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51.
Rukhsana Nighat Shuja Shuja Uddin Ahmad Taimuri Farah Rauf Shakoori Abdul Rauf Shakoori 《Molecular biology reports》2013,40(12):7061-7068
Truncated recombinant metallothionein GST–fusion protein has been successfully expressed in Escherichia coli. The previously identified novel Cd-inducible metallothionein (TMCd1) gene from the locally isolated ciliate, Tetrahymena tropicalis lahorensis, was inserted into a pET-41a vector, in frame with a sequence encoding an N-terminal glutathione-S-transferase (GST) tail. Truncated recombinant GST fusion protein has been purified by affinity column chromatography using glutathione sepharose. After enzymatic cleavage of GST tail with enterokinase, the truncated TMCd1 MT shows molecular weight of 11.5 kDa, corresponding to the expected value. This is the first successful report of expression of cadmium metallothionein gene of a ciliate, T. t. lahorensis, reported from this part of the world, in E. coli. This study will further help in characterization of metallothionein protein of this ciliate. 相似文献
52.
Majida Atta Muhammad Samia Falak Naeem Rashid Qurra-tul-Ann Afza Gardner Nasir Ahmad Tadayuki Imanaka Muhammad Akhtar 《Biochemistry. Biokhimii?a》2017,82(7):821-825
Tk1884, an open reading frame encoding α-amylase in Thermococcus kodakarensis, was cloned with the native signal sequence and expressed in Escherichia coli. Heterologous gene expression resulted in secretion of the recombinant protein to the extracellular culture medium. Extracellular α-amylase activity gradually increased after induction. Tk1884 was purified from the extracellular medium, and its molecular mass determined by electrospray ionization mass spectrometry indicated the cleavage of a few amino acids. The N-terminal amino acid sequence of the purified Tk1884 was determined, which revealed that the signal peptide was cleaved between Ala26 and Ala27 by E. coli signal peptidase. To the best of our knowledge, this is the first report describing an archaeal signal sequence recognized and cleaved by E. coli signal peptidase. 相似文献
53.
Summary Field experiments were conducted to determine the effects of the amount, time and method of fertilizer N application on the
efficiency of N uptake, N2 fixatio and yield of soybean.
Soil and foliar fertilizer N, applied during the pod-filling stage were absorbed by plants with equal and high efficiency,
compared to an appreciably lower utilization efficiency for N applied before seedling emergence. These results reveal that
the soybean roots were active in N uptake during these late stages of growth. Nitrogen fertilization during pod-filling resulted
in significant yield increases over the control treatment which received an early application of 20 Kg N/ha. Seed yield increases
were, however, more pronounced than total dry matter yield, and virtually all of the late-applied N was translocated into
the pods. Nitrogen fixation in soybean was not influenced by the application of 40 kg N/ha to plants as soil or foliar N during
the pod-filling stage. However, 80 kg N/ha supplied during pod-filling as 40 kg soil plus 40 kg foliar N/ha significantly
reduced the amount of N2 fixed.
The results obtained in these studies suggest that inadequate N supply during pod-filling limited soybean yields, and that
by the judicious application of fertilizer N during the late stages of growth, it was possible to enhance soybean yields without
necessarily inhibiting N2 fixation. 相似文献
54.
Oleanolic acid has been isolated from chloroform extract of Olea ferruginea Royle after removal of organic bases and free acids. The literature survey revealed it to be biologically very important. In this review the biological significance of oleanolic acid and its derivatives has been discussed. The aim of this review is to update current knowledge on oleanolic acid and its natural and semisynthetic analogs, focussing on its cytotoxic, antitumer, antioxidant, anti-inflamatory, anti-HIV, acetyl cholinesterase, alpha-glucosidase, antimicrobial, hepatoprotective, anti-inflammatory, antipruritic, spasmolytic activity, anti-angiogenic, antiallergic, antiviral and immunomodulatory activities. We present in this review, for the first time, a compilation of the most relevant scientific papers and technical reports of the chemical, pre-clinical and clinical research on the properties of oleanolic acid and its derivatives. 相似文献
55.
56.
Siddiq F Fatima I Malik A Afza N Iqbal L Lateef M Hameed S Khan SW 《Chemistry & biodiversity》2012,9(1):91-98
New bergenin derivatives, bergecins A and B (1 and 2, resp.), have been isolated from the AcOEt-soluble fraction of Bergenia stracheyi, along with bergenin (3), and their structures were elucidated on the basis of (1) H- and (13) C-NMR spectra, and by COSY, HMQC, and HMBC experiments. Compound 2 showed potent inhibitory potential against the enzyme lipoxygenase, while 1 was moderately active. On the other hand, both compounds exhibited significant antioxidant activities in 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay. 相似文献
57.
