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91.
Fatemeh Rahimi Gharemirshamlu Maliha Afsar Taseem A. Mokhdomi Asif Amin Shoiab Bukhari Anbarasu Krishnan Chundi Vinay Kumar Kourosh Bamdad Trupti N. Patel Raies A. Qadri Naveed Anjum Chikan Nadeem Shabir 《Journal of cellular biochemistry》2019,120(5):7701-7710
Follicle-stimulating hormone-follicle-stimulating hormone receptor (FSH-FSHR) interaction is one of the most thoroughly studied signaling pathways primarily because of being implicated in sexual reproduction in mammals by way of maintaining gonadal function and sexual fertility. Despite material advances in understanding the role of point mutations, their mechanistic basis in FSH-FSHR signaling is still confined to mystically altered behavior of sTYS335 (sulfated tyrosine) yet lacking a substantial theory. To understand the structural basis of receptor modulation, we choose two behaviorally contradicting mutations, namely S128Y (activating) and D224Y (inactivating), found in FSH receptor responsible for ovarian hyperstimulation syndrome and ovarian dysgenesis, respectively. Using short-term molecular dynamics simulations, the atomic scale investigations reveal that the binding pattern of sTYS with FSH and movement of the thumb region of FSHR show distinct contrasting patterns in the two mutants, which supposedly could be a critical factor for differential FSHR behavior in activating and inactivating mutations. 相似文献
92.
Iqra Ishaaq Muhammad Umer Farooq Syeda Anjum Tahira Rizwana Maqbool Celaleddin Barutçular Muhammad Yasir Saira Bano Zaid Ulhassan Ghassan Zahid Muhammad Ahsan Asghar Sajad Hussain Kocsy Gabor Ulkar Ibrahimova Jianqing Zhu Anshu Rastogi 《Phyton》2022,91(12):2733-2758
Drought is the major detrimental environmental factor for wheat (Triticum aestivum L.) production. The exploration of genetic patterns underlying drought tolerance is of great significance. Here we report the gene actions controlling the phenological traits using the line × tester model studying 27 crosses and 12 parents under normal irrigation and drought conditions. The results interpreted via multiple analysis (mean performance, correlations, principal component, genetic analysis, heterotic and heterobeltiotic potential) disclosed highly significant differences among germplasm. The phenological waxiness traits (glume, boom, and sheath) were strongly interlinked. Flag leaf area exhibits a positive association with peduncle and spike length under drought. The growing degree days (heat-units) greatly influence spikelets and grains per spike, however, the grain yield/plant was significantly reduced (17.44 g to 13.25 g) under drought. The principal components based on eigenvalue indicated significant PCs (first-seven) accounted for 79.9% and 73.9% of total variability under normal irrigation and drought, respectively. The investigated yield traits showed complex genetic behaviour. The genetic advance confronted a moderate to high heritability for spikelets/spike and grain yield/plant. The traits conditioned by dominant genetic effects in normal irrigation were inversely controlled by additive genetic effects under drought and vice versa. The magnitude of dominance effects for phenological and yield traits, i.e., leaf twist, auricle hairiness, grain yield/plant, spikelets, and grains/spike suggests that selection by the pedigree method is appropriate for improving these traits under normal irrigation conditions and could serve as an indirect selection index for improving yield-oriented traits in wheat populations for drought tolerance. However, the phenotypic selection could be more than effective for traits conditioned by additive genetic effects under drought. We suggest five significant cross combinations based on heterotic and heterobeltiotic potential of wheat genotypes for improved yield and enhanced biological production of wheat in advanced generations under drought. 相似文献
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95.
Faridoon Hussein WM Ul Islam N Guddat LW Schenk G McGeary RP 《Bioorganic & medicinal chemistry letters》2012,22(7):2555-2559
Purple acid phosphatases (PAPs) are binuclear metallohydrolases that have a multitude of biological functions and are found in fungi, bacteria, plants and animals. In mammals, PAP activity is linked with bone resorption and over-expression can lead to bone disorders such as osteoporosis. PAP is therefore an attractive target for the development of drugs to treat this disease. A series of penicillin conjugates, in which 6-aminopenicillanic acid was acylated with aromatic acid chlorides, has been prepared and assayed against pig PAP. The binding mode of most of these conjugates is purely competitive, and some members of this class have potencies comparable to the best PAP inhibitors yet reported. The structurally related penicillin G was shown to be neither an inhibitor nor a substrate for pig PAP. Molecular modelling has been used to examine the binding modes of these compounds in the active site of the enzyme and to rationalise their activities. 相似文献
96.
