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51.
Crystallization of 5-aminolaevulinic acid dehydratase from Escherichia coli and Saccharomyces cerevisiae and preliminary X-ray characterization of the crystals. 总被引:1,自引:1,他引:0 下载免费PDF全文
P. T. Erskine N. Senior S. Maignan J. Cooper R. Lambert G. Lewis P. Spencer S. Awan M. Warren I. J. Tickle P. Thomas S. P. Wood P. M. Shoolingin-Jordan 《Protein science : a publication of the Protein Society》1997,6(8):1774-1776
5-Aminolaevulinic acid dehydratase (ALAD) catalyzes the formation of porphobilinogen from two molecules of 5-aminolaevulinic acid. Both Escherichia coli and Saccharomyces cerevisiae ALADs are homo-octameric enzymes which depend on Zn2+ for catalytic activity and are potently inhibited by lead ions. The E. coli enzyme crystallized in space group I422 (unit cell dimensions a = b = 130.7 A, c = 142.4 A). The best crystals were obtained in the presence of the covalently bound inhibitor laevulinic acid. The yeast enzyme (expressed in E. coli) crystallized in the same space group (I422) but with a smaller unit cell volume (a = b = 103.7 A, c = 167.7 A). High resolution synchrotron data sets were obtained from both E. coli and yeast ALAD crystals by cryocooling to 100 K. 相似文献
52.
Kashif Ali Khan Amna Shoaib Zoia Arshad Awan Abdul Basit Mujahaid Hussain 《Journal of Plant Interactions》2018,13(1):131-140
Mung bean [Vigna radiata (L.) Wilczek] is an important cash pulse crop extensively cultivated in the arid region of Pakistan, which encounters intimidating charcoal rot disease caused by Macrophomina phaseolina (Tassi) Goid. The current research was conducted to check the potential of Zn (1.25, 2.44 and 5?mg?kg?1) and FYM [farmyard manure (1% and 2%)] in mono-, bi- and trilateral interaction in managing disease and improving yield. Suppression of plant immunity by M. phaseolina was indicated by the change in activities of antioxidant enzymes (CAT and SOD) and cell wall strengthening enzymes (POX and PAL) that revealed inability of the protein receptor to identify the pathogen elicitor. FYM improved soil physicochemical properties and beneficial microbes activity, which released antimicrobial protein- and plant defense-stimulating protein and in response to ROS (reactive oxygen species) signaling molecules plant susceptibility was reduced. However, Zn as a co-factor chastened the ROS in stressed cells by upregulation of antioxidant enzymes in favor of the plant. The complex interaction of FYM and Zn potentially hijacked the further multiplication of pathogen. Finally, soil amendment improved biological attributes and grain yield to profitable farming in terms of harvest index percentage and benefit–cost ratio. 相似文献
53.
Muhammad Wasim Fazli Rabbi Awan Haq Nawaz Khan Abdul Tawab Mazhar Iqbal Hina Ayesha 《Biochemical genetics》2018,56(1-2):7-21
Inborn errors of metabolism (IEMs) are a group of inherited metabolic disorders which are caused by mutations in the specific genes that lead to impaired proteins or enzymes production. Different metabolic pathways are perturbed due to the deficiency or lack of enzymes. To date, more than 500 IEMs have been reported with most of them being untreatable. However, fortunately 91 such disorders are potentially treatable, if diagnosed at an earlier stage of life. IEMs have been classified into different categories and one class of IEMs, characterized by the physiological disturbances of amino acids is called as aminoacidopathies. Out of 91 treatable IEM, thirteen disorders are amino acid related. Aminoacidopathies can be detected by chromatography and mass spectrometry based analytical techniques (e.g., HPLC, GC–MS, LC–MS/MS) for amino acid level changes, and through genetic assays (e.g., PCR, TaqMan Genotyping, DNA sequencing) at the mutation level in the corresponding genes. Hence, this review is focused to describe thirteen common aminoacidopathies namely: Phenylketonuria (PKU), Maple Syrup Urine Disease (MSUD), Homocystinuria/Methylene Tetrahydrofolate Reductase (MTHFR) deficiency, Tyrosinemia type II, Citrullinemia type I and type II, Argininosuccinic aciduria, Carbamoyl Phosphate Synthetase I (CPS) deficiency, Argininemia (arginase deficiency), Hyperornithinemia–Hyperammonemia–Homocitrullinuria (HHH) syndrome, N-Acetylglutamate Synthase (NAGS) deficiency, Ornithine Transcarbamylase (OTC) deficiency, and Pyruvate Dehydrogenase (PDH) complex deficiency. Furthermore, the etiology, prevalence and commonly used analytical techniques for screening of aminoacidopathies are briefly described. This information would be helpful to researchers and clinicians especially from developing countries to initiate newborn screening programs for aminoacidopathies. 相似文献
54.
