A5025613824- Protein Structure and Dynamics
- Enzyme Structure and Function
- Research on Leishmaniasis Studies
- Lipid metabolism and biosynthesis
- Glycosylation and Glycoproteins Research
- Enzyme Production and Characterization
- Biochemical and Molecular Research
- Chemical Synthesis and Analysis
- Carbohydrate Chemistry and Synthesis
- Biotin and Related Studies
- Ubiquitin and proteasome pathways
- Peptidase Inhibition and Analysis
- Trypanosoma species research and implications
- Cancer, Lipids, and Metabolism
- RNA and protein synthesis mechanisms
- Biochemical Acid Research Studies
- Monoclonal and Polyclonal Antibodies Research
- Photosynthetic Processes and Mechanisms
- Hemoglobin structure and function
- Antimicrobial Peptides and Activities
- Microbial Natural Products and Biosynthesis
- Metabolism and Genetic Disorders
- Malaria Research and Control
- Parkinson's Disease Mechanisms and Treatments
- Cellular transport and secretion
National Institute of Immunology
2015-2024
Iowa State University
2006
Institute of Medical Sciences
1998-2004
Banaras Hindu University
1998-2004
Saha Institute of Nuclear Physics
2004
University of Iowa
2002-2003
Universidad de Granada
2002
Abstract Dietary polyunsaturated fatty acids (PUFA) are increasingly recognized for their health benefits, whereas a high production of endogenous – process called de novo lipogenesis (DNL) - is closely linked to metabolic diseases. Determinants PUFA incorporation into complex lipids insufficiently understood and may influence the onset progression Here we show that acid synthase (FASN), key enzyme DNL, critically determines use dietary in mice humans. Moreover, combination FASN inhibition...
E. coli expression system is the method of choice to obtain high yields a pure protein. However, there always chance that an overexpressed protein shares structural or sequence homology with substrate enzyme. In such cases, expressed may be partially fully converted into product. A notable example acyl carrier proteins (ACP) in coli. Since most type II ACPs fatty acid synthesis pathway (FAS) have conserved helix II, are recognized as by Holo-acyl synthase (AcpS). Thus, express loaded This...
To explore electrostatic interactions in ubiquitin, pKa values have been determined by NMR for all 12 carboxyl groups wild-type ubiquitin and variants where single lysines replaced neutral residues. Aspartate range from 3.1 to 3.8 are generally less than model compound values. Most aspartate within 0.2 pH unit of those predicted with a simple Tanford−Kirkwood model. Glutamate 4.5, close differing 0.1−0.8 calculated determine the role positive charges modulating values, we mutated at...
Latex of the medicinal plant Ervatamia coronaria was found to contain at least three cysteine proteases with high proteolytic activity, called ervatamins. One these proteases, named ervatamin B, has been purified homogeneity using ion-exchange chromatography and crystallization. The molecular mass enzyme estimated be 26 000 Da by SDS−PAGE gel filtration. extinction coefficient (ε1%280 nm) 20.5 7 tryptophan 10 tyrosine residues per molecule. hydrolyzed denatured natural substrates such as...
α-Synuclein (αS) is an intrinsically disordered protein whose aggregation and deposition in Lewy bodies involved the progression of Parkinson's disease (PD) other related disorders. The process αS also triggered by mutations like A53T E46K SNCA gene disruption metal-ion homeostasis. Currently, there no obviating therapy available market that could effectively prevent disease. In this backdrop, exists emerging need to consider naturally occurring polyphenols flavonoids as potential...
A highly stable cysteine protease was purified to homogeneity from the latex of Ervatamia coronaria by a simple purification procedure involving ammonium sulfate precipitation and ion-exchange chromatography. The molecular mass estimated be approximately 25,000 Da SDS-PAGE gel filtration. extinction coefficient (ε280 nm1%) enzyme 24.6. hydrolyzed denatured natural substrates like casein, hemoglobin, azoalbumin, azocasein with high specific activity but showed low towards synthetic...
