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81.
82.
The structure of the carbohydrate moiety of actinoidins A and B was found with partial acid hydrolysis (metanolysis) of the antibiotics and their methyl derivatives and the method of periodate oxidation. Actinoidins A and B had 3 carbohydrate branches presented by the residues of monosugars of D-mannopyranose and 2, 3, 6-tridesoxy-3-amino-4-O-methyl-L-arabinopyranose(L-actinosamine) and disaccharide of 2-O-(2, 3, 6-tridesoxy-3-amino-L-arabinopyranosyl)-D-glucopyranose. 相似文献
83.
Fragments of genes of the greenlike form I ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) of eight species of haloalkaliphilic obligately autotrophic sulfur-oxidizing bacteria of the genus Thioalkalivibrio have been revealed and sequenced using previously developed oligonucleotide primers. The data obtained are used for the construction of phylogenetic trees on the basis of nucleotide sequences of RuBisCO genes and their conceptual translations into amino acid sequences. Comparative analysis of the 16S rRNA and RuBisCO gene trees reveals discrepancies between their topologies. According to a RuBisCO gene analysis, the genus Thioalkalivibrio is not monophyletic, and its inner divergence conforms to the significant morphological differences observed between the species. Presumably, horizontal (interspecies) gene transfer was involved in the evolution of the genus Thioalkalivibrio. 相似文献
84.
Mel'nyk VM Spiridonova KV Andrieiev IO Strashniuk NM Kunakh VA 《T?Sitologii?a i genetika》2004,38(3):16-21
18S-25S rDNA sequence in genomes of G. lutea plants from different natural populations and from tissue culture has been studied with blot-hybridization method. It was shown that ribosomal repeats are represented by the variants which differ for their size and for the presence of additional HindIII restriction site. Genome of individual plant usually possesses several variants of DNA repeats. Interpopulation variability according to their quantitative ratio and to the presence of some of them has been shown. Modifications of the range of rDNA repeats not exceeding intraspecific variability were observed in callus tissues in comparison with the plants of initial population. Non-randomness of genome modifications in the course of cell adaptation to in vitro conditions makes it possible to some extent to forecast these modifications in tissue culture. 相似文献
85.
A M Shamshinova T A Ivanina A A Yakovlev L P Shabalina V S Spiridonova 《Journal of hygiene, epidemiology, microbiology, and immunology》1990,34(2):113-121
Appearance of dystrophic alterations in the retina was carried out by administering 0.2 ml 12 mM of tallium chloride solution into the vitreous humour of 9 rabbits. Electroretinographic examination revealed a decline in the b wave either decreasing 2-3 times or entirely disappearing as early as on day 2 after the administration of tallium chloride. Electron microscopic investigation suggested that photoreceptors of the retina were initial by involved in the pathological process. Namely, the external segments of the photoreceptors were found to be reduced, indicating impairment of the formation of photoreceptor disks, which is known to proceed continuously under normal conditions. In the absence of an electroretinogram (ERG), the photoreceptor layers were shown to have disappeared completely. An examination of 28 subjects who were exposed to tallium and its compound at work revealed impaired retinal electrogenesis, as evident from subnormal ERG responses. This was of a functional nature and became more pronounced as occupational exposure time increased. The fact that the internal retinal layers and the 3-rd neurone remained intact, as suggested by the electrical sensitivity of the eye and lability of the optic nerve as well as by static perimetry, correlated with the EM findings obtained in experiments. Ophthalmobiomicroscopic examination of 12 eyes yielded data on characteristic changes in the lens when visual functions remained intact. These findings suggest that changes in the ERG may be indicative of initial preclinical symptoms of tallium intoxication and as such can be used when persons exposed to it in industry receive check-ups. 相似文献
86.
L. N. Spiridonova O. P. Valchuk Ya. A. Red’kin A. P. Kryukov 《Russian Journal of Genetics》2016,52(9):952-962
Sequence polymorphism of the mitochondrial DNA cytochrome b gene fragment was analyzed in 21 specimens of subspecies Luscinia calliope calliope (Pallas, 1776) and two specimens of L. c. anadyrensis (Portenko, 1939). On sequence chromatograms, in 19 specimens of L. c. calliope, double peaks of heteroplasmy type in the taxon-specific positions were revealed. Moreover, two clone variants were identified. The first variant was the calliope mitochondrial cyt b gene and the second was the nuclear cyt b pseudogene, similar to the mitochondrial haplotype anadyrensis-camtschatkensis. In L. c. anadyrensis, four clone variants, represented by the mitochondrial calliope and anadyrensis-camtschatkensis cyt b genes and nuclear calliope and sachalinensis cyt b pseudogenes, were identified. Some nuclear cyt b pseudogenes were highly similar (98–99%) to the mitochondrial genes of the subspecies L. c. anadyrensis, L. c. camtschatkensis, and L. c. sachalinensis. In the same time, the majority of nuclear pseudogene sequences were characterized by a high level of polymorphism, caused by nonsynonymous substitutions (up to five substitutions per sequence), the presence of indels in some of the clones, and TAA and TGA stop codons. In our opinion, the mitochondrial haplotypes anadyrensis-camtschatkensis and sachalinensis occurred as a result of intergenomic homologous recombination. This finding provides a new insight into the colonization history of the northeastern part of the range by L. calliope, according to which populating the territory of Chukotka, Kamchatka, and Sakhalin took place at different times and along the independent pathways. 相似文献
87.
88.
89.
The review considers the phylogeny and evolution of ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO), which is the
key enzyme of the autotrophic Calvin-Benson cycle and the most abundant protein on Earth. RuBisCO occurs in several structural
and functional forms, including fully functional forms I, II, and III, which catalyze carboxylation/oxygenation of ribulose
1,5-bisphosphate, and RuBisCO-like form IV, which lacks carboxylating activity. The genomic localization, operon structure,
and copy number of the RuBisCO genes vary among different autotrophic organisms. The RuBisCO gene phylogeny substantially
differs from the phylogeny of other conserved genes, including the 16S rRNA gene. The difference is due to duplication/deletion
and horizontal gene transfer events that were common in the evolution of autotrophic organisms. 相似文献
90.
Tiana Baqueiro Momtchilo Russo Virgínia MG Silva Thayna Meirelles Pablo RS Oliveira Eliane Gomes Renato Barboza Ana T Cerqueira-Lima Camila A Figueiredo Lain Pontes-de-Carvalho Neuza M Alcantara-Neves 《Respiratory research》2010,11(1):51