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1.
N A Rodionova G V Semisotnov V P Kutyshenko V N Uverski? I A Bolotina 《Molekuliarnaia biologiia》1989,23(3):683-692
It has been shown by 1H-NMR, circular dichroism, fluorescence and viscometry techniques that equilibrium unfolding of carbonic anhydrase B (a one-domain globular protein) in urea guanidine hydrochloride consists of two sequential stages. The first stage is connected with a decrease of intramolecular interactions, stabilizing the rigid tertiary structure and with the increase of mobility of aliphatic side chain groups. At the second stage the decrease of protein secondary structure and hydrophobic interactions take place as well as the increase of mobility of massive aromatic side chain groups. 相似文献
2.
Gorokhovatsky AY Rudenko NV Marchenkov VV Skosyrev VS Arzhanov MA Burkhardt N Zakharov MV Semisotnov GV Vinokurov LM Alakhov YB 《Analytical biochemistry》2003,313(1):68-75
Here we describe a homogeneous assay for biotin based on bioluminescence resonance energy transfer (BRET) between aequorin and enhanced green fluorescent protein (EGFP). The fusions of aequorin with streptavidin (SAV) and EGFP with biotin carboxyl carrier protein (BCCP) were purified after expression of the corresponding genes in Escherichia coli cells. Association of SAV-aequorin and BCCP-EGFP fusions was followed by BRET between aequorin (donor) and EGFP (acceptor), resulting in significantly increasing 510 nm and decreasing 470 nm bioluminescence intensity. It was shown that free biotin inhibited BRET due to its competition with BCCP-EGFP for binding to SAV-aequorin. These properties were exploited to demonstrate competitive homogeneous BRET assay for biotin. 相似文献
3.
Paulo FP Pimenta Alessandra S Orfano Ana C Bahia Ana PM Duarte Claudia M Ríos-Velásquez Fabrício F Melo Felipe AC Pessoa Giselle A Oliveira Keillen MM Campos Luis Martínez Villegas Nilton Barnabé Rodrigues Rafael Nacif-Pimenta Rejane C Sim?es Wuelton M Monteiro Rogerio Amino Yara M Traub-Cseko José BP Lima Maria GV Barbosa Marcus VG Lacerda Wanderli P Tadei Nágila FC Secundino 《Memórias do Instituto Oswaldo Cruz》2015,110(1):23-47
In the Americas, areas with a high risk of malaria transmission are mainly located in
the Amazon Forest, which extends across nine countries. One keystone step to
understanding the Plasmodium life cycle in Anopheles species from the Amazon Region
is to obtain experimentally infected mosquito vectors. Several attempts to colonise
Ano- pheles species have been conducted, but with only short-lived success or no
success at all. In this review, we review the literature on malaria transmission from
the perspective of its Amazon vectors. Currently, it is possible to develop
experimental Plasmodium vivax infection of the colonised and field-captured vectors
in laboratories located close to Amazonian endemic areas. We are also reviewing
studies related to the immune response to P. vivax infection of Anopheles aquasalis,
a coastal mosquito species. Finally, we discuss the importance of the modulation of
Plasmodium infection by the vector microbiota and also consider the anopheline
genomes. The establishment of experimental mosquito infections with Plasmodium
falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide
interesting models for studying malaria in the Amazonian scenario is important.
Understanding the molecular mechanisms involved in the development of the parasites
in New World vectors is crucial in order to better determine the interaction process
and vectorial competence. 相似文献
4.
Marchenkov VV Sokolovskiĭ IV Kotova NV Galzitskaya OV Bochkareva ES Girshovich AS Semisotnov GV 《Biofizika》2004,49(6):987-994
The main function of the chaperone GroEL is to prevent nonspecific association of nonnative protein chains and provide their correct folding. In the present work, the renaturation kinetics of three globular proteins (human alpha-lactalbumin, bovine carbonic anhydrase, and yeast phosphoglycerate kinase) in the presence of different molar excess of GroEL (up to 10-fold) was studied. It was shown that the formation of the native structure during the refolding of these proteins is retarded with an increase in GroEL molar excess due to the interaction of kinetic protein intermediates with the chaperone. Mg(2+)-ATP and Mg(2+)-ADP weaken this interaction and decrease the retarding effect of GroEL on the protein refolding kinetics. The theoretical modeling of protein folding in the presence of GroEL showed that the experimentally observed linear increase in the protein refolding half-time with increasing molar excess of GroEL must occur only when the protein adopts its native structure outside of GroEL (i.e. in the free state), while the refolding of the protein in the complex with GroEL is inhibited. The dissociation constants of GroEL complexed with the kinetic intermediates of the proteins studied were evaluated, and a simple mechanism of the functioning of GroEL as a molecular chaperone was proposed. 相似文献
5.
