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711.
P. K. Swaminathan D. P. Vercauteren Kwang S. Kim E. Clementi 《Journal of biological physics》1986,14(2):49-56
We have performed detailed ab initio SCF calculations on the intermolecular interaction energies for one Na+ ion and one water molecule with two molecular fragments, one exemplifying a phospholipid (PL) head (PLHD) and the other, a phospholipid tail (PLTL). A 6-12-1 atom-atom pair potential for the interaction of a Na+ ion and water with a lysophosphatidyl-ethanolamine (LPEA) was derived from these results by a fitting procedure. This fitted potential was used to obtain isoenergy maps that provide energy profiles of the Na+ ion and the water around the phospholipids. The interaction of the Na+ ion with PL, as well as the interaction of water with the PL, can be visualized from these maps, which, as expected, show regions of hydrophilicity and hydrophobicity for the water and indicate a very strong binding site for the Na+ ion on the phosphate. It appears to be a stationary site that would limit the Na+ ion mobility. This binding site is located near the double-bonded oxygen atom of the phosphate group; its binding energy for Na+ is 67 kcal/mol. On the other hand the NH+ group of PLHD ahows strong electrostatic repulsion of Na+ while interacting with water with a binding energy of 13 kcal/mol. This potential energy well region for water is separated from another of similar depth near the phosphate by a barrier and both regions are expected to act as binding sites for water. 相似文献
712.
Chandrasekhar Gurramkonda Sulena Polez Natasa Skoko Ahmad Adnan Thomas Gäbel Dipti Chugh Sathyamangalam Swaminathan Navin Khanna Sergio Tisminetzky Ursula Rinas 《Microbial cell factories》2010,9(1):31
Background
The prevalence of diabetes is predicted to rise significantly in the coming decades. A recent analysis projects that by the year 2030 there will be ~366 million diabetics around the world, leading to an increased demand for inexpensive insulin to make this life-saving drug also affordable for resource poor countries. 相似文献713.
714.
715.
Purified beta subunit of human chorionic gonadotropin (hCG) was partially reduced with beta-mercaptoethanol, carboxymethylated, and digested with chymotrypsin. The peptides were isolated by high-voltage electrophoresis and paper chromatography. Five major disulfide-containing peptides were isolated, and their location in the parent molecule was established by amino acid composition and amino- and carboxy-terminal analyses. All of these peptides inhibited the binding of 125I-labeled hCG by anti-beta hCG serum. The inhibitory effect of these peptides was lost when their disulfide bonds were reduced and alkylated. Synthetic carboxy-terminal peptides were not inhibitory. Based on these data it is concluded that a major antigenic site of hCG resides in the region of residues 21-23 with a disulfide bond connecting cysteine-23 or -26 with the cysteines at positions 72 or 110. 相似文献
716.
Shuchismita Dutta Kyle Burkhardt Jasmine Young Ganesh J. Swaminathan Takanori Matsuura Kim Henrick Haruki Nakamura Helen M. Berman 《Molecular biotechnology》2009,42(1):1-13
The Protein Data Bank (PDB) is the repository for three-dimensional structures of biological macromolecules, determined by
experimental methods. The data in the archive is free and easily available via the Internet from any of the worldwide centers
managing this global archive. These data are used by scientists, researchers, bioinformatics specialists, educators, students,
and general audiences to understand biological phenomenon at a molecular level. Analysis of this structural data also inspires
and facilitates new discoveries in science. This chapter describes the tools and methods currently used for deposition, processing,
and release of data in the PDB. References to future enhancements are also included.
Shuchismita Dutta, Kyle Burkhardt, and Ganesh J. Swaminathan have contributed equally to this work. 相似文献
717.
Effect of ionic and nonionic detergents on the Taq polymerase 总被引:3,自引:0,他引:3
718.
Methylmercury (MeHg) is a well-recognized environmental contaminant with established health risk to human beings by fish and marine mammal consumption. Bacopa monniera (BM) is a perennial herb and is used as a nerve tonic in Ayurveda, a traditional medicine system in India. This study was aimed to evaluate the effect of B. monniera extract (BME) on MeHg-induced toxicity in rat cerebellum. Male Wistar rats were administered with MeHg orally at a dose of 5 mg/kg b.w. for 21 days. Experimental rats were given MeHg and also administered with BME (40 mg/kg, orally) 1 h prior to the administration of MeHg for 21 days. After treatment period, MeHg exposure significantly decreases the body weight and also caused the following behavioral changes. Decrease tail flick response, longer immobility time, significant decrease in motor activity, and spatial short-term memory. BME pretreatment reverted the behavioral changes to normal. MeHg exposure decreases the DNA and RNA content in cerebellum and also caused some pathological changes in cerebellum. Pretreatment with BME restored all the changes to near normal. These findings suggest that BME has a potent efficacy to alleviate MeHg-induced toxicity in rat cerebellum. 相似文献
719.
Tiina Myyryläinen Sheikh M Talha Sathyamangalam Swaminathan Raija Vainionpää Tero Soukka Navin Khanna Kim Pettersson 《Journal of nanobiotechnology》2010,8(1):27
A highly specific and novel dual-label time-resolved immunofluorometric assay was developed exploiting the unique emission
wavelengths of the intrinsically fluorescent terbium (Tb3+) and europium (Eu3+) tracers for the simultaneous detection of human immunodeficiency virus 1 (HIV-1) and hepatitis B virus (HBV) infections,
respectively. HIV-1 infection was detected using a double antigen sandwich format wherein anti-HIV-1 antibodies were captured
using an in vivo biotinylated version of a chimeric HIV-1 antigen and revealed using the same antigen labeled with Tb3+ chelate. Hepatitis B surface antigen (HBsAg), which served as the marker of HBV infection, was detected in a double antibody
sandwich using two monoclonal antibodies (mAbs), one chemically biotinylated to capture, and the other labeled with Eu3+ nanoparticles, to reveal. The performance of the assay was evaluated using a collection (n = 60) of in-house and commercially
available human sera panels. This evaluation showed the dual-label assay to possess high degrees of specificity and sensitivity,
comparable to those of commercially available, single analyte-specific kits for the detection of HBsAg antigen and anti-HIV
antibodies. This work demonstrates the feasibility of developing a potentially time- and resource-saving multiplex assay for
screening serum samples for multiple infections in a blood bank setting. 相似文献
720.
One-month-old plants of Porteresia coarctata were subjected to salt stress of 150 mM for 10 days. Changes induced in leaf proteins were studied by two-dimensional electrophoresis and quantitatively analyzed using image analysis. Thirty-five number of proteins were significantly affected by salt and seventeen were detected only in stressed plants. 相似文献