A5004429861- Enzyme Structure and Function
- Heat shock proteins research
- Protein Structure and Dynamics
- Connexins and lens biology
- Solid-state spectroscopy and crystallography
- Bacterial Genetics and Biotechnology
- Biochemical effects in animals
- DNA and Nucleic Acid Chemistry
- Advanced NMR Techniques and Applications
- RNA and protein synthesis mechanisms
- Phosphodiesterase function and regulation
- Molecular spectroscopy and chirality
- Crystal Structures and Properties
- Advanced biosensing and bioanalysis techniques
- Synthesis and Catalytic Reactions
- Pharmacological Effects of Natural Compounds
- Spectroscopy Techniques in Biomedical and Chemical Research
- Nonlinear Optical Materials Research
- DNA Repair Mechanisms
- RNA Interference and Gene Delivery
- Chemical Synthesis and Characterization
- S100 Proteins and Annexins
- Bone Metabolism and Diseases
- Yersinia bacterium, plague, ectoparasites research
- Exercise and Physiological Responses
University of Washington
1998-2016
Seattle University
2001-2010
University of Saskatchewan
1996
Texas A&M University
1996
University of Kerala
1988-1992
University of California, Los Angeles
1988-1989
Cataracts reduce vision in 50% of individuals over 70 years age and are a common form blindness worldwide. caused when damage to the major lens crystallin proteins causes their misfolding aggregation into insoluble amyloids. Using thermal stability assay, we identified class molecules that bind α-crystallins (cryAA cryAB) reversed vitro. The most promising compound improved transparency R49C cryAA R120G cryAB mouse models hereditary cataract. It also partially restored protein solubility...
The small heat shock protein (sHSP) αB-crystallin (αB) plays a key role in the cellular protection system against stress. For decades, high-resolution structural studies on heterogeneous sHSPs have been confounded by polydisperse nature of αB oligomers. We present an atomic-level model full-length as symmetric 24-subunit multimer based solid-state NMR, small-angle X-ray scattering (SAXS), and EM data. builds our recently reported structure homodimeric α-crystallin domain (ACD) C-terminal IXI...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNMR studies of triple-strand formation from the homopurine-homopyrimidine deoxyribonucleotides d(GA)4 and d(TC)4Ponni Rajagopal Juli FeigonCite this: Biochemistry 1989, 28, 19, 7859–7870Publication Date (Print):September 1989Publication History Published online1 May 2002Published inissue 19 September 1989https://pubs.acs.org/doi/10.1021/bi00445a048https://doi.org/10.1021/bi00445a048research-articleACS PublicationsRequest reuse permissionsArticle...
Small heat shock proteins (sHSPs) are essential ‘holdase’ chaperones that form large assemblies and respond dynamically to pH temperature stresses protect client from aggregation. While the alpha-crystallin domain (ACD) dimer of sHSPs is universal building block, how ACD transmits structural changes in response stress promote holdase activity unknown. We found interface HSPB5 destabilized over physiological pHs a conserved histidine (His-104) controls stability oligomer structure acidosis....
Abstract The solution structure of the phosphocarrier protein, HPr, from Bacillus subtilis has been determined by analysis two‐dimensional (2D) NMR spectra acquired for unphosphorylated form protein. Inverse‐detected 2D ( 1 H‐ 15 N) heteronuclear multiple quantum correlation nuclear Overhauser effect (HMQC NOESY) and homonuclear Hartmann‐Hahn (HOHAHA) utilizing N assignments (reported here) as well previously published H were used to identify cross‐peaks that are not resolved in spectra....
BARD1 is the constitutive nuclear partner to breast and ovarian cancer-specific tumor suppressor BRCA1. Together, they form a heterodimeric complex responsible for maintaining genomic stability through functions involving DNA damage signaling repair, transcriptional regulation, cell cycle control. We report 2.0A structure of ankyrin repeat domain. The includes four repeats with non-canonical C-terminal capping well ordered extended loop preceding first repeat. Conserved surface features show...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructural Consequences of Histidine Phosphorylation: NMR Characterization the Phosphohistidine Form Histidine-Containing Protein from Bacillus subtilis and Escherichia coliPonni Rajagopal, E. Bruce Waygood, Rachel KlevitCite this: Biochemistry 1994, 33, 51, 15271–15282Publication Date (Print):December 1, 1994Publication History Published online1 May 2002Published inissue 1 December...
