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121.
122.
Zafar Iqbal Khan Kafeel Ahmad Iqra Ashraf Sumaira Gondal Muhammad Sher Zafar Hayat Vito Laudadio Vincenzo Tufarelli 《Saudi Journal of Biological Sciences》2015,22(3):249-255
The present study aimed to evaluate the bioaccumulation of some macrominerals in grazing buffaloes fed forage irrigated with sewage water or canal water. In particular, the transfer of sodium (Na), magnesium (Mg), potassium (K) and calcium (Ca) from soil to plant and in turn to animals was evaluated under sub-tropical environmental conditions. Samples of soil, forage and buffalo hair were collected and digested by wet method. Sodium and K concentrations were significantly higher in the soil but lower in the forages; however, Mg and Ca concentrations in both soil and forages were higher. The correlation between soil, forage and hair showed an imbalanced flow of Na, Mg and K and a balanced flow of Ca from soil to forage and then to animals. Based on the findings, the highest rates of transfer of minerals were found for sewage water treatment, whereas lowest rates were found for canal water treatment, except for Na. As the transfer of minerals depends on their bioavailability, the highest values may be due to the high rates of mineral uptake by plants. Thus, the high transfer rate of some elements by plants could become toxic in future causing detrimental effect to grazing livestock. 相似文献
123.
McDonald CB Buffa L Bar-Mag T Salah Z Bhat V Mikles DC Deegan BJ Seldeen KL Malhotra A Sudol M Aqeilan RI Nawaz Z Farooq A 《Journal of molecular biology》2012,422(1):58-74
The WW-containing oxidoreductase (WWOX) tumor suppressor participates in a diverse array of cellular activities by virtue of its ability to recognize WW-binding protein 1 (WBP1) and WW-binding protein 2 (WBP2) signaling adaptors among a wide variety of other ligands. Herein, using a multitude of biophysical techniques, we provide evidence that while the WW1 domain of WWOX binds to PPXY motifs within WBP1 and WBP2 in a physiologically relevant manner, the WW2 domain exhibits no affinity toward any of these PPXY motifs. Importantly, our data suggest that while R25/W44 residues located within the binding pocket of a triple-stranded β-fold of WW1 domain are critical for the recognition of PPXY ligands, they are replaced by the chemically distinct E66/Y85 duo at structurally equivalent positions within the WW2 domain, thereby accounting for its failure to bind PPXY ligands. Predictably, not only does the introduction of E66R/Y85W double substitution within the WW2 domain result in gain of function but the resulting engineered domain, hereinafter referred to as WW2_RW, also appears to be a much stronger binding partner of WBP1 and WBP2 than the wild-type WW1 domain. We also show that while the WW1 domain is structurally disordered and folds upon ligand binding, the WW2 domain not only adopts a fully structured conformation but also aids stabilization and ligand binding to WW1 domain. This salient observation implies that the WW2 domain likely serves as a chaperone to augment the physiological function of WW1 domain within WWOX. Collectively, our study lays the groundwork for understanding the molecular basis of a key protein-protein interaction pertinent to human health and disease. 相似文献
124.
Zafar Ali Masroor Ellahi Babar Jamil Ahmad Sajjad Ali Shah 《Indian journal of human genetics》2012,18(2):217-221
Families with at least 2 or more individuals having hereditary hearing loss were enrolled from different areas of Khyber Pakhtoonkhwa, mainly from district Peshawar. Detailed history was taken from each family to minimize the presence of other abnormalities and environmental causes for deafness. Families were questioned about skin pigmentation, hair pigmentation, and problems relating to balance, vision, night blindness, thyroid, kidneys, heart, and infectious diseases like meningitis, antibiotic usage, injury, and typhoid. The pedigree structures were based upon interviews with multiple family members, and pedigrees of the enrolled families were drawn using Cyrillic program (version 2.1). All families showed recessive mode of inheritance. I studied 8 families of these 10. For linkage analyses, studies for DFNB1 locus, 3 STR markers (D13S175, D13S292, and D13S787) were genotyped using polyacrylamide gel electrophoresis (PAGE) and haplotypes were constructed to determined, linkage with DFNB1 locus. From a total of 8 families, a single family-10 showed linkage to DFNB1 locus. 相似文献
125.
