Announcements

Exceptional opportunities are available for highly motivated candidates with strong publication records, regardless of their specific area of expertise. Preferred backgrounds include: molecular biology, algal biology, photosynthesis metabolism, systems biology of microbial metabolism.

A manuscript describing the Rutgers patented spinel OER catalyst LiCo2O4 has been accepted for publication in Energy & Environmental Science (EES), the highest impact journal in the field of energy sciences. This is a joint publication with collaborators from Proton OnSite. This material has been tested in an alkaline exchange membrane electrolyzer.

“Developing chemical processes that will facilitate mass production of economical, environment-friendly solar and wind electricity is one of the biggest challenges of the energy crisis,” said Dismukes.

In a recent paper inThe Journal of Biological Chemistry, researchers at Rutgers University and the University of California, San Diego have

Dr. G. Charles Dismukes

G. Charles Dismukes is a member of the faculties of the Departments of Chemistry & Chemical Biology, and of Molecular Biology & Biochemistry as well as a Principal Investigator of the Waksman Institute.


Research Summary

His research interests focus on biological and chemical methods for renewable solar-based fuel production, photosynthesis, metals in biological systems and tools for investigating these systems. His published works describe the biology and chemistry of oxygen production in natural photosynthetic systems, the synthesis and characterization of bio-inspired catalysts for renewable energy production, the use of microorganisms as cell factories for the production of bio-fuels from renewable sources. He is Principal Investigator of the BioSolarH2 team, a multi-institutional research center focusing on microbial hydrogen. We are pursuing two main goals that address both the fundamental science and practical applications of renewable energy production via I) bio-inspired catalysts for H2 + O2 production via water splitting, and II) sustainable biofuels and CO­2 conversion (hydrogen and liquid fuels).

 

Recent Publications

Qian, X, Kim M K, Kumaraswamy KG, Agarwal A, Lun DS, Dismukes CG.  2016.  Flux balance analysis of photoautotrophic metabolism: Uncovering new biological details of subsystems involved in cyanobacterial photosynthesis. Biochimica et Biophysica Acta (BBA) - Bioenergetics. :-. AbstractWebsite
We have constructed and experimentally tested a comprehensive genome-scale model of photoautotrophic growth, denoted iSyp821, for the cyanobacterium Synechococcus sp. PCC 7002. iSyp821 incorporates a variable biomass objective function (vBOF), in which stoichiometries of the major biomass components vary according to light intensity. The vBOF was constrained to fit the measured cellular carbohydrate/protein content under different light intensities. iSyp821 provides rigorous agreement with experimentally measured cell growth rates and inorganic carbon uptake rates as a function of light intensity. iSyp821 predicts two observed metabolic transitions that occur as light intensity increases: 1) from PSI-cyclic to linear electron flow (greater redox energy), and 2) from carbon allocation as proteins (growth) to carbohydrates (energy storage) mode. iSyp821 predicts photoautotrophic carbon flux into 1) a hybrid gluconeogenesis-pentose phosphate (PP) pathway that produces glycogen by an alternative pathway than conventional gluconeogenesis, and 2) the photorespiration pathway to synthesize the essential amino acid, glycine. Quantitative fluxes through both pathways were verified experimentally by following the kinetics of formation of 13C metabolites from 13CO2 fixation. iSyp821 was modified to include changes in gene products (enzymes) from experimentally measured transcriptomic data and applied to estimate changes in concentrations of metabolites arising from nutrient stress. Using this strategy, we found that iSyp821 correctly predicts the observed redistribution pattern of carbon products under nitrogen depletion, including decreased rates of CO2 uptake, amino acid synthesis, and increased rates of glycogen and lipid synthesis.
Gardner, G, Al-Sharab J, Danilovic N, Go Y B, Ayers KE, Greenblatt M, Dismukes G C.  2015.  Structural Basis for Differing Electrocatalytic Water Oxidation by the Cubic, Layered and Spinel Forms of Lithium Cobalt Oxides. Energy Environ. Sci.. :-. AbstractWebsite
The two polymorphs of lithium cobalt oxide, LiCoO2, present an opportunity to contrast the structural requirements for reversible charge storage (battery function) vs catalysis of water oxidation/oxygen evolution (OER; 2H2O[rightward arrow]O2 + 4H+ + 4e- ). Previously, we reported high OER electrocatalytic activity from nanocrystals of the cubic phase vs. poor activity from the layered phase - the archetypal lithium-ion battery cathode. Here we apply transmission electron microscopy, electron diffraction, voltammetry and elemental analysis under OER electrolysis condition to show that labile Li+ ions (de)intercalate from layered LiCoO2, initiating structural reorganization to the cubic spinel LiCo2O4, in parallel with formation of an active catalytic phase. Comparison of cubic LiCoO2 (50nm) to iridium (5 nm) nanoparticles for OER catalysis (commercial benchmark) in basic and neutral electrolyte reveals excellent performance in terms of Tafel slope (48 mV dec-1), overpotential ([small eta] =  420 mV @ 10 mA cm-2 at pH = 14), Faradic yield (100%) and OER stability (no loss in 14 hours). The inherent OER activity of cubic LiCoO2 and spinel LiCo2O4 is attributable to their [Co4O4]n+ cubane structural units, which provides lower oxidation potential to Co4+ and lower inter-cubane hole mobility. By contrast, the layered phase which lacks cubanes exhibits extensive intra-planar hole delocalization which entropically disfavors the four electron/hole concerted OER reaction.
McNeely, K, Kumaraswamy KG, Guerra T, Bennette N, Ananyev GM, Dismukes CG.  2014.  Metabolic switching of central carbon metabolism in response to nitrate: Application to autofermentative hydrogen production in cyanobacteria.. Journal of biotechnology. 182-183:83-91. Abstract
Nitrate removal from culture media is widely used to enhance autofermentative hydrogen production in cyanobacteria during dark anaerobiosis. Here we have performed a systematic inventory of carbon and nitrogen metabolites, redox pools, and excreted product fluxes which show that addition of nitrate to cultures of Synechococcus sp. PCC 7002 has no influence on glycogen catabolic rate, but shifts the distribution of excreted products from predominantly lactate and H2 to predominantly CO2 and nitrite, while increasing the total consumption of intracellular reducing equivalents (mainly glycogen) by 3-fold. Together with LC-MS derived metabolite pool sizes these data show that glycogen catabolism is redirected from the upper-glycolytic (EMP) pathway to the oxidative pentose phosphate (OPP) pathway upon nitrate addition. This metabolic switch in carbon catabolism is shown to temporally correlate with the pyridine nucleotide redox-poise (NAD(P)H/NAD(P)(+)) and demonstrates the reductant availability controls H2 evolution in cyanobacteria.
Carrell TG, Smith PF, Dennes J, Dismukes CG.  2014.  Entropy and enthalpy contributions to the kinetics of proton coupled electron transfer to the Mn4O4(O2PPh2)6 cubane.. Physical chemistry chemical physics : PCCP. 16(24):11843-7. Abstract
The dependence of rate, entropy of activation, and ((1)H/(2)H) kinetic isotope effect for H-atom transfer from a series of p-substituted phenols to cubane Mn4O4L6 (L = O2PPh2) () reveals the activation energy to form the transition state is proportional to the phenolic O-H bond dissociation energy. New implications for water oxidation and charge recombination in photosystem II are described.