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981.
982.
Veselova MA Lipasova VA Zaĭtseva IuV Koksharova OA Chernukha MIu Romanova IuM Khmel' IA 《Genetika》2012,48(5):608-616
By means of plasposon mutagenesis, mutants of Burkholderia cenocepacia 370 with the change in production of N-acyl-homoserine lactones (AHL), signal molecules of the Quorum Sensing system of regulation, were obtained. To localize plasposon insertions in mutant strains, fragments of chromosomal DNA containing plasposons were cloned, adjacent DNA regions sequenced, and a search for homologous nucleotide sequences in the GeneBank was initiated. It has been shown that the insertion of plasposon into gene lon encoding lon proteinase drastically decreases AHL synthesis. Upon insertion of plasposon into gene pps encoding phosphoenolpyruvate-synthase, enhancement of AHL production is observed. In mutant carrying inactivated gene lon, a strong decline of extracellular protease activity, hemolytic, and chitinolytic activities was observed in comparison with the original strain; lipase activity was not changed in this mutant. Mutation in gene pps did not affect these properties of B. cenocepacia 370. Mutations in genes lon and pps reduced the virulence of bacteria upon infection of mice. 相似文献
983.
Differential C-banding and in situ hybridization were employed in a cytogenetic comparison of thee N-genome Aegilops species: diploid Ae. uniaristata, tetraploid Ae. ventricosa, and hexaploid Ae. recta. The formation of Ae. recta was shown to involve only minor functional modifications of the parental genomes, while intraspecific divergence was accompanied by large genome rearrangements, namely, translocations involving the total chromosome arms of all of the three genomes. The formation of tetraploid Ae. ventricosa involved substantial structural chromosome rearrangements, including a partial deletion of the short arm of chromosome 5D, including the nucleolus-organizing region; a redistribution of C bands on chromosomes of the D and N genomes along with a reduction of the heterochromatin content; and a considerable decrease in the hybridization intensity of the pAs1 repeat. Chromosomes of the Ae. ventricosa D genome were more similar to chromosomes of the Ae. crassa D1 genome than to Ae. tauschii chromosomes. 相似文献
984.
We have analyzed genetic effects of heterologous plant genes insertion on genome functioning of higher plants, belonging to different systematic groups (tobacco, Arabidopsis). Plants of different species were responding differently to the insertion of the same transgene, which is likely to be associated with the location of alien DNA insertion and could manifest in morphological changes spectrum and target gene expression level. 相似文献
985.
The character of chromosome pairing in meiocytes was studied in F1 wheat-rye Triticum aestivum L. x Secale cereale L. (ABDR, 4x = 28) hybrids with three types of chromosome behavior: reductional, equational, and equational + reductional. A high variation of the frequencies of bivalents and ring univalents was observed in meiocytes with the reductional or equational + reductional type of chromosome behavior. The type of chromosome division was found to affect the bivalent and ring univalent frequencies. Chromosome pairing occurred in 10.28% of meiocytes with the reductional chromosome behavior, 0.93% of meiocytes with the equational chromosome behavior, and 10.81% of meiocytes with the equational + reductional chromosome behavior. On average, 0.13 bivalents per cell formed in meiocytes of the hybrid population. C-banding and genomic in situ hybridization (GISH) showed that both rye and wheat chromosomes produced ring univalents. The role of the Ph genes in regulating the bivalent formation in meiocytes with different types of chromosome behavior is discussed. 相似文献
986.
Andrianov BV Sorokina SIu Lazebniĭ OE Goryacheva II Gorelova TV Kashtanov SN 《Genetika》2012,48(4):529-541
The first comparison of mitochondrial variations in sables from captive and natural populations of the Urals, Central Siberia, Yakutia, Kamchatka, and Japan has been performed. The object of comparative analysis was a 427-bp 5' fragment of the mitochondrial control region, including the D-loop. Two main haplogroups of the sable mitochondrial genome have been found, which provides new data for reconstruction of the spread of the sable over its current range. Asymmetry of the haplotype abundances in the captive populations of sables has been detected. The mitochondrial haplotypes characteristic of sable breeds have been identified. The possible role of the frequent mitochondrial haplotypes of the captive population in the sable adaptation to the conditions of captivity is discussed. 相似文献
987.
This paper presents results on anaerobic degradation of the azo dye blue HFRL in a bench scale Upflow anaerobic sludge blanket
(UASB) reactor operated at ambient temperature. The results show that the addition of yeast extract (500 mg/L) increased color
removal (P < 0.05) from 62 to 93% despite the low chemical oxygen demand (COD) removal (~35%) which happened due to volatile fatty acids
(VFA) accumulation. There were no differences in color removal (~91%) when yeast extract (500 mg/L) was used in the presence
or absence of glucose, suggesting that yeast extract acted as source of redox mediator (riboflavin) and carbon. The specific
rate of dye removal increased along the operational phases and depended on the presence of yeast extract, suggesting progressive
biomass acclimatization. Analysis of bacterial diversity by Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis
(PCR–DGGE) method showed there was biomass selection along the bioreactor operation and no evidence of azo dye degrading bacteria
predominance. This strengthens the hypothesis that color removal happens extracellularly by the reduction of azo bond by reduced
redox mediators, such as riboflavin, which is present in high amount in the yeast extract. 相似文献
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