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排序方式: 共有163条查询结果,搜索用时 31 毫秒
31.
Syed Mohsin Bukhari Huda Ahmed Alghamdi Khalil Ur Rehman Shahla Andleeb Shahbaz Ahmad Nimra Khalid 《Saudi Journal of Biological Sciences》2022,29(3):1781-1788
Pheasant reintroduction and conservation efforts have been in place in Pakistan since the 1980 s, yet there is still a scarcity of data on pheasant microbiome and zoonosis. Instead of growing vast numbers of bacteria in the laboratory, to investigate the fecal microbiome, pheasants (green and ring neck pheasant) were analyzed using 16S rRNA metagenomics and using IonS5TMXL sequencing from two flocks more than 10 birds. Operational taxonomic unit (OTU) cluster analysis and phylogenetic tree analysis was performed using Mothur software against the SSUrRNA database of SILVA and the MUSCLE (Version 3.8.31) software. Results of the analysis showed that firmicutes were the most abundant phylum among the top ten phyla, in both pheasant species, followed by other phyla such as actinobacteria and proteobacteria in ring necked pheasant and bacteroidetes in green necked pheasant. Bacillus was the most relatively abundant genus in both pheasants followed by Oceanobacillus and Teribacillus for ring necked pheasant and Lactobacillus for green necked pheasant. Because of their well-known beneficial characteristics, these genus warrants special attention. Bird droppings comprise germs from the urinary system, gut, and reproductive sites, making it difficult to research each anatomical site at the same time. We conclude that metagenomic analysis and classification provides baseline information of the pheasant fecal microbiome that plays a role in disease and health. 相似文献
32.
Bovine kidney aldose reductase (ALR2) displays substrate inhibition by aldehyde substrates that is uncompetitive versus NADPH when allowance is made for nonenzymic reaction of the aldehyde with the adenine moiety of NADPH. A time-dependent increase in substrate inhibition observed in product versus time plots for reduction of short-chain aldoses containing an enolizable alpha-proton, but not for p-nitrobenzaldehyde, is shown to be consistent with a model in which rapidly reversible inhibition due to formation of the dead-end E-NADP-glycolaldehyde complex is combined with the formation at the enzyme active site of a tightly-bound covalent NADP-glycolaldehyde adduct. Quantitative analysis of reaction time courses for ALR2-catalyzed reduction of glycolaldehyde using NADPH or the 3-acetylpyridine analogue, (AP)ADPH, yields values of the forward and reverse rate constants for ALR2-mediated adduct formation that agree with the values determined in the absence of glycolaldehyde turnover. Substrate inhibition is only partial, indicating that reaction can occur via an alternate pathway at high [glycolaldehyde]. Kinetic evidence for a slow isomerization of the E-NADP complex at pH 8.0 is used to explain the similar V/Et values observed for glycolaldehyde reduction at pH 7.0 using NADPH, (AP)ADPH, and the hypoxanthine analogue N(Hx)DPH. The practical implications of these results for kinetics studies of aldose reductase are discussed. 相似文献
33.
M. Shahbaz C. E. E. Stuiver F. S. Posthumus S. Parmar M. J. Hawkesford L. J. De Kok 《Plant biology (Stuttgart, Germany)》2014,16(1):68-78
The toxicity of high copper (Cu) concentrations in the root environment of Chinese cabbage (Brassica pekinensis) was little influenced by the sulphur nutritional status of the plant. However, Cu toxicity removed the correlation between sulphur metabolism‐related gene expression and the suggested regulatory metabolites. At high tissue Cu levels, there was no relation between sulphur metabolite levels viz. total sulphur, sulphate and water‐soluble non‐protein thiols, and the expression and activity of sulphate transporters and expression of APS reductase under sulphate‐sufficient or‐deprived conditions, in the presence or absence of H2S. This indicated that the regulatory signal transduction pathway of sulphate transporters was overruled or by‐passed upon exposure to elevated Cu concentrations. 相似文献
34.
