Biotechnology for production of fuels,chemicals, and materials from biomass

Applied Biochemistry and Biotechnology - Biological systems can convert renewable resources, including lignocellulosic biomass, starch crops, and carbon dioxide, into fuels, chemicals, and...     

The influence of metal cluster size on adsorption energies: CO adsorbed on Au clusters supported on TiO2

Infrared reflection absorption spectroscopy (IRAS) has been used to study CO adsorption on Au clusters ranging in size from 1.8 to 3.1 nm, supported on TiO(2). The adsorbed CO vibrational frequency blue-shifts slightly (approximately 4 cm(-)(1)) compared to that adsorbed on bulk Au, whereas the heats of adsorption (-DeltaH(ads)) increase sharply with decreasing cluster size, from 12.5 to 18.3 kcal/mol.     

Characterization of dynamic and steady-state protein phosphorylation using a fluorescent phosphoprotein gel stain and mass spectrometry

Protein phosphorylation plays a vital role in the regulation of most aspects of cellular activity, being key to propagating messages within signal transduction pathways and to modulating protein function. Pro-Q Diamond phosphoprotein gel stain is suitable for the fluorescence detection of phosphoserine-, phosphothreonine-, and phosphotyrosine-containing proteins directly in sodium dodecyl sulfate (SDS)-polyacrylamide gels. The technology is especially appropriate for profiling steady-state and dynamic phosphorylation on a proteome-wide scale, as demonstrated through detection of the native phosphorylation of cardiac mitochondrial phosphoproteins and changes in this profile arising from the activity of a protein kinase. For example, Pro-Q Diamond phosphoprotein gel stain was employed to demonstrate that among the 46 subunits of the mitochondrial respiratory chain complex, NADH:ubiquinone oxidoreductase (complex I), a 42 kDa subunit is phosphorylated in the steady-state. However, exposure of mitochondria to cAMP-dependent protein kinase increases phosphorylation of this 42 kDa subunit and results in de novo phosphorylation of an 18 kDa subunit as well. Since Pro-Q Diamond dye binds to phosphorylated residues noncovalently, the staining technology is fully compatible with modern microchemical analysis procedures, such as peptide mass profiling by matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry and post-source decay analysis of peptide phosphorylation.     

Cyclophosphamides from aminosugars and aminonucleosides

Condensation of bis-(2-chloroethyl)phosphoramidic dichloride with 3′-amino-3′-deoxy-N,N-dimethyladenosine afforded the 2′,3′-cyclicphosphorodiamidate (III). By an improved synthesis, methyl 3-amino-3-deoxy-β-D-ribofuranoside was obtained as a model compound for conversion to the analogous 2,3-cyclicphosphorodiamidate (XII). Existence of the latter as two diastereomers due to phosphorus asymmetry was shown by nmr analysis, using comparison with the 5-(O-p-nitrobenzoate) (XIII) as a basis for assignments.     

Rotavap simulation and the estimation of boiling points

A Java applet that predicts solute losses during evaporation from a binary or ternary mixture has been developed which gives good agreement with experiment and can be used to estimate the boiling points of solutes, making use of information which is often collected and then discarded (http://www.ch.cam.ac.uk/magnus/rotavap/).     

Synthesis of 2-amino-4-pyrimidinones from resin-bound guanidines prepared using bis(allyloxycarbonyl)-protected triflylguanidine

We have synthesized novel heterocyclic compounds from resin-bound guanidines. For this purpose, an amine immobilized on a solid support was acylated with protected amino acids. Following the deprotection, the liberated amines were guanidinylated utilizing a new member of the family of diurethane-protected triflyl guanidine reagents, N,N'-bis(allyloxycarbonyl)-N' '-triflylguanidine. The deprotected guanidines were subsequently regioselectively cyclized with beta-keto esters yielding novel compounds containing heterocyclic structures in high purities.