Structure based virtual screening of ligands to identify cysteinyl leukotriene receptor 1 antagonist
Srinivas Bandaru Vijaya Kumar Marri Priyadarshani Kasera Purnima Kovuri Amandeep Girdhar Deepti Raj Mittal Sabeen Ikram Ravi GV Anuraj Nayarisseri 《Bioinformation》2014,10(10):652-657
Montelukast and Zafirlukast are known leukotriene receptor antagonists prescribed in asthma treatment. However, these fall short
as mono therapy and are frequently used in combination with inhaled glucocorticosteroids with or without long acting beta 2
agonists. Therefore, it is of interest to apply ligand and structure based virtual screening strategies to identify compounds akin to
lead compounds Montelukast and Zafirlukast. Hence, compounds with structures having 95% similarity to these compounds were
retrieved from NCBI׳s PubChem database. Compounds similar to lead were grouped and docked at the antagonist binding site of
cysteinyl leukotriene receptor 1. This exercise identified compounds UNII 70RV86E50Q (Pub Cid 71587778) and Sure CN 9587085
(Pub Cid 19793614) with higher predicted binding compared to Montelukast and Zafirlukast. It is shown that the compound Sure
CN 9587085 showed appreciable ligand receptor interaction compared to UNII 70RV86E50Q. Thus, the compound Sure CN
9587085 is selected as a potent antagonist to cysteinyl leukotriene receptor 1 for further consideration in vitro and in vivo validation. 相似文献
6.
The folding of globular proteins occurs through intermediate states whose characterisation provides information about the mechanism of folding. A major class of intermediate states is the compact 'molten globule', whose characteristics have been studied intensively in those conditions in which it is stable (at acid pH, high temperatures and intermediate concentrations of strong denaturants). In studies involving bovine carbonic anhydrase, human alpha-lact-albumin, bovine beta-lactoglobulin, yeast phosphoglycerate kinase, beta-lactamase from Staphylococcus aureus and recombinant human interleukin 1 beta, we have demonstrated that a transient intermediate which accumulates during refolding is compact and has the properties of the 'molten globule' state. We show that it is formed within 0.1-0.2 s. These proteins belong to different structural types (beta, alpha + beta and alpha/beta), with and without disulphide bridges and they include proteins with quite different times of complete folding (from seconds to decades of minutes). We propose that the formation of the transient molten globule state occurs early on the pathway of folding of all globular proteins. 相似文献
7.
G V Semisotnov M Vas V V Chemeris N J Kashparova N V Kotova O I Razgulyaev M A Sinev 《European journal of biochemistry》1991,202(3):1083-1089
The time course of refolding of both pig muscle and yeast 3-phosphoglycerate kinase (molecular masses about 47 kDa), as well as their proteolytic C-terminal fragments (30 and 33 kDa, respectively) has been investigated. Very similar refolding kinetics (with half-time between 80-120 s, at 20 degrees C) were observed by fluorescence and ultraviolet absorbance spectroscopy, as well as by activity measurements, for the intact enzyme from both sources. This time course appears not to depend on the time the protein spends in the unfolded state, i.e. it is certainly not controlled by proline isomerization. Furthermore, after removal of a large N-terminal part (molecular mass of about 18 kDa for pig muscle enzyme or 13 kDa for yeast enzyme) of the molecule by proteolysis, refolding of the remaining C-terminal fragment of both proteins follows kinetics virtually indistinguishable from those of the intact protein molecule. 相似文献
8.
9.
Multiparametric kinetic study of bovine alpha-lactalbumin renaturation from the unfolded state has shown the existence of an intermediate which is formed within 10(-2) s with properties close to those of the molten globule. Apart from the fast kinetic phase which results in the intermediate, two slower phases were found with intrinsic times approximately 1 s and approximately 10 s. The slowest one is apparently due to proline isomerization. 相似文献
10.
Baryshnikova EN Melnik BS Finkelstein AV Semisotnov GV Bychkova VE 《Protein science : a publication of the Protein Society》2005,14(10):2658-2667
When considering protein folding with a transient intermediate, a difficulty arises as to determination of the rates of separate transitions. Here we overcome this problem, using the kinetic studies of the unfolding/refolding reactions of the three-state protein apomyoglobin as a model. Amplitudes of the protein refolding kinetic burst phase corresponding to the transition from the unfolded (U) to intermediate (I) state, that occurs prior to the native state (N) formation, allow us to estimate relative populations of the rapidly converting states at various final urea concentrations. On the basis of these proportions, a complicated experimental chevron plot has been deconvolved into the urea-dependent rates of the I<-->N and U<-->N transitions to give the dependence of free energies of the main transition state and of all three (N, I, and U) stable states on urea concentration. 相似文献