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151.
S. Aswanikumar A.N. Radhakrishnan 《Biochimica et Biophysica Acta (BBA)/General Subjects》1973,304(1):210-216
The developmental pattern in experimental rat granuloma tissue and the distribution in the tissues of a few animals (monkey, rabbit, guinea pig anrat) of a peptidase acting on a synthetic collagenase substrate, 4-phenylazobenzyloxycarbonyl-L-Pro-L-Leu-Gly-L-Pro-D-Arg (Pz-peptide) has been studied. Maximum enzyme activity was found in 4-month-old rats and on the fourth day of implantation of the cotton wick. Pz-peptidase appears to have a ubiquitous distribution in animal tissues; the highest enzyme activity was generally found in liver, intestine and kidney of the animals. The total activity in other organs (spleen, heart, lungs and brain) was much less compared to that of liver, intestine or kidney. 相似文献
152.
Isolation of a peroxidatically active product from the peptic digest of ox-liver catalase and some of its properties 总被引:1,自引:1,他引:0
1. A homogeneous peroxidatically active product has been isolated from a peptic digest of ox-liver catalase. 2. The nitrogen and the iron contents of the ;active product' are 15.3% and 0.21% respectively. 3. The S(0) (20,w) and molecular weight of the ;active product' are 2.6s and 27500 respectively. 4. The ;active product' contains 248 amino acid residues/mol. assuming a mol.wt. of 27500. 5. The properties of the ;active product' and catalase are compared and the relationship between their structures and enzyme activity is discussed. 相似文献
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A highly antagonistic Pseudomonas fluorescens strain was isolated from tomato rhizosphere and characterized for its in vitro and in vivo biocontrol potential against Pythium aphanidermatum. The identified Pseudomonas fluorescens strain (PfT-8) was capable of producing high levels of chitinase, β-1,3-glucanase, cellulase, fungitoxic metabolites and
siderophores. Seven different carrier formulations including a talc-based powder, lignite-based powder, peat-based powder,
lignite + fly ash-based powder, wettable powder, bentonite-paste and polyethylene glycol (PEG) paste were prepared utilizing
PfT-8. Shelf life was evaluated for up to 6 months of storage at ambient room temperature (28 °C). Biocontrol efficacy of
formulations was studied under greenhouse and field conditions. The formulations were stable up to at least 2 months of storage
at ambient room temperature. Among the formulations, peat, lignite, lignite+fly-ash and bentonite paste based formulations
maintained higher propagule number than others and also showed greater biocontrol potential. However, propagule number gradually
decreased with time. Several organic amendments including farm yard manure (FYM), leaf-compost, poultry manure, press mud,
vermi-compost and neem cake were incorporated into soil to study their influence on P. fluorescens colonization in the rhizosphere and on potential disease control. Soil incorporation of organic amendments and specifically
poultry manure and FYM, significantly reduced damping-off incidence and also augmented the rhizosphere population of the marked␣P.␣fluorescens strain that was resistant to streptomycin and rifampicin. An integrated␣approach of damping-off management employing dual
inoculation of PfT-8 in seed and soil coupled with soil application of organic amendments including poultry manure or␣FYM
was evaluated under field conditions. Under these conditions, damping-off incidence substantially reduced by up to 90% and
further the healthy plant stand, plant biomass and plant rhizosphere population of P. fluorescens increased significantly. 相似文献
157.
Diana Pérez-Staples Christopher W. Weldon Preethi Radhakrishnan John Prenter 《Journal of insect physiology》2010,56(12):1755-1762
Copula duration and sperm storage patterns can directly or indirectly affect fitness of male and female insects. Although both sexes have an interest in the outcome, research has tended to focus on males. To investigate female influences, we compared copula duration and sperm storage of Queensland fruit fly females that were intact, or had been incapacitated through decapitation or abdomen isolation. We found that copulations were far longer when females had been incapacitated, indicating that constraints imposed on copula duration by intact females had been relaxed. Repeatability of copula duration for males was very low regardless of female treatment, and this is also consistent with strong female influence. Number of sperm in the spermathecae was not influenced by female treatment, suggesting that female abdominal ganglia control the transport of sperm to these long-term storage organs. However, more sperm were found in the ventral receptacles of incapacitated females compared to intact females. Overall, results implicate cephalic ganglia in regulation of copula duration and short-term sperm storage in the ventral receptacle and abdominal ganglia in regulation of long-term sperm storage in the spermathecae. 相似文献
158.
There is overwhelming evidence that lipid bilayer regions of animal cell membranes are in a liquid state. Quantitative models of these bilayer regions must then be models of liquids. These liquids are highly non-ideal. For example, it has been known for more than 75 years that mixtures of cholesterol and certain phospholipids undergo an area contraction or condensation in lipid monolayers at the air-water interface. In the past 3 years, a thermodynamic model of “condensed complexes” has been proposed to account for this non-ideal behavior. Here we give an overview of the model, its relation to other models, and to modern views of the properties of animal cell membranes. 相似文献
159.
Thomas Dierks Lars Schlotawa Marc-André Frese Karthikeyan Radhakrishnan Kurt von Figura Bernhard Schmidt 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2009,1793(4):710-725
Multiple sulfatase deficiency (MSD), mucolipidosis (ML) II/III and Niemann–Pick type C1 (NPC1) disease are rare but fatal lysosomal storage disorders caused by the genetic defect of non-lysosomal proteins. The NPC1 protein mainly localizes to late endosomes and is essential for cholesterol redistribution from endocytosed LDL to cellular membranes. NPC1 deficiency leads to lysosomal accumulation of a broad range of lipids. The precise functional mechanism of this membrane protein, however, remains puzzling. ML II, also termed I cell disease, and the less severe ML III result from deficiencies of the Golgi enzyme N-acetylglucosamine 1-phosphotransferase leading to a global defect of lysosome biogenesis. In patient cells, newly synthesized lysosomal proteins are not equipped with the critical lysosomal trafficking marker mannose 6-phosphate, thus escaping from lysosomal sorting at the trans Golgi network. MSD affects the entire sulfatase family, at least seven members of which are lysosomal enzymes that are specifically involved in the degradation of sulfated glycosaminoglycans, sulfolipids or other sulfated molecules. The combined deficiencies of all sulfatases result from a defective post-translational modification by the ER-localized formylglycine-generating enzyme (FGE), which oxidizes a specific cysteine residue to formylglycine, the catalytic residue enabling a unique mechanism of sulfate ester hydrolysis. This review gives an update on the molecular bases of these enigmatic diseases, which have been challenging researchers since many decades and so far led to a number of surprising findings that give deeper insight into both the cell biology and the pathobiochemistry underlying these complex disorders. In case of MSD, considerable progress has been made in recent years towards an understanding of disease-causing FGE mutations. First approaches to link molecular parameters with clinical manifestation have been described and even therapeutical options have been addressed. Further, the discovery of FGE as an essential sulfatase activating enzyme has considerable impact on enzyme replacement or gene therapy of lysosomal storage disorders caused by single sulfatase deficiencies. 相似文献
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