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81.
Sri Andrijany Vinsencia Indrayanto Gunawan Adi Soehono Loekito 《Plant Cell, Tissue and Organ Culture》1998,55(2):103-108
The simultaneous effect of calcium, cobalt, copper and magnesium ions and their interactions on growth and sapogenin steroids
accumulation in callus cultures of Agave amaniensis was studied by using a central composite second-order rotatable design.
The absence of calcium ions in media increased the sapogenin steroid content, while relatively high concentration of magnesium,
cobalt and copper ions simultaneously inhibited the sapogenin steroid formation.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
82.
J Sri Widada J Asselin S Colote C Ferraz G Travé M Afshar J Haiech J P Liautard 《Biochimie》1990,72(1):19-24
A cDNA clone producing a protein that binds calmodulin has been isolated from a mouse macrophage library. The cDNA was sequenced and identified as coding for fodrin. By deleting part of the sequence, the calmodulin binding domain was located. The site is situated on repeat 11 of fodrin probably on its extra arm. This part of the sequence exhibits great similarity to other calmodulin binding proteins. Analysis of the sequence and spatial structure of calmodulin revealed a domain which is quite complementary to the sequence identified on fodrin. These results provide a new insight into the structure of fodrin and consequently into the structure of proteins of the spectrin family. A model for the general folding of these molecules is proposed, involving a simple three-layer folding. The structure was further corroborated by analysis of charge distribution in the vicinity of the calmodulin binding site. The folding we propose is in good agreement with digestion experiments and explains observations in diseases resulting from mutations of human spectrin. 相似文献
83.
Ashim C Roy Michael Yeang Suan Mian Tan Sri R Kottegoda Shan S Ratnam 《Prostaglandins & other lipid mediators》1985,30(2):255-261
Two isoenzymes of oxytocinase (EC 3.4.11.3) activity were fractionated from human amniotic fluid samples between the 14th and 22nd weeks of gestation by Ultrogel acrylamide-agarose gel filtration and partially characterized. The isoenzymes were competitively inhibited by PGE1, PGE2 and PGF2α more at pH 6.2 than at pH 6.8, whereas cyclic GMP (cGMP) and its 8-bromo derivative had no effect at either pH. The implications of these findings are discussed and it is suggested that since the activity of amniotic fluid oxytocinases is very low or minimal at or near term, inhibition of these by prostaglandins may not have physiological significance in the initiation of human parturition. 相似文献
84.
Summary A 36-month-old boy presented with short stature, short neck, shield-shaped chest, and mental retardation. Chromosome analysis showed trisomy for the short arm and the proximal portion of the long arm of chromosome 13 [47,XY,+der(13),t(13;22)(q12;q13)mat]. The patient's mother has a balanced translocation between the long arms of chromosomes 13 and 22 [46,XX,t(13;22)(q12;q13)]. The patient's neutrophils showed an elevated number of nuclear projections and his fetal hemoglobin level was undetectable. 相似文献
85.
Ashbury Alison M. Meric de Bellefon Jade Kunz Julia A. Abdullah Misdi Marzec Anna M. Fryns Caroline Utami Atmoko Sri Suci van Schaik Carel P. van Noordwijk Maria A. 《International journal of primatology》2022,43(2):189-215
International Journal of Primatology - As climate change continues to fundamentally alter resource landscapes, the ability to flexibly respond to spatio-temporal changes in the distribution of... 相似文献
86.
Alan K. Hunter Kamiyar Rezvani Matthew T. Aspelund Guoling Xi Dhanesh Gadre Thomas Linke Kang Cai Sri Hari Raju Mulagapati Tomasz Witkos 《Biotechnology progress》2022,38(2):e3235
We have systematically investigated six compendial nonionic detergents as potential replacements for Triton ×-100 in bioprocessing applications. Use of compendial raw materials in cGMP bioprocessing is advantageous for a variety of reasons including material specifications developed to meet stringent pharmaceutical product quality requirements, regulatory familiarity and comfort, and availability from vendors experienced supplying the biopharmaceutical industry. We first examine material properties of the detergents themselves including melting point and viscosity. Process performance and product contact in real-world bioprocess applications are then investigated. Lastly, we test the detergents in virus inactivation (VI) experiments with recombinant proteins and adeno-associated virus. Two of the detergents tested, PEG 9 Lauryl Ether and PEG 6 Caprylic/Capric Glycerides, showed favorable properties that make them attractive for use as potential Triton X-100 replacements. Process performance testing indicated negligible impact of the detergents on product yield, purity, and activity compared to a control with no detergent. Importantly, both PEG 9 Lauryl Ether and PEG 6 Caprylic/Capric Glycerides demonstrated very fast VI kinetics with complete inactivation of XMuLV observed in less than 1 min at a target 1% detergent concentration. Potential advantages and disadvantages of both candidate detergents for use in cGMP bioprocessing are summarized and discussed. 相似文献
87.