Acyl carrier protein (ACP) plays a central role in fatty acid biosynthesis. However, the molecular machinery that mediates its function is not yet fully understood. Therefore, structural studies were carried out on acyl-ACP intermediates of Plasmodium falciparum using NMR as spectroscopic probe. Chemical shift perturbation put forth new picture interaction ACP molecule with acyl chain, namely, hydrophobic core can protect up to 12 carbon units, and additional carbons protrude from top...
Pyrococcus furiosus rubredoxin (PfRd), a small, monomeric, 53 residues-long, iron-containing, electron-transfer protein of known structure is sometimes referred to as being the most structurally-stable man. Here, using combination mutational and spectroscopic (CD, fluorescence, NMR) studies differently made holo- apo-forms PfRd, we demonstrate that it not presence iron, or even folding PfRd chain into compact well-folded causes holo-PfRd display its extraordinary thermal stability, but...
Ervatamin C is an unusually stable cysteine protease from the medicinal plant Ervatamia coronaria belonging to papain family. Though it cleaves denatured natural proteins with high specific activity, its activity toward some small synthetic substrates found be insignificant. The three-dimensional structure and amino acid sequence of protein have been determined X-ray diffraction data at 1.9 Å (R = 17.7% Rfree 19.0%). overall ervatamin similar those other homologous proteases family, folding...
Plants have a history of being employed in managing breast cancer. However, no scientific evidence supports the idea that these plants can effectively reduce level HER2 expression. In this study, extracts from 10 medicinal were evaluated for their anticancer properties against HER2-positive cancer cells through various methods, including SRB assay, comet annexin V-FITC dual staining, and immunoblotting. All exerted antiproliferative activity cells. Furthermore,
Structure, stability and dynamics properties of horse cytochrome c (cyt c) its genetically engineered M80G mutant have been investigated. The nature the Met80 axial ligation to heme iron is believed be major determinant oxidation-reduction reactions inside outside cell a particular cytochrome. This has played an important role in studies protein structure, folding/unfolding. To understand this better, cyt mutated Gly that unable bind iron. We examined effect mutation on structure WT (wild...
Interaction interfaces comprise a finite number of sequence/structural motifs, which are often repeated in nature. Here we show how helical motif present the acyl carrier protein (ACP), involved multiprotein interactions, displays binding interface similar to that "ubiquitin interacting (UIM)". Analysis crystal structures ACP–enzyme complexes gave first hint helix II ACP ("universal recognition helix") utilizes UIM-like noncovalent interactions associate with type fatty acid biosynthesis...
The structural and functional aspects of ervatamin B were studied in solution. Ervatamin belongs to the <TEX>$\alpha+\beta$</TEX> class proteins. intrinsic fluorescence emission maximum enzyme was at 350 nm under neutral conditions, 355 denaturing conditions. Between pH 1.0-2.5 exists a partially unfolded state with minimum or no tertiary structure, proteolytic activity. At still lower pH, regains substantial secondary which is predominantly <TEX>$\beta$</TEX>-sheet conformation shows strong...
Src homology domain containing leukocyte protein of 65 kDa (SLP65), the growth factor receptor binding 2 (Grb2), and guanine nucleotide exchange for Rho family GTPases (Vav), self associate in unstimulated B cells as components preformed cell transducer module, an SH3-dependent manner. The complex enables to promptly respond BCR aggregation, resulting signal amplification. It also facilitates Vav translocation membrane rafts, activation. Here we uncover molecular mechanism by which may be...
The structural aspects of ervatamin B have been studied in different types alcohol. This alcohol did not affect the structure or activity under neutral conditions. At a low pH (3.0), kinds effects. Interestingly, at certain concentration non-fluorinated, aliphatic, monohydric alcohol, conformational switch from predominantly <TEX>$\alpha$</TEX>-helical to <TEX>$\beta$</TEX>-sheeted state is observed with complete loss tertiary and proteolytic activity. contrary observation that induces...
Ubiquitin interacts with numerous domains and motifs in its lifetime that vary structure but bind the same hydrophobic patch. To identify structural features of ubiquitin make it an exceptional protein–protein interaction partner, we have studied signal transducing adaptor molecule-1 interacting motif (UIM) using nuclear magnetic resonance. Our studies bring to light role inherent backbone flexibility interactions a large array binding partners, revealed from changes Cα chemical shifts,...