Various buffer management and congestion control mechanisms have been proposed to support differentiated Quality-of-Service
(QoS) requirements due to the heterogeneous properties of real-world network traffic and applications. Active Queue Management
(AQM) with multiple thresholds, which starts dropping packets before the queue becomes full in order to notify incipient stages
of congestion, is a promising buffer allocation mechanism. With the aim to capture the effects of heterogeneous traffic and
justify the choice of appropriate parameters, this paper develops an original analytical model for a finite buffer queueing
system with AQM under two heterogeneous classes of traffic which are modelled, respectively, by the non-bursty Poisson Process
and bursty Markov-Modulated Poisson Process (MMPP). We derive the aggregated and marginal performance metrics including the
mean queue length, response time, utilization, throughput, and loss probability. Extensive simulation experiments are used
to validate the accuracy of the analytical model. Furthermore the model is adopted to evaluate the performance of AQM with
heterogeneous traffic and under different working conditions.
相似文献
Irfan AwanEmail: |
55.
Mohammad Arif Awan Ferhat Abbas Masoom Yasinzai Robin A. J. Nicholas Shakeel Babar Roger D. Ayling Mohammad Adnan Attique Zafar Ahmed Abdul Wadood Faisal Ameer Khan 《Molecular biology reports》2010,37(7):3401-3406
Contagious caprine pleuropneumonia (CCPP) caused by Mycoplasma capricolum subspecies capripneumoniae (Mccp) is a disease of goats which causes high morbidity and mortality and is reported in many countries of the world. There are
probably no reports on the molecular prevalence of Mccp, Mycoplasma capricolum subsp. capricolum (Mcc) and Mycoplasma putrefaciens (Mp) in Balochistan and any other part of Pakistan. Thirty goats (n = 30) with marked respiratory symptoms were selected and procured from forty goat flocks in Pishin district of Balochistan
in 2008. The genomic deoxyribonucleic acid (DNA) from the lung samples (n = 30) of the slaughtered goats was purified and subjected to polymerase chain reaction (PCR) assays for the presence of Mycoplasma mycoides cluster members and Mp. The PCR-RFLP (restriction fragment length polymorphism) was also used to further confirm the Mccp. Of the thirty lung samples 17 (56.67%) were positive for the molecular prevalence of Mcc, Mccp and Mp. In total the molecular prevalence was observed as 17.65% for Mccp (n = 3), 70.59% for Mcc (n = 12) and 11.76% for Mp (n = 2). The RFLP profile has also validated the PCR results of Mccp by yielding two bands of 190 and 126 bp. The results of PCR-RFLP coupled with the presence of fibrinous pleuropneumonia and
pleurisy during postmortem of goats (n = 3) strongly indicated the prevalence of CCPP in this part of world. Moreover the prevalence of Mcc and Mp is also alarming in the study area. We report for the very first time the molecular prevalence of Mcc, Mccp, and Mp in the lung tissues of goats in the Pishin district of Balochistan, Pakistan. 相似文献
56.
Molecular Biology Reports - Angiotensin II (Ang II: a truncated octapeptide of angiotensinogen, AGT) and 11-β-hydroxylase influence regulation of blood pressure. Dysregulation of Ang II and... 相似文献
57.
The present study aimed to identify single-nucleotide polymorphism (SNP) in coding and non-coding regions of interleukin-6
(IL-6) gene of Pakistani sheep. The IL-6 gene of 205 animals from nine sheep breeds were sequenced for screening of SNP. Characterizing
the IL-6 gene revealed thirteen SNP sites within the intronic region of IL-6 gene. The novel SNPs found in the present study
can serve as genetic marker for association studies with susceptibility/resistance to parasite infection in sheep. This is
first report of SNP polymorphism of IL-6 gene of Pakistani sheep. 相似文献
58.
Imran Awan 《Ethnic and racial studies》2016,39(13):2425-2427
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60.
Chloroplast localization of Cry1Ac and Cry2A protein- an alternative way of insect control in cotton
Adnan Muzaffar Sarfraz Kiani Muhammad Azmat Ullah Khan Abdul Qayyum Rao Arfan Ali Mudassar Fareed Awan Adnan Iqbal Idrees Ahmad Nasir Ahmad Ali Shahid Tayyab Husnain 《Biological research》2015,48(1)