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11.
RasG protein accumulation occurs just prior to amoebae emergence during spore germination in Dictyostelium discoideum 总被引:1,自引:0,他引:1
Meenal Khosla George B. Spiegelman Gerald Weeks Todd W. Sands Kiran J. Virdy David A. Cotter 《FEMS microbiology letters》1994,117(3):293-298
Abstract RasG protein levels in dormant and germinating spores of Dictyostelium discoideum strains JC1 and SG1 were estimated by Western blotting. Ras Glevels were very low in dormant spores and remained low during the lag period, regardless of whether spores were heat activated or treated with autoactivator during the early stages of spore germination. RasG levels increased late during spore swelling just prior to the emergence stage of germination. These data are consistent with a requirement for RasG during vegetative growth. 相似文献
12.
Genetics of high level penicillin resistance in clinical isolates of Streptococcus pneumoniae 总被引:5,自引:0,他引:5
Victoria A Barcus Kiran Ghanekar Maggie Yeo Tracey J Coffey Christopher G Dowson 《FEMS microbiology letters》1995,126(3):299-303
Abstract Mosaic penicillin-binding proteins (PBP) 1A, 2X and 2B genes were cloned from four clinical isolates of Streptococcus pneumoniae with levels of susceptibility to penicillin ranging from 1.5 to 16 μg benzylpenicillin ml−1 . In each instance it was possible to transform either the penicillin-sensitive laboratory strain R6 or a sensitive clinical isolate 110K/70 to the full level of penicillin resistance with these three penicillin-binding proteins alone. Until now it has not been possible to clearly determine whether alterations to PBP1A, 2X and 2B alone were sufficient to attain high level penicillin resistance. 相似文献
13.
Usha K. Urs David J. Sharkey Thomas S. Peat Wayne A. Hendrickson H. M. Krishna Murthy 《Proteins》1995,23(1):111-114
Thermus aquaticus DNA polymerase I is an enzyme that is of both physiological and technological interest. It carries out template-directed polymerization of DNA at elevated temperatures and is widely used in polymerase chain reaction (PCR). We have obtained crystals of the enzyme that diffracts X-rays to at least 3.0 Å resolution in a cubic space group. Determination of the three-dimensional structure of the native enzyme along with those of relevant complexes will greatly enhance our knowledge of molecular events involved in DNA replication, will permit improvements in PCR, and will add to our knowledge of the structural bases of thermo stability in proteins. © 1995 Wiley-Liss, Inc. 相似文献
14.
Summary Hairy roots of Tagetes patula were grown for 24 days in modified Murashige and Skoog's liquid medium at different initial pH levels of 4.0, 5.0, 5.7, 6.0 and 7.0. Irrespective of the initial pH, after 12 days, the pH of the culture medium was approximately 4.5. However the final pH, after 24 days of growth, did depend weakly on the initial pH of the medium. The biomass yield was lowest at an initial pH of 4.0, possibly due to lower utilization of ammonium at this pH. Similar patterns of thiophene accumulation was observed at all pH levels tested. Maximum thiophene accumulation occurred in root cultures which were 12–16 days old.Abbreviations BBTOH
5-(4-hydroxy-1-butenyl)-2,2-bithienyl
- BBTOAc
5-(4-acetoxy-1-butenyl)-2,2-bithienyl
- BBT
5-(3-buten-1-ynyl)-2,2-bithienyl
- MS
Murashige and Skoog's nutrient medium
- B5
Gamborg's B5 nutrient salts
- HPLC
High pressure liquid chromatography 相似文献
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16.
Kiran J. Agarwal-Harding Michael H. Schwartz Scott L. Delp 《Journal of biomechanics》2010,43(8):1522-1526
Crouch gait, one of the most prevalent movement abnormalities among children with cerebral palsy, is frequently treated with surgical lengthening of the hamstrings. To assist in surgical planning many clinical centers use musculoskeletal modeling to help determine if a patient’s hamstrings are shorter or lengthen more slowly than during unimpaired gait. However, some subjects with crouch gait walk slowly, and gait speed may affect peak hamstring lengths and lengthening velocities. The purpose of this study was to evaluate the effects of walking speed on hamstrings lengths and velocities in a group of unimpaired subjects over a large range of speeds and to determine if evaluating subjects with crouch gait using speed matched controls alters subjects’ characterization as having “short” or “slow” hamstrings. We examined 39 unimpaired subjects who walked at five different speeds. These subjects served as speed-matched controls for comparison to 74 subjects with cerebral palsy who walked in crouch gait. Our analysis revealed that peak hamstrings length and peak lengthening velocity in unimpaired subjects increased significantly with increasing walking speed. Fewer subjects with cerebral palsy were categorized as having hamstrings that were “short” (31/74) or “slow” (38/74) using a speed-matched control protocol compared to a non-speed-matched protocol (35/74 “short”, 47/74 “slow”). Evaluation of patients with cerebral palsy using speed-matched controls alters and may improve selection of patients for hamstrings lengthening procedures. 相似文献
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18.
