A5036508784- Bacterial Genetics and Biotechnology
- RNA and protein synthesis mechanisms
- Tuberculosis Research and Epidemiology
- Mycobacterium research and diagnosis
- Bacteriophages and microbial interactions
- Enzyme Structure and Function
- Genomics and Phylogenetic Studies
- Biochemical and Molecular Research
- Protein Structure and Dynamics
- Microbial Metabolic Engineering and Bioproduction
- Antibiotic Resistance in Bacteria
- Advanced Electron Microscopy Techniques and Applications
- Escherichia coli research studies
- Force Microscopy Techniques and Applications
- Microbial Metabolism and Applications
- Ion channel regulation and function
- Photosynthetic Processes and Mechanisms
- Enzyme Catalysis and Immobilization
- Lipid Membrane Structure and Behavior
- RNA modifications and cancer
- Advanced Proteomics Techniques and Applications
- Monoclonal and Polyclonal Antibodies Research
- Chemical Synthesis and Analysis
- ATP Synthase and ATPases Research
- Nanofabrication and Lithography Techniques
University of California, Los Angeles
2013-2024
Genomics (United Kingdom)
2022
Protein Express (United States)
2015-2020
Uniformed Services University of the Health Sciences
2016
University of Dundee
2016
Howard Hughes Medical Institute
2013-2015
Columbia University
2009-2010
McGill University
2000-2003
Designed protein cages and related materials provide unique opportunities for applications in biotechnology medicine, but their creation remains challenging. Here, we apply computational approaches to design a suite of tetrahedrally symmetric, self-assembling cages. For the generation docked conformations, emphasize fragment-based approach, while sequence de novo interface, comparison knowledge-based machine learning protocols highlights power increased experimental success achieved using...
In prokaryotes, cognate toxin-antitoxin pairs have long been known, but no three-dimensional structure has available for any given complex from Mycobacterium tuberculosis. Here we report the crystal and activity of a member VapBC family complexes M. The toxin VapC-5 is compact, 150 residues, two domain α/β protein. Bent around VapB-5 antitoxin, 33-residue α-helix. Assays suggest that an Mg-enabled endoribonuclease, inhibited by antitoxin. lack DNase consistent with earlier suggestions...
The L-galactose (Smirnoff-Wheeler) pathway represents the major route to L-ascorbic acid (vitamin C) biosynthesis in higher plants. Arabidopsis thaliana VTC2 and its paralogue VTC5 function as GDP-L-galactose phosphorylases converting L-galactose-1-P, thus catalyzing first committed step of L-ascorbate. Here we report that ascorbate described plants is conserved green algae. Chlamydomonas reinhardtii genome encodes all enzymes required for vitamin C via pathway. We have characterized...
Archaea have a self-assembling proteinaceous surface (S-) layer as the primary and outermost boundary of their cell envelopes. The S-layer maintains structural rigidity, protects organism from adverse environmental elements, yet provides access to all essential nutrients. We determined crystal structure one two “homologous” tandem polypeptide repeats that comprise Methanosarcina acetivorans protein propose high-resolution model for microbial S-layer. molecular features our hexameric...
Cryoelectron microscopy (Cryo-EM) has enabled structural determination of proteins larger than about 50 kDa, including many intractable by any other method, but it largely failed for smaller proteins. Here, we obtain structures small binding them to a rigid molecular scaffold based on designed protein cage, revealing atomic details at resolutions reaching 2.9 Å. We apply this system the key cancer signaling KRAS (19 kDa in size), obtaining four oncogenic mutational variants cryo-EM....
In Escherichia coli, the cold shock response occurs when there is a temperature downshift from 37 degrees C to 15 C, and this characterized by induction of several proteins, including DEAD-box helicase CsdA, during acclimation phase. CsdA involved in variety cellular processes. Our previous studies showed that activity critical for its function cells only proteins were able complement another helicase, RhlE, an RNA chaperone, CspA, cold-inducible exoribonuclease, RNase R. Interestingly,...
Manipulating single molecules and systems of with mechanical force is a powerful technique to examine their physical properties. Applying requires attachment the target molecule larger objects using some sort molecular tether, such as strand DNA. DNA handle often difficult manipulations molecule, which can preclude unstable, hard obtain, and/or large, complex targets. Here we describe method for covalent proteins that simply addition preprepared reagent protein short incubation. The...