Farrukh I. S.; Michael J. R.; Summer W. R.; Adkinson N. F. Jr; Gurtner G. H. 《Journal of applied physiology》1985,58(1):34-44
Infusion of tert-butyl hydroperoxide (t-bu-OOH) or arachidonic acid into rabbit pulmonary arteries stimulated thromboxane B2 (TxB2) production and caused pulmonary vasoconstriction. Both phenomena were blocked by cyclooxygenase inhibitors or a thromboxane synthase inhibitor. The increase in pulmonary arterial pressure caused by either t-bu-OOH or arachidonic acid infusion correlated with the concentration of TxB2 in the effluent perfusate. The concentration of TxB2 in the effluent perfusate, however, was always 10-fold greater after arachidonic acid infusion. In the rabbit pulmonary vascular bed lipoxygenase products did not appear involved in the vasoactive response to t-bu-OOH or exogenous arachidonic acid infusion. Calcium entry blockers or a calcium-free perfusate prevented the thromboxane-induced pulmonary vasoconstriction. Calmodulin inhibitors also blocked the pulmonary vasoconstriction induced by t-bu-OOH without affecting the production of TxB2 or prostacyclin. These results suggest that thromboxane causes pulmonary vasoconstriction by increasing cytosol calcium concentration. 相似文献
35.
Rufus Vinod Munawar Samuel Syeda Yumna Farrukh Sadia Rehmat Muhammad Umair Hanif Syed Shoaib Ahmed Syed Ghulam Musharraf Faiza Gul Durrani Mahjabeen Saleem Roquyya Gul 《Molecular biotechnology》2018,60(8):585-594
Human recombinant vascular endothelial growth factor-A121 (hrVEGF-A121) has applications in pharmaceutical industry especially in regenerative medicine. Here, we report the expression, purification, and characterization of hrVEGF-A121 in Escherichia coli expression system using human small ubiquitin-related modifier-3 (hSUMO3) fusion partner. Total RNA was isolated from healthy human gingival tissue, VEGF-A121 gene was RT-PCR amplified, and hSUMO3 gene was tagged at N-terminus. The fusion gene (SUMO3-VEGF-A121) was cloned in pET-22b(+) expression vector and transferred into E. coli strains; BL21 codon?+?and Rosetta-gami B(DE3). The hrVEGF-A121 expression was optimized for temperature, IPTG concentration, and time in Terrific Broth (TB). The positive transformants were sequenced and hrVEGF-A121 nucleotide sequence was submitted to Genbank (Accession No. KT581010). Approximately 40% of total cell protein expression was observed in soluble form on 15% SDS-PAGE. The hSUMO3 was cleaved from hrVEGF-A121 with SUMO protease and purified by Fast Protein Liquid Chromatography using anionic Hi-trap Resource Q column. From 100 ml TB, ~?25.5% and ~?6.8 mg of hrVEGF-A121 protein was recovered. The dimerized hrVEGF-A121 was characterized by Native PAGE and Western blot, using human anti-VEGF-A antibody and ESI-MS showed dimeric hrVEGF-A121 at 31,015 Da. The biological activity of hrVEGF-A121 was assessed in vitro by MTT and cell viability assay and observed to be bioactive. 相似文献
36.
Nadil Shah Sumera Anwar Jingjing Xu Zhaoke Hou Akram Salah Shahbaz Khan Jianfang Gong Zhengwei Shang Li Qian Chunyu Zhang 《Biotechnology letters》2018,40(8):1159-1165
Salt stress is considered one of the main abiotic factors to limit crop growth and productivity by affecting morpho-physiological and biochemical processes. Genetically, a number of salt tolerant Brassica varieties have been developed and introduced, but breeding of such varieties is time consuming. Therefore, current focus is on transgenic technology, which plays an important role in the development of salt tolerant varieties. Various salt tolerant genes have been characterized and incorporated into Brassica. Therefore, such genetic transformation of Brassica species is a significant step for improvement of crops, as well as conferring salt stress resistance qualities to Brassica species. Complete genome sequencing has made the task of genetically transforming Brassica species easier, by identifying desired candidate genes. The present review discusses relevant information about the principles which should be employed to develop transgenic Brassica species, and also will recommend tools for improved tolerance to salinity. 相似文献
37.
Abstract The role of immune serum in the engulfment of Listeria monocytogenes by polymorphonuclear leukocytes (PMNLs) of rabbits was documented employing an in vitro assay. Three serovarieties of L. monocytogenes , viz. serovars 1/2a, 4a and 4b, were separately incubated with PMNLs of nonimmune rabbit and high titre homologous or heterologous antisera. Normal rabbit serum was used as control. The number of L. monocytogenes per neutrophil was counted in stained smears in each assay and opsonic indices were calculated. Higher opsonic indices, i.e. 2.50, 2.09 and 2.56, for the three strains respectively, were obtained when bacteria were engulfed in the presence of homologous antisera as compared to when the bacterial cells were incubated with heterologous antisera, opsonic indices being in the range of 0.87 to 1.63. These results are indicative of a possible role of specific serum factors in at least the internalization of L. monocytogenes by PMNLs of rabbits and therefore in the host defenses against Listerial infections. 相似文献
38.