Faridoon Hussein WM Vella P Islam NU Ollis DL Schenk G McGeary RP 《Bioorganic & medicinal chemistry letters》2012,22(1):380-386
The production of β-lactamases is an effective strategy by which pathogenic bacteria can develop resistance against β-lactam antibiotics. While inhibitors of serine-β-lactamases are widely used in combination therapy with β-lactam antibiotics, there are no clinically available inhibitors of metallo-β-lactamases (MBLs), and so there is a need for the development of such inhibitors. This work describes the optimisation of a lead inhibitor previously identified by fragment screening of a compound library. We also report that thiosemicarbazide intermediates in the syntheses of these compounds are also moderately potent inhibitors of the IMP-1 MBL from Pseudomonas aeruginosa. The interactions of these inhibitors with the active site of IMP-1 were examined using in silico methods. 相似文献
97.
Mustafa G Khan IU Ashraf M Afzal I Shahzad SA Shafiq M 《Bioorganic & medicinal chemistry》2012,20(8):2535-2539
The present study describes a convenient method for the synthesis of new lipoxygenase inhibitors, 4-(toluene-4-sulfonylamino)-benzoic acids from p-amino benzoic acid. Reaction of p-amino benzoic acid with p-toluenesulfonyl chloride provided thirteen N- and O-alkylation products 4a-4m in moderate to good yields. Lipoxygenase inhibition of newly formed sulfonamide derivatives was investigated and some of these compounds 4m, 4g, 4e, 4f and 4j showed good lipoxygenase inhibitory activities with IC(50) values ranged between 15.8 ± 0.57 and 91.7 ± 0.61 μmol whilst all other compounds exhibited mild anti-lipoxygenase activities with IC(50) values ranged between 139.2 ± 0.75 and 232.1 ± 0.78 μmol. N-alkylated products were more active against the enzyme than O-alkylated or both N- and O-alkylated ones. All synthesized sulfonamides were recrystallized in chloroform to give these title compounds which were characterized using FTIR, (1)H NMR, (13)C NMR, elemental analysis and single crystal X-ray diffraction techniques. 相似文献
98.
Cretoiu MS Kielak AM Abu Al-Soud W Sørensen SJ van Elsas JD 《Applied microbiology and biotechnology》2012,94(5):1347-1358
The main objective of this study was to assess the abundance and diversity of chitin-degrading microbial communities in ten terrestrial and aquatic habitats in order to provide guidance to the subsequent exploration of such environments for novel chitinolytic enzymes. A combined protocol which encompassed (1) classical overall enzymatic assays, (2) chiA gene abundance measurement by qPCR, (3) chiA gene pyrosequencing, and (4) chiA gene-based PCR-DGGE was used. The chiA gene pyrosequencing is unprecedented, as it is the first massive parallel sequencing of this gene. The data obtained showed the existence across habitats of core bacterial communities responsible for chitin assimilation irrespective of ecosystem origin. Conversely, there were habitat-specific differences. In addition, a suite of sequences were obtained that are as yet unregistered in the chitinase database. In terms of chiA gene abundance and diversity, typical low-abundance/diversity versus high-abundance/diversity habitats was distinguished. From the combined data, we selected chitin-amended agricultural soil, the rhizosphere of the Arctic plant Oxyria digyna and the freshwater sponge Ephydatia fluviatilis as the most promising habitats for subsequent bioexploration. Thus, the screening strategy used is proposed as a guide for further metagenomics-based exploration of the selected habitats. 相似文献
99.
Gamil A. Amin Narmen A. Youssef Saleh Bazaid Waleed D. Saleh 《World journal of microbiology & biotechnology》2010,26(12):2263-2268
Insecticidal activity of the red pigment produced by a strain of the fungus Beauveria
bassiana that was locally isolated from infected whitefly, Bemisia
tabaci (Genn.) was assessed. The pigment is produced extracellularly and is a water-soluble. This makes it easy and simple to be
recovered from fermentation broth and used in pathogenicity experiments. When applied alone to Bm. tabaci nymphs, mortality percentages of 18% was recorded. For nymphs treated with Bv. bassiana spore suspension, mortality was 60%. The best results were obtained when red pigment was combined with fungal spores with
the mortality percentage being increased to up to 92%. The highest insecticidal activity against adults emerging later on
from the surviving larvae of Bm. tabaci was recorded also with treatment combining pigment and fungal spores with the longest days to pupation. 相似文献
100.
Bo Tang David L Cullins Jing Zhou Janice A Zawaski Hyelee Park David D Brand Karen A Hasty M Waleed Gaber John M Stuart Andrew H Kang Linda K Myers 《Arthritis research & therapy》2010,12(4):R136