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81.
The present investigation analyzes the in vitro P solubilization [Ca-P, Al-P, Fe(II)-P, and Fe(III)-P] efficiency of native PSB strains from acid soils of Odisha and exploitation of the same through biofertilization in peanut (Arachis hypogaea L.) growth and P acquisition. One hundred six numbers of soil samples with pH ≤ 5.50 were collected from five districts of Odisha viz., Balasore, Cuttack, Khordha, Keonjhar, and Mayurbhanj. One bacterial isolate from each district were selected and analyzed for their P solubilization efficiency in National Botanical Research Institute Phosphate broths with Ca, Al, and Fe-complexed phosphates. CTC12 and KHD08 transformed more amount of soluble P from Ca-P (CTC12 393.30 mg/L; KHD08 465.25 mg/L), Al-P (CTC12 40.00 mg/L; KHD08 34.50 mg/L), Fe(III)-P (CTC12 175.50 mg/L; KHD08 168.75 mg/L), and Fe(II)-P (CTC12 47.40 mg/L; KHD08 42.00 mg/L) after 8 days of incubation. The bioconversion of P by all the five strains in the broth medium followed the order Ca-P > Fe(III)-P > Fe(II)-P > Al-P. The identified five strains were Bacillus cereus BLS18 (KT582541), Bacillus amyloliquefaciens CTC12 (KT633845), Burkholderia cepacia KHD08 (KT717633), B. cepacia KJR03 (KT717634), and B. cepacia K1 (KM030037) and further studied for biofertilization effects on peanut. CTC12 and KHD08 enhanced the soil available P around 65 and 58% and reduced the amount of each Al3+ about 79 and 81%, respectively, over the uninoculated control pots in the peanut rhizosphere. Moreover, all tested PSB strains could be able to successfully mobilize P from inorganic P fractions (non-occluded Al-P and Fe-P). The strains CTC12 and KHD08 increased the pod yield (114 and 113%), shoot P (92 and 94%), and kernel P (100 and 101%), respectively, over the control. However, B. amyloliquefaciens CTC12 and B. cepacia KHD08 proved to be the potent P solubilizers in promoting peanut growth and yield.  相似文献   
82.
Glutamate decarboxylase: computer studies of enzyme evolution   总被引:2,自引:0,他引:2  
The homology of subunit primary sequence of 40 glutamate decarboxylases (GAD) of different origin was analyzed by multiple alignment. A phylogenetic tree was designed on the basis of the resulting data. The following groups are distinguished in the consensus tree: archeans, bacteria, plant eukaryotes, and animal eukaryotes. The latter are clearly divided into two branches according to two enzyme isoforms. Borders of PLP domains in each enzyme were detected. The consensus phylogenetic tree for PLP domains is structurally rather similar to that obtained for subunits. Twenty homologous motifs of from 15 to 87 amino acid residues were revealed in all GAD studied. The results revealed the division of all of the enzymes into groups with characteristic sets of motifs in each and a fixed order of their arrangement along the sequence. Thus, we can show the divergent evolution of the enzyme. The results of multiple alignments during structural analysis of the 40 GAD confirmed and extended our previous data on conserved residues that arrange the position of the coenzyme (PLP) in the enzyme active center. The following residues should be noted: lysine forming a Schiff base with the PLP aldehyde group, an adjacent histidine, and aspartic acid that establishes a link with nitrogen of the PLP pyridine ring. The homology of the primary sequence fragments was also found in the residues in contact with the PLP phosphate group. Comparison of the GAD amino acid sequence with that of another PLP enzyme, aspartate aminotransferase, revealed a binding site for carboxylic group of the substrate—glutamic acid. The structures carrying out a particular catalytic function of all GAD studied were detected, i.e., convergent evolution of the enzyme was revealed.  相似文献   
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The allele and genotype frequency distributions of the D11S2008 tetranucleotide microsatellite linked with the catalase (CAT) gene were compared between patients with insulin-dependent diabetes mellitus (IDDM) with (N = 72) and without (N = 82) coronary heart disease (CHD), and between IDDM patients with normal arterial tension (N = 82) and with arterial hypertension (N = 42). In total, eight alleles were found. The alleles varied in length from 120 to 148 bp and included from 15 to 22 tetranucleotide repeats. The groups did not differ in D11S2008 allele and genotype frequencies; the only exception was that the frequency of genotype 18/19 in patients with CHD (31.9%) was significantly higher than in the controls (18.3%). Thus, the D11S2008 polymorphic locus located in proximity to the catalase gene proved to be weakly associated with CHD, but not associated with arterial hypertension, in IDDM patients. Genotype 18/19 was associated with a higher risk of CHD.  相似文献   
85.
To study the contribution of the catalase (CAT) gene in diabetes mellitus (DM) type 2, the allele and genotype frequencies of internal (polymorphism C1167T) and two neighboring (minisatellites D11S907 and D11S2008) polymorphic markers were studied in 132 healthy individuals and 154 patients from Moscow. Allele C and genotype CC of the C1167T polymorphism proved associated with a higher risk of DM type 2. Seven D11S907 alleles containing 14 to 20 dinucleotide repeats were found. The frequencies of alleles 15 and 16 and genotype 18/20 were significantly higher and those of allele 18 and genotypes 17/18 and 18/19 were lower in patients than in controls. Eight D11S2008 alleles containing 15 to 22 tetranucleotide repeats were found. The frequencies of alleles 17 and 18 and genotype 18/20 in patients were significantly higher than in controls. An association of the three polymorphic loci and DM type 2 was suggested.  相似文献   
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89.
A suspension subline LS of mouse fibroblasts L was adapted to the growth in monolayer (LSM subline). The duration of cell cycle and its phases was determined for both the sublines synchronized by a double thymidine block. The duration of cell cycle for LS cells is 17.0 hours, with G1, S and G2 + M being 8.8, 6.3 and 1.8 hours, resp., for LSM cells corresponding values being 31.6, 15.6, 11.0 and 4.8 hours. The karyotype of LSM cells differs from that of LS cells only slightly: there is a redistribution between the numbers of cells with 55 and 56 chromosomes, and a decrease in the number of polyploid cells from 2.0 till 0.2%. The data obtained indicate the heterogeneity of the L line culture which contains cells with long and short cycles. Depending on the mode of cultivation (suspension or monolayer), there is a certain predominance of population either with short or with long cell cycle.  相似文献   
90.
Plant–virus interactions are greatly influenced by environmental factors such as temperatures. In virus-infected plants, enhanced temperature is frequently associated with more severe symptoms and higher virus content. However, the mechanisms involved in such regulatory effects remain largely uncharacterized. To provide more insight into the mechanisms whereby temperature regulates plant–virus interactions, we analysed changes in the proteome of potato cv. Chicago plants infected with potato virus Y (PVY) at normal (22 °C) and elevated temperature (28 °C), which is known to significantly increase plant susceptibility to the virus. One of the most intriguing findings is that the main enzymes of the methionine cycle (MTC) were down-regulated at the higher but not at normal temperatures. With good agreement, we found that higher temperature conditions triggered consistent and concerted changes in the level of MTC metabolites, suggesting that the enhanced susceptibility of potato plants to PVY at 28 °C may at least be partially orchestrated by the down-regulation of MTC enzymes and concomitant cycle perturbation. In line with this, foliar treatment of these plants with methionine restored accumulation of MTC metabolites and subverted the susceptibility to PVY at elevated temperature. These data are discussed in the context of the major function of the MTC in transmethylation processes.  相似文献   
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