Ekambaram Padmini Munuswamy Usha Rani 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2010,151(2):187-193
Induction of antioxidant proteins like thioredoxin (Trx) and heat shock protein 90α (HSP90α) is a crucial step in the cellular response to oxidative stress. Here, we report the impact of environmental stress on Trx and HSP90α expressions in freshly isolated hepatocytes of Mugil cephalus living in either a contaminated (Test; Ennore) or uncontaminated (Control; Kovalam) estuary. Modulation in the activities of signal transduction molecules like apoptosis signal-regulating kinase 1 (ASK1) and c-Jun NH2-terminal kinase 1/2 (JNK1/2) were also investigated to understand their functional role under natural stressed condition. The expression pattern of the proteins was determined by immunoblotting and the relationship between the proteins was identified by regression analysis. Test fish hepatocytes demonstrated significant upregulation (P < 0.05) in the levels of Trx and HSP90α and insignificant inductions in the expression pattern of ASK1 and JNK1/2 than control fish hepatocytes. These findings provide direct evidence that Trx and HSP90α induction in fish hepatocytes under stress may aid cell survival by negatively regulating ASK1 expression and thereby functionally antagonizing the apoptotic role of JNK1/2 in natural aquatic systems. 相似文献
19.
Pankaj R. Nilkanth Sujit K. Ghorai Arulmozhi Sathiyanarayanan Kiran Dhawale Tansir Ahamad Manoj B. Gawande Sharad N. Shelke 《化学与生物多样性》2020,17(9)
A variety of 1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one azomethines and 1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one benzamide were prepared, characterized and evaluated for the anticonvulsant activity in the rat using picrotoxin‐induced seizure model. The prepared 1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one azomethine derivatives emerged potentially anticonvulsant molecular scaffolds exemplified by compounds, 7‐{(E)‐[(4‐nitrophenyl)methylidene]amino}‐5‐phenyl‐1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one, 7‐[(E)‐{[4‐(dimethylamino)phenyl]methylidene}amino]‐5‐phenyl‐1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one, 7‐{(E)‐[(4‐bromo‐2,6‐difluorophenyl)methylidene]amino}‐5‐phenyl‐1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one and 7‐[(E)‐{[3‐(4‐fluorophenyl)‐1‐phenyl‐1H‐pyrazol‐4‐yl]methylidene}amino]‐5‐phenyl‐1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one. All these four compounds have shown substantial decrease in the wet dog shake numbers and grade of convulsions with respect to the standard drug diazepam. The most active compound, 7‐[(E)‐{[4‐(dimethylamino)phenyl]methylidene}amino]‐5‐phenyl‐1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one, exhibited 74 % protection against convulsion which was higher than the standard drug diazepam. Furthermore, to identify the binding mode of the interaction amongst the target analogs and binding site of the benzodiazepine receptor, molecular docking study and molecular dynamic simulation were carried out. Additionally, in silico pharmacokinetic and toxicity predictions of target compounds were carried out using AdmetSAR tool. Results of ADMET studies suggest that the pharmacokinetic parameters of all the target compounds were within the acceptable range to become a potential drug candidate as antiepileptic agents. 相似文献
20.
Kiran Alluri 《Nucleosides, nucleotides & nucleic acids》2020,39(4):615-629
AbstractZinc homeostasis is maintained by 24 tissue-specific zinc transporters which include ZnTs (ZnT1-10), ZIPs (ZIP1-14), in addition to metallothionein (MT). Current study aimed the role of zinc transporters in maintaining the basal levels of zinc in functionally contrasting tissue specific THP-1 (monocyte), RD (muscle), and Saos-2 (bone) cells. Zinc transporters expression was assessed by qRT-PCR. The mRNA levels of ZnTs (ZnT5-7 & ZnT9), ZIPs (ZIP6-10, ZIP13-14), and MT were significantly (p?<?0.05) higher in Saos-2 compared to THP-1 and RD. The present study suggests that distinct expression pattern of zinc transporters and metallothionein might be responsible for the differential zinc assimilation. 相似文献