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221.
Hameeda B Harini G Rupela OP Kumar Rao JV Reddy G 《Indian journal of microbiology》2010,50(4):419-424
Two hundred and seven bacteria were isolated from composts and macrofauna and screened for plant growth promoting and antagonistic
traits. Seven of the 207 isolates showed antagonistic activity against Sclerotium rolfsii in plate culture. Inhibition of S. rolfsii by the bacterial isolates ranged between 61 and 84%. Two of the seven isolates were Bacillus sp. and rest belonged to Pseudomonas sp. Two isolates, Pseudomonas sp. CDB 35 and Pseudomonas sp. BWB 21 was compatible with chickpea Rhizobium sp. IC 59 and IC 76 in plate culture conditions. Increase in plant biomass (dry weight) ranged between 18 and 30% on application
of these bacteria by seed coating and seed priming methods. However, by seed-priming there was an increase in plant biomass
by 5–7% compared to seed coating. Number of nodules and the nodule weight was similar by both seed coating and seed priming
methods. Disease incidence was reduced up to 47% in treatments where captan (fungicide) or antagonistic Pseudomonas sp. CDB 35 was applied. Increase in shoot weight was 36% by seed coating with Rhizobium sp. IC 59 and Pseudomonas sp. CDB 35 when compared to captan application. Whereas by seed priming with IC 59 and CDB 35 increased shoot weight by 3
and 39% increase in nodulation was observed. 相似文献
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223.
Thangarajan Rajkumar Neelakantan Vijayalakshmi Gopisetty Gopal Kesavan Sabitha Sundersingh Shirley Uthandaraman M Raja Seshadri A Ramakrishnan 《Cancer cell international》2010,10(1):45
Background
Gastric cancer is one of the common cancers seen in south India. Unfortunately more than 90% are advanced by the time they report to a tertiary centre in the country. There is an urgent need to characterize these cancers and try to identify potential biomarkers and novel therapeutic targets. 相似文献224.
Tavarekere S. Girish Balasubramanian Gopal 《The Journal of biological chemistry》2010,285(38):29406-29415
Proteases belonging to the M20 family are characterized by diverse substrate specificity and participate in several metabolic pathways. The Staphylococcus aureus metallopeptidase, Sapep, is a member of the aminoacylase-I/M20 protein family. This protein is a Mn2+-dependent dipeptidase. The crystal structure of this protein in the Mn2+-bound form and in the open, metal-free state suggests that large interdomain movements could potentially regulate the activity of this enzyme. We note that the extended inactive conformation is stabilized by a disulfide bond in the vicinity of the active site. Although these cysteines, Cys155 and Cys178, are not active site residues, the reduced form of this enzyme is substantially more active as a dipeptidase. These findings acquire further relevance given a recent observation that this enzyme is only active in methicillin-resistant S. aureus. The structural and biochemical features of this enzyme provide a template for the design of novel methicillin-resistant S. aureus-specific therapeutics. 相似文献
225.
Swati Kittur Sambandam Sathyakumar Gopal Singh Rawat 《European Journal of Wildlife Research》2010,56(2):195-204
Livestock grazing and associated habitat degradation are considered as major reasons for declining populations of wild ungulates.
In the Himalaya, livestock grazing has been practiced for centuries. We studied the spatial and habitat use overlap between
the Himalayan tahr (Hemitragus jemlahicus) and domestic migratory livestock (Capra aegagrus hircus and Ovis aries) in the subalpine and alpine areas of the Kedarnath Wildlife Sanctuary, Uttarakhand, India, from April 2003 to March 2004
to investigate if there was an impact of livestock grazing on the habitat use of tahr in this area. Habitat parameters such
as altitude, aspect, slope, and vegetation cover used by the tahr and livestock were quantified and compared. Minimal spatial
overlap was observed. Tahr demonstrated preference for higher altitude and steeper terrain and occupied rocky terrain with
comparatively less grass, shrub, and tree cover, while livestock occupied lower slope categories with low rock cover and more
shrub and tree cover. Livestock used altitude, slope, and aspect categories in proportion to their availability. However,
the difference in use of altitude and slope was not significant, and an increase in the population of the tahr over the years
in the study area was concomitant to the decrease in the livestock use of the area, which raises doubts as to whether this
minimal habitat overlap is an outcome of spatial displacement or exclusion of the tahr from certain habitats. 相似文献
226.
Cell-penetrating peptides comprising cloned epitopes that contribute to membrane transduction, DNA-binding and cell targeting
functions are known to facilitate nucleic acid delivery. Using the ITASSER software, we predicted the 3-D structure of a well
characterized and efficient transfecting cell-penetrating peptide, namely TAT-Mu and its derivative TAT-Mu-AF protein that
harbors a targeting ligand, the HER2-binding affibody. Our model predicts TAT-Mu-AF fusion protein as primarily comprising
α-helices. The affibody in TAT-Mu-AF is predicted as a 3-helical domain that is distinct from the TAT-Mu domain. Its positioning
in three-dimensional structure is oriented in a manner that possibly favors interactions with receptor and facilitates transport
to the target site. The linker region between TAT-Mu and the affibody is also predicted as a helix that is likely to stabilize
the overall fold of the TAT-Mu-AF complex. Further, the evaluation of secondary structure of the designed TAT-Mu-AF fusion
protein by circular dichroism is in support of our predictions. 相似文献
227.
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229.
The significance of two interface arginine residues on the structural integrity of an obligatory dimeric enzyme thymidylate synthase (TS) from Lactobacillus casei was investigated by thermal and chemical denaturation. While the R178F mutant showed apparent stability to thermal denaturation by its decreased tendency to aggregate, the Tm of the R218K mutant was lowered by 5 degrees C. Equilibrium denaturation studies in guanidinium chloride (GdmCl) and urea indicate that in both the mutants, replacement of Arg residues results in more labile quaternary and tertiary interactions. Circular dichroism studies in aqueous buffer suggest that the protein interior in R218K may be less well-packed as compared to the wild type protein. The results emphasize that quaternary interactions may influence the stability of the tertiary fold of TS. The amino acid replacements also lead to notable alteration in the ability of the unfolding intermediate of TS to aggregate. The aggregated state of partially unfolded intermediate in the R178F mutant is stable over a narrower range of denaturant concentrations. In contrast, there is an exaggerated tendency on the part of R218K to aggregate in intermediate concentrations of the denaturant. The 3 A crystal structure of the R178F mutant reveals no major structural change as a consequence of amino acid substitution. The results may be rationalized in terms of mutational effects on both the folded and unfolded state of the protein. Site specific amino acid substitutions are useful in identifying specific regions of TS involved in association of non-native protein structures. 相似文献
230.