has been of great cytological, physiological and evolutionary interest. It is considered to be functionally a phytoplankter because it was thought to have lost the capacity to feed and possesses a highly modified algal endosymbiont. Whether M. rubrum is the result of a permanent endosymbiosis or a transient association between a ciliate and an alga is controversial. We conducted 'feeding' experiments to determine how exposure to a cryptophyte alga affects M. rubrum. Here we show that although M. rubrum lacks a cytostome (oral cavity), it ingests cryptophytes and steals their organelles, and may not maintain a permanent endosymbiont. M. rubrum does not fall into recognized cellular or functional categories, but may be a chimaera partially supported by organelle robbery. 相似文献
990.
L. Fanuel I. Thamm V. Kostanjevecki B. Samyn B. Joris C. Goffin J. Brannigan J. Van Beeumen J. M. Frère 《Cellular and molecular life sciences : CMLS》1999,55(5):812-818
Two new enzymes which hydrolyse D-alanyl-p-nitroanilide have been detected in Ochrobactrum anthropi LMG7991 extracts. The first enzyme, DmpB, was purified to homogeneity and found to be homologous to the Dap protein produced
by O. anthropi SCRC C1-38 (ATCC49237). The second enzyme, DmpA, exhibits a similar substrate profile when tested on p-nitroanilide derivatives
of glycine and L/D-alanine, but the amounts produced by the Ochrobactrum strain were not sufficient to allow complete purification. Interestingly, the DmpA preparation also exhibited an L-aminopeptidase
activity on the tripeptide L-Ala-Gly-Gly but it was not possible to be certain that the same protein was responsible for both
p-nitroanilide and peptide hydrolysing activities. The gene encoding the DmpA protein was cloned and sequenced. The deduced
protein sequence exhibits varying degrees of similarity with those corresponding to several open reading frames found in the
genomes of other prokaryotic organisms, including Mycobacteria. None of these gene products has been isolated or characterised,
but a tentative relationship can be proposed with the NylC amidase from Flavobacterium sp. K172.
Received 7 December 1998; received after revision 15 March 1999; accepted 22 March 1999 相似文献