Structural studies and isolation of cDNA clones providing the complete sequence of rat liver dihydropteridine reductase 总被引:4,自引:0,他引:4
M Shahbaz J A Hoch K A Trach J A Hural S Webber J M Whiteley 《The Journal of biological chemistry》1987,262(34):16412-16416
The cleavage of reductively alkylated rat liver dihydropteridine reductase with cyanogen bromide afforded a mixture of peptides, six of which (CB-1 to CB-6) were isolated and purified by C8 reverse-phase high performance liquid chromatography. Portions of peptides CB-1, CB-4, and CB-6 were sequenced by automated Edman degradation and high performance liquid chromatography and the carboxyl-terminal region by conventional procedures. Further proteolytic digestion of CB-6 and isolation of the products afforded a seven-amino acid peptide. A low degeneracy probe comprising 20 nucleotides was synthesized from the sequence of this peptide and was used to screen a rat liver cDNA expression library constructed in the vector lambda gt 10. Positive clones were isolated, and detailed examination of five of these by restriction endonucleases and dideoxy sequence analyses allowed identification of the entire coding region for dihydropteridine reductase. The gene was found to code for a protein of 240 amino acids (excluding the methionine initiator) of Mr = 25,420. Each of the sequences corresponding to the peptides CB-1, CB-4, CB-6, and the carboxyl terminus were identified in the deduced protein sequence. The rat enzyme is highly homologous to the human dihydropteridine reductase; the two proteins differ in only 10 amino acids, and all are conservative substitutions. In contrast, the sequence shows little homology with that of mammalian dihydrofolate reductase: reduced pyridine nucleotide-requiring enzymes with superficial mechanistic similarities. 相似文献
39.
Fungi including Aspergillus and Penicillium, resistant to Ni2+, Cd2+, and Cr6+ were isolated from soil receiving long-term application of municipal wastewater mix with untreated industrial effluents of Aligarh, India. Metal tolerance in term of minimum inhibitory concentration (MIC) was 125-550 microg/ml for Cd, 300-850 microg/ml for Ni and 300-600 microg/ml for Cr against test fungi. Two isolates, Aspergillus niger and Penicillium sp. were tested for their Cr, Ni and Cd biosorption potential using alkali treated, dried and powdered mycelium. Biosorption experiment was conducted in 100 ml of solution at three initial metal concentrations i.e., 2, 4 and 6 mM with contact time (18 hr) and pretreated fungal biomass (0.1g) at 25 degrees C. Biosorption of all metals was found higher at 4 mM initial metal concentration as compared to biosorption at 2 and 6 mM concentrations. At 4 mM initial metal concentration, chromium biosorption was 18.05 and 19.3 mg/g of Aspergillus and Penicillium biomasses, respectively. Similarly, biosorption of Cd and Ni ions was also maximum at 4 mM initial metal concentration by Aspergillus (19.4 mg/g for Cd and 25.05 mg/g of biomass for Ni) and Penicillium (18.6 mg/g for Cd and 17.9 mg/g of biomass for Ni). In general, biosorption of metal was influenced by initial metal concentration and type of the test fungi. The results indicated that fungi of metal contaminated soil have high level of metal tolerance and biosorption properties. 相似文献
40.
A survey was conducted with the aim to document the indigenous information of Charkotli Hills, Batkhela District, Malakand, Pakistan. The area has rich vegetation and a high potential for ethnobotanical utiliza-tion. Information was collected on various traditional uses of 100 plants distributed over 49 families, of which 43 families were of dicot, 2 of monocot, 2 of pteridophyta, and 1 of gymnosperms. Most plants have more than one local use. Sixty-six plants were found to be medicinal species, 21 fruit and edible seed species, 11 furniture species, 18 fodder or forage species, 12 vegetable species, 12 fuel species, 11 thatching and building species, 5 hedge or fencing species, 5 timber wood species, 5 poisonous plants, 3 species used in ketchup, 2 fixed oil yielding species, 2 miswak species, 2 species for making sticks for cattle and defense purposes, 2 species cultivated for ornamental purposes, 2 species used as mehindi by girls, 1 irritant species, 1 species for the making of Salai (a little stick for applying 'surma' to the eyes), 1 species for tanning, 1 species used as refresher in milk pots, 1 species giving gum used as chewing gum, and 1 species used as insect repellent. The area is under heavy pressure of deforestation and overgrazing, which have reduced the regeneration of woody plants. Proper ecological manage-ment is required to protect the wildlife and ethnobotanical resources for the coming generations. 相似文献