Muhammad Waseem M. Amin Ullah Shah Rizwana Aleem Qureshi Iqbal Muhammad Rabia Afza Saeeda Yousaf 《云南植物研究》2006,28(5):535-542
IntroductionSudhan Gali is situated at about2100mabovesea level andlies between latitude34°3′35″-34°6′35″andlongitude73°44′30″-70°48′15″.It is60kmawayfromState Capital Muzaffarabad,Kashmir,Pakistan.The highest point of Sudhan Gali is Ganga Choti.Itsheight is about3045m,whichis famous for its fasci-natinglandscape.The soil of Sudhan Gali varies fromclay loamtosandyloamand calcareousin nature.Itis veryshallowon slopes and deep in valley floors.The area has ex-treme climate with… 相似文献
58.
First cadmium metallothionein like gene PMCd1 of a ciliate, Paramecium sp., isolated from industrial wastewater has been cloned and sequenced. PMCd1 is an intronless gene, encoding 612 nucleotides, with TAA coding for glutamine. The coding region of PMCd1 comprises 203 amino acids, including 37 cysteine residues with a conserved structural pattern in the form of recurring structural motifs, arranged in 17 x-cys-x-y-cys-x, 1 x-cys-cys-x and x-cys-x contexts. Both, the deduced amino acids and nucleotide sequence differ, not only from other animal metallothioneins (MTs), but also from the previously characterized Tetrahymena Cu and Cd-MTs. The translated protein of PMCd1 contains conserved cysteine residues, peculiar characteristic of stress inducible metallothionein genes of ciliates and other groups of organisms. 相似文献
59.
Goutami Banerjee Suzana Car John S. Scott‐Craig Melissa S. Borrusch Nighat Aslam Jonathan D. Walton 《Biotechnology and bioengineering》2010,106(5):707-720
The high cost of enzymes is a major bottleneck preventing the development of an economically viable lignocellulosic ethanol industry. Commercial enzyme cocktails for the conversion of plant biomass to fermentable sugars are complex mixtures containing more than 80 proteins of suboptimal activities and relative proportions. As a step toward the development of a more efficient enzyme cocktail for biomass conversion, we have developed a platform, called GENPLAT, that uses robotic liquid handling and statistically valid experimental design to analyze synthetic enzyme mixtures. Commercial enzymes (Accellerase 1000 +/? Multifect Xylanase, and Spezyme CP +/? Novozyme 188) were used to test the system and serve as comparative benchmarks. Using ammonia‐fiber expansion (AFEX) pretreated corn stover ground to 0.5 mm and a glucan loading of 0.2%, an enzyme loading of 15 mg protein/g glucan, and 48 h digestion at 50°C, commercial enzymes released 53% and 41% of the available glucose and xylose, respectively. Mixtures of three, five, and six pure enzymes of Trichoderma species, expressed in Pichia pastoris, were systematically optimized. Statistical models were developed for the optimization of glucose alone, xylose alone, and the average of glucose + xylose for two digestion durations, 24 and 48 h. The resulting models were statistically significant (P < 0.0001) and indicated an optimum composition for glucose release (values for optimized xylose release are in parentheses) of 29% (5%) cellobiohydrolase 1, 5% (14%) cellobiohydrolase 2, 25% (25%) endo‐β1,4‐glucanase 1, 14% (5%) β‐glucosidase, 22% (34%) endo‐β1,4‐xylanase 3, and 5% (17%) β‐xylosidase in 48 h at a protein loading of 15 mg/g glucan. Comparison of two AFEX‐treated corn stover preparations ground to different particle sizes indicated that particle size (100 vs. 500 µm) makes a large difference in total digestibility. The assay platform and the optimized “core” set together provide a starting point for the rapid testing and optimization of alternate core enzymes from other microbial and recombinant sources as well as for the testing of “accessory” proteins for development of superior enzyme mixtures for biomass conversion. Biotechnol. Bioeng. 2010;106: 707–720. © 2010 Wiley Periodicals, Inc. 相似文献
60.
Coal-smoke emissions of a thermal power plant affected the physio-chemical status of Peristrophe bicalyculata (Reth) Nees, as observed at the pre-flowering, flowering and post-flowering stages of plant growth. The nitrate level was
raised while nitrate reductase activity, and the soluble protein content of leaf declined heavily at the polluted site during
different stages of plant growth, compared to the control. The rate of photosynthesis also decreased under the pollution stress.
Sugar level in root, stem and leaves increased with growing age of the plant but was always lower at the polluted site than
at the reference site. In roots, the difference was marginal till flowering stage and quite conspicuous afterwards; stems
showed a reverse pattern of variation. Sulphur content was higher at the polluted site in all the organs and at each stage
of the plant life. The Zn and Fe concentrations were reduced in all plant parts under the pollution stress. Copper content
in root was consistently low at the polluted site. In the stem and leaves, however, it was almost equal on both the sites
at the pre-flowering stage but showed a wide difference during the later part of plant ontogeny. 相似文献