Enzymatic Reaction at the Single Molecule Level Moisés Santillán∗ Centro de Investigación y Estudios Avanzados del IPN, Unidad Monterrey, Parque de Investigación e Innovación Tecnológica, 66600 Apodaca NL, MÉXICO Abstract In this work we study, at the single molecular level, the thermodynamic and dynamic characteristics of an enzymatic reaction comprising a rate limiting step. We investigate ho...

The steady-state kinetics of the reaction catalyzed by glycogen phosphorylase b from rabbit skeletal muscles has been studied in a wide range of the concentrations of adenosine 5 ′ -monophosphate in the direction of glycogen synthesis under the conditions of saturation of the enzyme by glycogen. The kinetic model has been proposed to describe the bell-shaped dependence of the initial rate of th...

DNA can be concatenated by hybridization of DNA fragments with protruding single-stranded termini. DNA cleavage occurring at a nucleotide containing a DNA base analogue is a useful method to obtain DNA with designed protruding termini. Here, we report a novel non-enzymatic DNA cleavage reaction for DNA concatenation. We found that DNA is cleaved at a nucleotide containing 5-ethynyluracil in a m...

An enzymatic synthesis of sphingomyelin, N-acylsphingosylphosphorylcholine, was demonstrated by Sribney and Kennedy to occur via a reaction between ceramide (Nacylsphingosine) and CDP-choline. They indicated in this study that N-acyl derivatives of fhreo-sphingosine were far superior to the eryfhro derivatives as acceptors for the phosphorylcholine moiety. We have repeated these enzymatic exper...

In this work, a lipase-catalyzed selective enzymatic hydrolysis of the borage oil was carried out using commercial enzymes and native crude enzymatic extract from Brazil as biocatalysts for the reaction. Two crude enzymatic extracts home-produced and three commercial lipases were screened for concentrating γlinolenic acid of the triacylglycerols in unhydrolyzed acylglycerols. The kinetics of en...

An automated procedure is presented for the enzymatic determination of serum uric acid on both the AutoAnalyzer and the Robot Chemist. The procedure measures as the neocuproine complex, the difference in the amount of Cu+ formed by reaction of a Cu++ aIkanoIamine buffered solution with serum uric acid under precisely controlled conditions before and after uricase treatment of the serum. The dif...

Fifty years ago, the group of Tony Mathias and Bob Rabin at University College London deduced the first mechanism for catalysis by an enzyme, ribonuclease [Findlay, D., Herries, D. G., Mathias, A. P., Rabin, B. R., and Ross, C. A. (1961) Nature 190, 781-784]. Here, we celebrate this historic accomplishment by surveying knowledge of enzymology and protein science at that time, facts that led to ...

The preparation and characterization of UV-cured polyurethane-based materials for the mild inclusion immobilization of enzymes was investigated. Full curing of the polymer precursor/enzyme solution mixture was realized by a short irradiation with UV-light at ambient temperatures. The included aqueous enzyme solution remains highly dispersed in the polymer material with an even size distribution...

Since the discovery of enzymes as biological catalysts, study of their enormous catalytic power and exquisite specificity has been central to biochemistry. Nevertheless, there is no universally accepted comprehensive description. Rather, numerous proposals have been presented over the past half century. The difficulty in developing a comprehensive description for the catalytic power of enzymes ...