Bai F Minkin P Fraga CH O'Shaughnessy MA Gururangan S Stewart CF 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,853(1-2):97-104
A sensitive method for the determination of Cloretazine (VNP40101M) and its metabolite (VNP4090CE) with an internal standard (ISTD) in human plasma was developed using high-performance liquid chromatographic separation with tandem mass spectrometric detection. Acidified plasma samples (500 microL) were prepared using solid phase extraction (SPE) columns, and 25 microL of the reconstituted sample was injected onto an Ascentis C18 HPLC column (3 microm, 5 cmx2.1 mm) with an isocratic mobile phase. Analytes were detected with an API-3000 LC-MS/MS System at unit (Q1) and low (Q3) resolution in negative multiple reaction monitoring mode: m/z 249.0 (precursor ion) to m/z 114.9 (product ion) for both Cloretazine (at 3.64 min) and VNP4090CE (at 2.91 min), and m/z 253.0 (precursor ion) to m/z 116.9 (product ion) for the ISTD. The mean recovery for Cloretazine (VNP40101M) and its metabolite (VNP4090CE) was greater than 87% with a lower limit of quantification of 1.0 ng/mL for Cloretazine (S/N=9.7, CV相似文献
88.
Sathyan Sri Lavvanya Priya Ponnuswamy Renuka Devi Palanisami Eganathan Nishith Saurav Topno 《Bioinformation》2012,8(16):742-748
Bestrophin, an integral membrane protein existing in basolateral region of the retina is a propitious target for drug discovery.
Mutations in the Bestrophin protein cause Best Vitelliform Macular Dystrophy (BVMD) leading to retinal damages and loss of
visual acuity. Owing to the lack of three dimensional structure and related structural homologs in the protein data bank, we
modeled the bestrophin protein using Robetta ab initio method. Further, no treatment is available for the disease. In this situation,
anthocyanins from natural sources are reported to combat retinal damages. Hence, we identified anthocyanins from Syzygium
cumini fruit skin using Electrospray Ionization tandem mass spectrometry. These compounds were docked into the predicted
bestrophin model to study the interactions within the active site. The results may provide a valuable insight into the structure of
bestrophin and efficacy of anthocyanins in molecular docking studies.
Abbreviations
PTP - Putative transmembrane proteins, VMD - Vitelliform macular dystrophy, BVMD - Best''s vitelliform macular dystrophy, RPE - Retinal pigment epithelium, ESI-MS/MS - Electrospray Ionization Tandem Mass Spectrometry, UNIPROT - Universal Protein Resource, PSIPRED - Protein secondary structure prediction, TMH - Transmembrane Helices, SCFS - Syzygium cumini fruit skin DP - Declustering Potential IFD - Induced Fit Docking. 相似文献89.
Perez-Jimenez R Garcia-Manyes S Ainavarapu SR Fernandez JM 《The Journal of biological chemistry》2006,281(52):40010-40014
We used single molecule force spectroscopy to characterize the mechanical stability of the enhanced yellow fluorescent protein (EYFP) (a mutant form of the green fluorescent protein (GFP)) and two of its circularly permutated variants. In all three constructs, we found two main unfolding peaks; the first corresponds to a transition state placed close to the termini and the second to a transition state placed halfway through the molecule. We attribute the second transition state to the shear rupture of the beta1- and beta6-strands, which we verified by introducing a point mutation in this region. Although both unfolding peaks were observed in all three EYFP variants, their relative frequency of occurrence varied. Our results demonstrated that the mechanical unfolding pathways in EYFP could be deciphered through the use of circular permutation. 相似文献
90.