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1.
E S Vylegzhanina N F Dmitrieva I B Naumova Iu I Chekanova Iu N Epishin T M Oksman 《Antibiotiki i khimioterapii͡a》1989,34(8):572-579
Lipoteichoic acid (LTA) of group A streptococci, type M 29 was studied. Chemical and 13C NMR spectroscopic analysis showed that the polymer contained poly(glycerophosphate) chain consisting of 12-14 glycerophosphate elements united by the 1----3 type phosphodiether bond and diglucosylglyceride. Oleic, stearic, palmitic and palmitoleic fatty acids predominated in the polymer composition. The content of the fatty acids amounted approximately to 2 per cent of LTA dry weight. The poly(glycerophosphate) chain contained 6-7 ether linked alanyl moieties. The results of the LTA biological study were analyzed in comparison to the data on a previous study of antitumor and cardiotoxic properties of teichoic acid from Streptomyces levoris K-3053 which is structurally close to the LTA hydrophilic moiety. It was assumed that the molecule negative charge had an effect on the cardiotoxic and antitumor activity. 相似文献
2.
Concordance between Parental Origin of Chromosome 13q Loss and 6p Duplication in Sporadic Retinoblastoma 下载免费PDF全文
A. Naumova M. Hansen L. Strong P. A. Jones D. Hadjistilianou D. Mastrangelo S. Griegel M. F. Rajewsky J. Shields L. Donoso M. Wang C. Sapienza 《American journal of human genetics》1994,54(2):274-281
Two hypotheses are capable of explaining nonrandom loss of one parent's alleles at tumor suppressor loci in sporadic cases of several pediatric cancers, including retinoblastoma—namely, preferential germ-line mutation or chromosome imprinting. We have examined 74 cases of sporadic retinoblastoma for tumors in which at least two genetic events—loss of heterozygosity for chromosome 13q markers and formation of an isochromosome 6p—have occurred. Sixteen cases were found to contain both events. In 13 of 16 such tumors, the chromosomes 13q that were lost and chromosomes 6p that were duplicated are derived from the same parent. These data may be explained within the framework of the genome imprinting model but are not predicted by preferential germ-line mutation. 相似文献
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4.
E. M. Tul'skaya G. M. Streshinskaya I. B. Naumova A. S. Shashkov L. P. Terekhova 《Archives of microbiology》1993,160(4):299-305
The cell-wall teichoic acids of Nocardiopsis dassonvillei IMRU 509T, IMRU 504 and IMRU 1250 and Nocardiopsis antarctius VKM Ac-836T have the same unique structure that has not heretofore been found in bacteria. The polymer is built of 10 to 13 repeating units:
相似文献
5.
Batdorj Enkhjin AlOgayil Najla Zhuang Qinwei Kim-wee Galvez Jose Hector Bauermeister Klara Nagata Kei Kimura Tohru Ward Monika A. Taketo Teruko Bourque Guillaume Naumova Anna K. 《Mammalian genome》2023,34(1):44-55
Mammalian Genome - Several lines of evidence suggest that the presence of the Y chromosome influences DNA methylation of autosomal loci. To better understand the impact of the Y chromosome on... 相似文献
6.
Polynucleotides adsorb on natural and model phospholipid membranes in the presence of Mg2+-cations. Adsorption of nucleic acids on membranes results in a considerable change of their secondary structure. The presence of model phosphatidylcholine membranes greatly stimulates the rate of the synthesis of RNA by E. coli RNA-polymerase on DNA template. 相似文献
7.
K. A. Malsagova Yu. D. Ivanov T. O. Pleshakova A. F. Kozlov N. V. Krohin A. L. Kaysheva I. D. Shumov V. P. Popov O. V. Naumova B. I. Fomin D. A. Nasimov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2014,8(3):220-225
The nanowire (NW) detection is one of the fast-acting and high-sensitive methods, which can recognize potentially relevant protein molecules. A NW-biosensor based on the silicon-on-insulator (SOI)-structures has been used for biospecific label-free real time detection of the NFATc1 (D-NFATc1) oncomarker. For this purpose, SOI-nanowires (NWs) were modified with aptamers against NFATc1 used as molecular probes. It was shown that using this biosensor it is possible to reach sensitivity of 10?15 M. This sensitivity was comparable to that of the NW-biosensor with immobilized antibodies used as macromolecular probes. The results demonstrate that approaches used in this study are promising for development of sensor elements for high-sensitive diagnostics of diseases. 相似文献
8.
Yeasts capable of utilizing the non-ionogenic surfactant Laurox-9 were identified as Cryptococcus humicolus (Daszewska) Golubev and Rhodotorula mucilaginosa (J?erg) Harrison. IR spectrometry used for the quantitative assay of Laurox-9 showed that R. mucilaginosa utilized it as a sole carbon source. The first step of Laurox-9 metabolism was its hydrolytic cleavage yielding lauric acid and polyethyleneglycol. Optimal conditions were found for the electron-cytochemical localization of hydrolase involved in the primary degradation of Laurox-9 by yeasts. Its localization of the exocellular components was established. 相似文献
9.
The work was aimed at studying the transformation of 2,4-diamino-6-nitrotoluene (2,4-DA), an intermediate product in 2,4,6-trinitrotoluene catabolism by microorganisms. The results allow one to propose the following scheme for the terminal steps of TNT preparatory metabolism: 2,4-DA----[phloroglucinol carboxylic acid]----phloroglucinol----pyrogallol----ring cleavage. 相似文献
10.
To study the evolution of the polymeric β-fructosidase (invertase) genes (SUC) of yeasts Saccharomyces, new SUC gene of S. cariocanus was cloned and sequenced and the nucleotide and amino acid sequences were compared for all known β-fructosidases of Saccharomyces species. The proteins showed 90–97% homology. The most divergent was S. bayanus β-fructosidase. The results testified again to high conservation of yeast β-fructosidases. Transitions C-T prevail in the total spectrum of nucleotide substitutions observed in the coding regions of the SUC genes; most of these transitions are in the third codon position and cause no changes in the amino acid sequences of the encoded proteins. The six Saccharomyces species each carry one (probably, non-telomeric) β-fructosidase gene. SUC is on chromosome IX in S. cerevisiae, S. bayanus, S. kudriavzevii, S. mikatae, and S. paradoxus and in a translocation region on chromosome XV in S. cariocanus.__________Translated from Molekulyarnaya Biologiya, Vol. 39, No. 3, 2005, pp. 413–419.Original Russian Text Copyright © 2005 by Korshunova, Naumova, Naumov. 相似文献
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