This study reports characteristics of different derivatives produced between CelA, a major endoglucanase of Clostridium thermocellum and carbohydrate binding domain of family 3a (CBM3a). In addition to the native form of the endoglucanase containing catalytic and dockerin domains (CelA-CD), its derivatives consisting of catalytic domain without dockerin domain (CelA-C), catalytic domain linked with the binding domain at N-, C- and both termini (CelA-BC, CelA-CB and CelA-BCB, respectively), two catalytic domains cloned in tandem (CelA-CC) and two catalytic domains intervened by a binding domain (CelA-CBC) were expressed in Escherichia coli at levels of 40, 43, 28, 30, 20, 20 and 10%, respectively of the total cell proteins. Specific activities of CelA-CD, CelA-C, CelA-BC, CelA-CB, CelA-CC, CelA-BCB and CelA-CBC against carboxymethyl cellulose (CMC) were 8.1, 7.0, 12.1, 8.5, 11.8, 10.2 and 23.5Umg(-1) enzyme while activities against pre-treated bagasse were 490, 250, 1400, 600, 810, 710 and 2270μmoles reducing sugars released per μmole of the enzyme, respectively, under the assay conditions used. Thus the activities of CelA-BC and CelA-CBC showed nearly 3- and 5-fold increase against pre-treated bagasse as compared to that of the native form of the enzyme, CelA-CD. Molecular modeling studies using MODELLER show that the binding residues of CBM3a and the active site residues of the catalytic domain are more favorably oriented for binding and hydrolysis of the polysaccharide in the case of CelA-BC as compared to those in CelA-CB, which corresponds with higher activity of the former. 相似文献
126.
Comparative genomic evidence for a close relationship between the dimorphic prosthecate bacteria Hyphomonas neptunium and Caulobacter crescentus
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Badger JH Hoover TR Brun YV Weiner RM Laub MT Alexandre G Mrázek J Ren Q Paulsen IT Nelson KE Khouri HM Radune D Sosa J Dodson RJ Sullivan SA Rosovitz MJ Madupu R Brinkac LM Durkin AS Daugherty SC Kothari SP Giglio MG Zhou L Haft DH Selengut JD Davidsen TM Yang Q Zafar N Ward NL 《Journal of bacteriology》2006,188(19):6841-6850
The dimorphic prosthecate bacteria (DPB) are alpha-proteobacteria that reproduce in an asymmetric manner rather than by binary fission and are of interest as simple models of development. Prior to this work, the only member of this group for which genome sequence was available was the model freshwater organism Caulobacter crescentus. Here we describe the genome sequence of Hyphomonas neptunium, a marine member of the DPB that differs from C. crescentus in that H. neptunium uses its stalk as a reproductive structure. Genome analysis indicates that this organism shares more genes with C. crescentus than it does with Silicibacter pomeroyi (a closer relative according to 16S rRNA phylogeny), that it relies upon a heterotrophic strategy utilizing a wide range of substrates, that its cell cycle is likely to be regulated in a similar manner to that of C. crescentus, and that the outer membrane complements of H. neptunium and C. crescentus are remarkably similar. H. neptunium swarmer cells are highly motile via a single polar flagellum. With the exception of cheY and cheR, genes required for chemotaxis were absent in the H. neptunium genome. Consistent with this observation, H. neptunium swarmer cells did not respond to any chemotactic stimuli that were tested, which suggests that H. neptunium motility is a random dispersal mechanism for swarmer cells rather than a stimulus-controlled navigation system for locating specific environments. In addition to providing insights into bacterial development, the H. neptunium genome will provide an important resource for the study of other interesting biological processes including chromosome segregation, polar growth, and cell aging. 相似文献
127.
