A5054586479- Microbial metabolism and enzyme function
- Metal-Catalyzed Oxygenation Mechanisms
- Microbial Metabolic Engineering and Bioproduction
- Porphyrin Metabolism and Disorders
- Biofuel production and bioconversion
- Algal biology and biofuel production
- Chemical synthesis and alkaloids
- Phosphodiesterase function and regulation
- Microbial bioremediation and biosurfactants
- Enzyme Structure and Function
- Metalloenzymes and iron-sulfur proteins
- Crystal structures of chemical compounds
- Lipid Membrane Structure and Behavior
- Mass Spectrometry Techniques and Applications
- Photosynthetic Processes and Mechanisms
- Pancreatic function and diabetes
- Erythrocyte Function and Pathophysiology
- Hydrocarbon exploration and reservoir analysis
- Coagulation, Bradykinin, Polyphosphates, and Angioedema
- Folate and B Vitamins Research
- Microbial Fuel Cells and Bioremediation
- Receptor Mechanisms and Signaling
- Enzyme Catalysis and Immobilization
- Synthesis and Catalytic Reactions
- Biochemical Acid Research Studies
Northwestern University
2016-2022
University of California, Los Angeles
2013-2015
Metabolic engineering of photosynthetic microorganisms such as cyanobacteria for the production fuels or chemicals is challenging, particularly when pathway involves oxygen-sensitive enzymes. We have previously designed a coenzyme A (CoA) dependent n-butanol biosynthesis tailored to metabolic physiology cyanobacterium Synechococcus elongatus PCC 7942 by incorporating an ATP driving force and kinetically irreversible trap. However, one enzymes involved, CoA-acylating butyraldehyde...
Using iron to generate a copper ligand Many microbial enzymes are metal-dependent, and the microbe must acquire scarce metals from environment. Microbes that use methane as carbon source have copper-dependent enzyme oxidizes methane. Peptides known methanobactins (Mbns) by using pair of ligands comprising nitrogen-containing ring an adjacent thioamide. Kenney et al. describe biosynthetic machinery adds copper-binding groups precursor peptide. This involves complex two homologs: MbnB, member...
Abstract Aerobic methane oxidation is catalyzed by particulate monooxygenase (pMMO), a copper-dependent, membrane metalloenzyme composed of subunits PmoA, PmoB, and PmoC. Characterization the copper active site has been limited challenges in spectroscopic analysis stemming from presence multiple binding sites, effects detergent solubilization on activity crystal structures, lack heterologous expression system. Here we utilize nanodiscs coupled with native top-down mass spectrometry (nTDMS)...
Particulate methane monooxygenase (pMMO) is a copper-dependent integral membrane metalloenzyme that converts to methanol in methanotrophic bacteria. Studies of isolated pMMO have been hindered by loss enzymatic activity upon its removal from the native membrane. To characterize membrane-like environment, we reconstituted pMMOs Methylococcus (Mcc.) capsulatus (Bath) and Methylomicrobium (Mm.) alcaliphilum 20Z into bicelles. Reconstitution bicelles recovers oxidation lost detergent...
Significance Copper is central to the metabolism of methanotrophs, methane-oxidizing bacteria that are interest because their potential applications in bioremediation and bioconversion processes. Methanotrophs convert methane methanol using particulate monooxygenase (pMMO), a copper-dependent, membrane-bound enzyme. To fulfill pMMO’s high requirement for copper, methanotrophs secrete re-internalize methanobactin, peptide-derived, copper-chelating natural product (CuMbn). Here we characterize...
Methane-oxidizing microbes catalyze the oxidation of greenhouse gas methane using copper-dependent enzyme particulate monooxygenase (pMMO). Isolated pMMO exhibits lower activity than whole cells, however, suggesting that additional components may be required. A homolog, ammonia (AMO), converts to hydroxylamine in ammonia-oxidizing bacteria (AOB) which produce another potent gas, nitrous oxide. Here we show PmoD, a protein encoded within many pmo operons is homologous AmoD proteins AOB amo...
Developing small-molecule (SM) therapeutics that target membrane proteins (MPs) is often challenging, because few biophysical methods can handle the detergents required to maintain stability. Here, we report a surface plasmon resonance (SPR)-based methodology enables characterization of interactions between SMs and an ion channel receptor (MP1) in complex with stabilizing antibody fragment (Fab) surfactant. Briefly, stable MP1-Fab was formed by coimmobilizing MP1 anti-MP1-Fab within hydrogel...
Triosephosphate isomerase (TPI) performs the 5th step in glycolysis, operates near limit of diffusion, and is involved "moonlighting" functions. Its dimer was found singly phosphorylated at Ser20 (pSer20) human cells, with this post-translational modification (PTM) showing context-dependent stoichiometry loss under oxidative stress. We generated synthetic pSer20 proteoforms using cell-free protein synthesis that showed enhanced TPI activity by 4-fold relative to unmodified TPI. Molecular...
Industrial biotechnology provides an efficient, sustainable solution for chemical production. However, designing biochemical pathways based solely on known reactions does not exploit its full potential. Enzymes are to accept non-native substrates, which may allow novel, advantageous reactions. We have previously developed a computational program named Biological Network Integrated Computational Explorer (BNICE) predict promiscuous enzyme activities and design synthetic pathways, using...
Methanotrophic bacteria use methane, a potent greenhouse gas, as their primary source of carbon and energy. The first step in methane metabolism is its oxidation to methanol. In mostly all methanotrophs, this chemically challenging reaction catalyzed by particulate monooxygenase (pMMO), copper‐dependent integral membrane enzyme. Many methanotrophs acquire copper for pMMO secreting small ribosomally produced, post‐translationally modified natural products called methanobactins. Each species...