Voltage-gated sodium channels initiate the rapid upstroke of action potentials in many excitable tissues. Mutations within intracellular C-terminal sequences specific underlie a diverse set channelopathies, including cardiac arrhythmias and epilepsy syndromes. The three-dimensional structure residues 1777-1882 human NaV1.2 voltage-gated channel has been determined solution by NMR spectroscopy at pH 7.4 290.5 K. ordered extends from Leu-1790 to Glu-1868 is composed four α-helices separated...
Ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO) is a critical yet severely inefficient enzyme that catalyses the fixation of virtually all carbon found on Earth. Here, we report functional metagenomic selection recovers physiologically active RubisCO molecules directly from uncultivated and largely unknown members natural microbial communities. Selection based CO2 -dependent growth in host strain capable expressing environmental deoxyribonucleic acid (DNA), precluding need for pure...
The ESX-1 type VII secretion system is an important determinant of virulence in pathogenic mycobacteria, including Mycobacterium tuberculosis. This complicated molecular machine secretes folded proteins through the mycobacterial cell envelope to subvert host immune response. Despite its role disease very little known about architecture system. study characterizes structures soluble domains two conserved core components – EccB1 and EccD1. periplasmic domain consists 4 repeat a central domain,...
Mycobacterium tuberculosis encodes five gene clusters (ESX-1 to ESX-5) for Type VII protein secretion systems that are implicated in mycobacterial pathogenicity. Substrates the apparatus encoded within and additional loci lack components of apparatus. The best characterized substrates ESX complexes, 1:1 heterodimers ESAT-6 CFP-10, prototypical member has been shown be essential pathogenesis. We have determined structure EsxRS, a homolog EsxGH ESX-3 cluster, at 1.91 Å resolution. EsxRS is...
Beta-2 microglobulin (B2M) is an immune system protein that found on the surface of all nucleated human cells. B2M naturally shed from cell surfaces into plasma, followed by renal excretion. In patients with impaired function, will accumulate in organs and tissues leading to significantly reduced life expectancy quality life. While current hemodialysis methods have been successful managing electrolyte as well small large molecule disturbances arising chronic failure, they shown only modest...
Abstract Protein display systems are powerful techniques used to identify protein molecules that bind with high affinity target proteins of interest. The initial challenge in implementing a system is the construction high‐diversity naïve library. Here, we describe methods generate designed ankyrin repeat (DARPin) library using degenerate oligonucleotides. Specifically described single DARPin module by overlap extension PCR, concatenation restriction enzyme digestion and ligation,...
The expression of heteroligomeric protein complexes for structural studies often requires a special coexpression strategy. reason is that the solubility and proper folding each subunit complex physical association with other subunits complex. genomes pathogenic mycobacteria encode many small complexes, implicated in bacterial fitness pathogenicity, whose characterization may be further complicated by insolubility upon Escherichia coli, most common heterologous host. As fusions have been...
Abstract Ethanol is a widely available carbon compound that can be increasingly produced with net negative balance. Carbon-negative ethanol might therefore provide feedstock for building wider range of sustainable chemicals. Here we show how converted cell free system into acetyl-CoA, central precursor myriad biochemicals, and use the energy stored in to generate ATP, another key molecule important powering biochemical pathways. The ATP generator produces acetone as value-added side product....
Abstract Cancer genomes are rife with genetic variants; one key outcome of this variation is widespread gain-of-cysteine mutations. These acquired cysteines can be both driver mutations and sites targeted by precision therapies. However, despite their ubiquity, nearly all remain unidentified via chemoproteomics; identification a critical step to enable functional analysis, including assessment potential druggability susceptibility oxidation. Here, we pair cysteine chemoproteomics—a technique...
The trace-element oxyanion molybdate, which is required for the growth of many bacterial and archaeal species, transported into cell by an ATP-binding cassette (ABC) transporter superfamily uptake system called ModABC. ModABC consists ModA periplasmic solute-binding protein, integral membrane-transport protein ModB hydrolysis ModC. In this study, X-ray crystal structures from archaeon Methanosarcina acetivorans (MaModA) have been determined in apoprotein conformation at 1.95 1.69 A...