Saima Riazuddin Saima Anwar Martin Fischer Shahid Y. Khan Ahmad U. Zafar Tayyab Husnain Penelope L. Friedman Thomas B. Friedman 《American journal of human genetics》2009,85(2):273-1241
BSND encodes barttin, an accessory subunit of renal and inner ear chloride channels. To date, all mutations of BSND have been shown to cause Bartter syndrome type IV, characterized by significant renal abnormalities and deafness. We identified a BSND mutation (p.I12T) in four kindreds segregating nonsyndromic deafness linked to a 4.04-cM interval on chromosome 1p32.3. The functional consequences of p.I12T differ from BSND mutations that cause renal failure and deafness in Bartter syndrome type IV. p.I12T leaves chloride channel function unaffected and only interferes with chaperone function of barttin in intracellular trafficking. This study provides functional data implicating a hypomorphic allele of BSND as a cause of apparent nonsyndromic deafness. We demonstrate that BSND mutations with different functional consequences are the basis for either syndromic or nonsyndromic deafness. 相似文献
128.
129.
The critically endangered and perennial alpine endemic angiosperms, namely, Aquilegia nivalis, Lagotis cashmeriana and Meconopsis latifolia inhabit such habitats in the Kashmir Himalaya that are characterised by short growing season and heavy snow cover for about
3–4 months during winter season. The seeds of these species under natural conditions experience a long period of pre-chilling
during winter prior to their germination in following spring season. Taking cue from such a requirement, present study investigated
the effect of chilling and exogenous application of growth hormones, NO3
− and NH4
+ on total percent germination of otherwise deep-dormant seeds of these species, under alternate light/dark and continuous
dark light regimes. Prolonged pre-chilling followed by treatment of seeds with different doses of GA3 had a pronounced stimulatory effect on the total germination percentage in all the three species. In fact, highest germination
percentage in A. nivalis was recorded only when pre-chilled seeds were treated with 1.5 mM GA3 under alternate light/dark conditions. Likewise, germination of pre-chilled seeds of L. cashmeriana with ruptured seed coats was improved when treated with various concentrations of GA3. Seed germination in M. latifolia was also favourably influenced by treatment of pre-chilled seeds with GA3 or nitrogen applied either as NO3
− or as NH4
+ under alternate light/dark conditions. Treatment of seeds with kinetin (6-furfuryl-aminopurine) had no significant influence
on germination percentage in any of the three species. Thus, prolonged chilling of seeds followed by their treatment with
GA3 under alternate light/dark conditions are the requirements necessary for seed germination in these species. 相似文献
130.
Anzar A. Khuroo Ewald Weber Akhtar H. Malik G. H. Dar Zafar A. Reshi 《Nordic Journal of Botany》2010,28(6):685-696
Biodiversity inventories unravel insightful taxonomic and biogeographic patterns that provide valuable inputs in guiding conservation practices and policymaking. Here we present an updated inventory of the native and alien woody flora of the Kashmir Himalaya, India, together with analyses of the patterns of taxonomic composition, geographic distribution, and invasion status of the alien species. The data was assembled from the floristic literature of the last two centuries, supplemented with herbarium records and validated by field surveys over the past decade. In total, the woody flora comprised of 520 species; out of these 322 species were native and 198 alien, yielding a proportion of 38% aliens. Amongst the natives, 16 species are on the IUCN red list 2009. While 37 genera included both native and alien species indicating a potential for hybrid formation, only 15 families were represented by alien species exclusively. Regarding the invasion status, presently 37 alien woody species are naturalized and 7 are invasive in the region. The results show that the Kashmir Himalaya harbours a diverse woody flora. It is concluded that a distinction between the native and the alien flora, as adopted in the present study, is crucial for a meaningful analysis of any biodiversity patterns. We predict that in the near future many alien woody species, presently naturalized in the region, can become serious plant invaders, and therefore need further research efforts and timely management. 相似文献