A5102812475- Lipid Membrane Structure and Behavior
- Enzyme Structure and Function
- Protein Structure and Dynamics
- Bacterial Genetics and Biotechnology
- RNA and protein synthesis mechanisms
- Porphyrin Metabolism and Disorders
- Ion channel regulation and function
- Surfactants and Colloidal Systems
- Protein purification and stability
- Mass Spectrometry Techniques and Applications
- Photoreceptor and optogenetics research
- Iron Metabolism and Disorders
- Nuclear Structure and Function
- Photosynthetic Processes and Mechanisms
- Folate and B Vitamins Research
- Spectroscopy and Quantum Chemical Studies
- Antibiotic Resistance in Bacteria
- Advanced biosensing and bioanalysis techniques
- Ion Transport and Channel Regulation
- Cellular transport and secretion
- Metabolomics and Mass Spectrometry Studies
- Trace Elements in Health
- Medical Imaging Techniques and Applications
- Boron Compounds in Chemistry
- Glycosylation and Glycoproteins Research
University of Virginia
2011-2024
IPG Photonics (United States)
2024
Royal Hallamshire Hospital
2015
University of California, San Francisco
1995-2010
Northwestern University
1995-1998
University of California, Irvine
1991-1992
Carnegie Mellon University
1986-1989
In Gram-negative bacteria, the import of essential micronutrients across outer membrane requires a transporter, an electrochemical gradient protons inner membrane, and protein complex (ExbB, ExbD, TonB) that couples proton-motive force to transporter. The TonB binds directly conserved region, called Ton-box, We solved structure cobalamin transporter BtuB in with C-terminal domain TonB. contrast its conformations absence TonB, Ton-box forms β strand is recruited existing sheet which...
Cells of Escherichia coli take up vitamin B(12) (cyano-cobalamin [CN-Cbl]) and iron chelates by use sequential active transport processes. Transport CN-Cbl across the outer membrane its accumulation in periplasm is mediated TonB-dependent transporter BtuB. cytoplasmic (CM) requires BtuC BtuD proteins, which are most related sequence to transmembrane ATP-binding cassette proteins periplasmic permeases for iron-siderophore transport. Unlike genetic organization permeases, a candidate gene...
Posttranslational lipidation provides critical modulation of the functions some proteins. Isoprenoids (i.e., farnesyl or geranylgeranyl groups) are attached to cysteine residues in proteins containing C-terminal CAAX sequence motifs (where A is an aliphatic residue and X any residue). Isoprenylation followed by cleavage AAX amino acid and, cases, additional proteolytic cuts. We determined crystal structure protease Ste24p, a zinc metalloprotease catalyzing two steps maturation yeast mating...
Abstract Outer membrane protein A (OmpA) of Escherichia coli is a β‐barrel that unfolds in 8 M urea to random coil. OmpA refolds upon dilution the presence certain detergents or lipids. To examine minimal requirements for secondary and tertiary structure formation proteins, folding was studied as function hydrophobic chain length, chemical polar headgroup, concentration large array amphiphiles. folded only above critical length apolar determined by circular dichroism spectroscopy SDS‐PAGE...
Abstract TonB‐dependent outer membrane transporters (TBDTs) transport organometallic substrates across the membranes of Gram‐negative bacteria. Currently, structures four different TBDTs have been determined by X‐ray crystallography. TBDT consist a 22‐stranded β‐barrel enclosing hatch domain. Structure‐based sequence alignment these indicates presence highly conserved motifs in both and barrel domains. The two domains are always close proximity to each other interact. We analyzed very large...