Phosphodiesterase 5 (PDE5) controls intracellular levels of cGMP through its regulation hydrolysis. Hydrolytic activity the C-terminal catalytic domain is increased by binding to N-terminal GAF A domain. We present NMR solution structure cGMP-bound PDE5A The orientation in buried pocket was defined 37 intermolecular nuclear Overhauser effects. Comparison with domains from PDE2A and adenylyl cyclase cyaB2 reveals a conserved overall fold six-stranded beta-sheet four alpha-helices that form...
Abstract Chemical shift mapping is becoming a popular method for studying protein‐protein interactions in solution. The technique used to identify putative sites of interaction on protein surface by detecting chemical perturbations simple ( 1 H, 15 N )‐HSQC NMR spectra uniformly labeled as function added (unlabeled) target protein. high concentrations required these experiments raise questions concerning the possibility non‐specific being detected, thereby compromising information obtained....
Abstract The serine‐phosphorylated form of histidine‐containing protein (HPr), a component the phosphoenol‐pyruvate:sugar phosphotransferase system from Bacillus subtilis , has been characterized by NMR spectroscopy and solvent denaturation studies. results indicate that phosphorylation Ser 46, N‐cap α ‐helix‐B, does not cause conformational change but rather stabilizes helix. Amide proton exchange rates in helix‐B are decreased to thermal denaturation, with ΔΔ G 0.7‐0.8 kcal mol −1 . A...
Abstract The histidine‐containing protein (HPr) of bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) serves a central role in series phosphotransfer reactions used for the translocation sugars across cell membranes. These studies report high‐definition solution structures both unphosphorylated and histidine phosphorylated (P‐His) forms HPr from Bacillus subtilis. Consistent with previous NMR studies, local conformational adjustments occur upon phosphorylation His 15, which...
This paper describes the effect of N-capping substitutions on structure and stability histidine-containing protein (HPr). We have used NMR spectroscopy conformational studies to quantify changes in local global free energy due mutagenesis at Ser46, N-cap for helix B HPr. Previous suggested that Escherichia coli HPr is dynamic as judged by rate exchange amide protons with solvent. Ser46 was chosen because it site regulatory phosphorylation HPrs from Gram-positive bacteria, mutation this...
The IR and polarized Raman spectra of (NH4)2Mg(SO4)2 · 6 H2O have been recorded analysed. vibrations NH ion, SO the complex [Mg(OH2)6]2+, three different water molecules are identified. isomorphous nature ammonium salt with corresponding potassium is established. linear distortion ion found to be greater than its angular distortion, while has suffered more distortion. possibility free rotation ruled out. L'infrarouge et le spectre polarisé de ont été notés analysés. Les l'ion SO, complexe...
The simplified SH3 domain sequence, FP1, obtained in phage display selection experiments has an amino acid composition that is 95% Ile, Lys, Glu, Ala, Gly. Here we use NMR to investigate the tertiary structure of FP1. We find overall topology FP1 resembles src domain, hydrogen-deuterium exchange and chemical shift perturbation profiles are similar those naturally occurring domains, (15)N relaxation rates range small proteins. Guided by structure, further simplify sequence compare effects on...
Abstract Mutagenesis studies have revealed that the minimal DNA‐binding domain of yeast transcription factor ADR1 consists two Cys 2 ‐His zinc fingers plus an additional 20 residues proximal and N‐terminal to fingers. We assigned NMR 1 'H, 15 N, 13 C chemical shifts for entire both free bound specific DNA. H shift values suggest little structural difference between in this construct single‐finger constructs, α index analysis indicates change finger structure upon DNA binding. perturbations...