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911.
Antimycobacterial drugs such as isoniazid; ethionamide and thiocarlide are inhibitors of mycolic acid synthesis in Mycobacterium tuberculosis. Isoniazid in particular appears to block the formation of a Δ5−C24:1 fatty acid which could be a precursor of mycolic acids. 相似文献
912.
Yoshitaka Shimizu Shinjiro Todo Shinsaku Imashuku 《Prostaglandins & other lipid mediators》1986,32(4)
To study the precise mechanism of cytotoxic activity of PGD2 or Δ12-PGJ2 (a biological active metabolite of PGD2), we examined the effect of various compounds on PGD2 or Δ12-PGJ2 cytottoxic, using a human neuroblastoma cell line (NCG). Cycloheximide (CHM) specifically protected PGD2 cytotoxicity on NCG cells. When Δ12-PGJ2 was tested, CHM exhibited a similar rescue effect. Puromycin, mitomycin C, and α-amanitin did not affect PGD2 or Δ12-PGJ2 cytotoxicity. Emetine showed a variable and no consistent rescue effect CHM may have been active at the primary site where PGD2 or Δ12-PGJ2 exerts its cytotoxicity. This is the first report indicating that CHM reduces the cytotoxicity induced by PGD2 or Δ12-PGJ2. 相似文献
913.
G. Suzuki M. Watanabe N. Kai N. Matsuda K. Toriyama S. Takayama A. Isogai K. Hinata 《Molecular & general genetics : MGG》1997,256(3):257-264
Two self-incompatibility genes in Brassica, SLG and SRK (SLG encodes a glycoprotein; SRK encodes a receptor-like kinase), are included in the S multigene family. Products of members of the S multigene family have an SLG-like domain (S domain) in common, which may function as a receptor. In this study, three clustered
members of the S multigene family, BcRK1, BcRL1 and BcSL1, were characterized. BcRK1 is a putative functional receptor kinase gene expressed in leaves, flower buds and stigmas, while BcRL1 and BcSL1 are considered to be pseudogenes because deletions causing frameshifts were identified in these sequences. Sequence and expression
pattern of BcRK1 were most similar to those of the Arabidopsis receptor-like kinase gene ARK1, indicating that BcRK1 might have a function similar to that of ARK1, in processes such as cell expansion or plant growth.
Interestingly, the region containing BcRK1, BcRL1 and BcSL1 is genetically linked to the S locus and the physical distance between SLG, SRK and the three S-related genes was estimated to be less than 610 kb. Thus the genes associated with self-incompatibility exist within a cluster
of S-like genes in the genome of Brassica.
Received: 15 April 1997 / Accepted: 13 June 1997 相似文献
914.
T Sugiyama A Kittaka H Takayama M Tomioka Y Ida R Kuroda 《Nucleic acids symposium series》2000,(44):41-42
We report the first example of chemical cross-linking of 5-formyl-2'-deoxyuridine containing oligonucleotides with oligopeptides through a Schiff base formation. Twenty amino acid residue peptides investigated here were derived from the DNA binding site of RecA protein. We have demonstrated that the lysine residue placed at the 6th or 8th position from the N-terminus of the peptide directly contacts with DNA. 相似文献
915.
BackgroundEvolutionarily homologous proteins bovine α-lactoalbumin (αLA) and hen egg-white lysozyme (HEL) are very similar in primary, secondary and tertiary structures involving the location of disulfide-bridges (S–S), and are resistant to the action of hydrolytic enzymes and reagents. It is of interest to examine and compare the difference in backbone cleavage characteristics, by using reductive and hydrolytic reagents.MethodsIn-source decay (ISD) combined with matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS), reductive treatment of αLA and HEL with dithiothreitol (DTT) and acid hydrolysis with trifluoroacetic acid (TFA) were employed to examine the difference in the backbone cleavage characteristics of αLA and HEL.ResultsThe treatment of αLA and HEL with DTT/AcOHNH3 resulted in similar cleavage behaviors of the backbone N-Cα and S–S bonds, i.e., the enhancements of the intensity and m/z range of sequence-reflected fragment ions were very similar. However, the treatment of αLA with DTT/TFA resulted in unexpected residue-specific degradation at the peptide bond of the Asp-Xxx, Xxx-Ser/Thr, Gln-Xxx, Xxx-Gly and Gly-Xxx residues, while HEL did not occur such degradation.ConclusionsThe results obtained above indicate that acidic αLA is very sensitive to acidic additive such as TFA, while basic HEL is resistance to acidic additives.General significanceThe study demonstrates the sensitive and resistant of evolutionary homologous proteins αLA and HEL to the acid hydrolysis and these characters come from acidic and basic nature of the proteins. 相似文献
916.
T Ishikawa S Takayama T Kitagawa 《Virchows Archiv. B, Cell pathology including molecular pathology》1978,28(3):235-242
Unscheduled DNA synthesis in highly differentiated ganglion cells of adult medaka (Oryzias latipes) was demonstrated by autoradiography. For this, part of bony skull of the fish was surgically removed and the brain of the living fish was directly exposed to a solution of 2 carcinogen and 3H-TdR. This technique is suitable for precise measurement of DNA repair synthesis in non-dividing cells of the central nervous system in vivo. Using this system, the effect of aging on the levels of DNA repair was investigated. There was no age-associated change in the ability of repair in ganglion cells of the medaka of various ages. 相似文献
917.
Naoya Takayama Alex Murison Shin-ichiro Takayanagi Christopher Arlidge Stanley Zhou Laura Garcia-Prat Michelle Chan-Seng-Yue Sasan Zandi Olga I. Gan Héléna Boutzen Kerstin B. Kaufmann Aaron Trotman-Grant Erwin Schoof Ken Kron Noelia Díaz John J.Y. Lee Tiago Medina Daniel D. De Carvalho Mathieu Lupien 《Cell Stem Cell》2021,28(3):488-501.e10
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918.
The conditions for rapid growth of Begonia plantlets from budsregenerated on leaf segments were studied, the ultimate aimbeing to develop a mass propagation procedure. Plantlet growthwas stimulated in submerged culture by Murashige-Skoog's mediumwith 10 or 30 g/liter sucrose, but was inhibited by a lower( x1/4) concentration of basal medium. Root development wassuperior in the lower strength medium. The greater amount ofsucrose, 30 g/liter, stimulated root growth more than the 10g/liter did. Buds required kinetin at a concentration of 0.3to 1 mg/liter, but did not require auxin. Plantlets reachedmaximum growth after 3 weeks of cultivation in 300-ml Erlenmeyerflasks containing 30 to 150 ml of medium that were shaken at180 rpm. Cultivation in jar and bubble column fermentors appearsto be advantageous for the large scale propagation of Begoniaplantlets. (Received December 8, 1980; Accepted February 4, 1981) 相似文献
919.
Takayuki Nagao Kimiaki Saito Emiko Hirayama Kumi Uchikoshi Kiyotaka Koyama Shinsaku Natori Naoko Morisaki Shigeo Iwasaki Tijiro Matsushima 《Mutation research》1989,215(2):173-178
Ptaquiloside, a potent carcinogen of an illudane-type sesquiterpene glycoside isolated from Pteridium aquilium, and its related compounds, hypolosides having the same nucleus isolated from the Pteridaceae, exhited marked mutagenicity in the modified Ames test with Salmonella typhimurian TA98 and A100 using a preincubation at pH 8.5 Illudins M and S, sesquiterpenes of the same illudane type from basidiomycetes, also exhibited mutagenicity. The structural requirements for mutagenicity are discussed. 相似文献
920.