Obiettivo In recent years obvious progress has been made in understanding the molecular mechanisms behind the catalytic activity, stability and specificity of enzymes in aqueous solutions. At the same time, rapid developments in biotechnology have created an interest in the behaviour of proteins under conditions previously regarded as detrimental. Systems with a high content of organic solvents are among the most attractive. Development of the principles of enzyme function and stability in systems with organic solvents of different types (water-miscibility, hydrophobicity, polarity) may be also helpful in modelling the behaviour of enzymes in vivo, where their environment is often far from simply aqueous. The direct use of enzymes in these systems is hampered by the phenomenon of protein denaturation by organic solvents, discovered several decades ago but still not completely understood. The project incorporates two major tasks: to find some common principles governing the behaviour of enzymes in organic solvent systems and to compare them with the established mechanisms regulating activity and stability in aqueous solutions; to apply the approaches recommended as best for thermostabilisation of proteins and develop new approaches to increase enzyme stability in organic solvent systems, and to study the possibilities of regulating enzyme activity and stability in such systems. A study on enzymes and their complexes in two kinds of systems with organic solvents: homogeneous solutions in mixtures with water-miscible solvents and suspensions in immiscible solvents. Catalytic activity, specificity and stability of enzymes will be the main properties studied; where necessary, enzymological tests will be done together with complementary structural studies by physical methods. Different possibilities of regulating the structure, activity and stability of enzymes by the nature of the organic solvents will be tested; in the systems with low water content, special attention will be paid to the effects of water activity on the enzyme function and stability. Catalytic activity and stability of the enzymes isolated from the thermophiles will be studied both in solutions and suspensions with organic solvents, in comparison with mesophilic counterparts. An attempt will be made to alter the catalytic properties and stability of enzymes by structural changes made by targeted chemical modification of protein functional groups. Another approach is opened up by a recently discovered ability of both native and modified enzymes to form non-covalent complexes with polyelectrolytes that are stable in organic solvents. Two morphologically and structurally different systems will be tested: electrostatic complexes of enzymes with polyelectrolytes and enzymes entrapped into microheterogeneous polymeric reversed micelles. On the basis of some preliminary data with both systems, high catalytic activity and stability of the enzyme included into polymeric particles are to be expected. Programma(i) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Argomento(i) 42 - Physical Chemical Biology Invito a presentare proposte Data not available Meccanismo di finanziamento Data not available Coordinatore University of Strathclyde Contributo UE Nessun dato Indirizzo Royal College Building 204 George Street G1 1XW Glasgow Regno Unito Mostra sulla mappa Costo totale Nessun dato Partecipanti (5) Classifica in ordine alfabetico Classifica per Contributo UE Espandi tutto Riduci tutto Dublin City University Irlanda Contributo UE Nessun dato Indirizzo Dublin 9 Mostra sulla mappa Costo totale Nessun dato Moscow State University M.V. Lomonosov Russia Contributo UE Nessun dato Indirizzo 119899 Moscow Mostra sulla mappa Costo totale Nessun dato NATIONAL RESEARCH COUNCIL OF ITALY Italia Contributo UE Nessun dato Indirizzo Via Marconi 10 80125 NAPOLI Mostra sulla mappa Costo totale Nessun dato National Academy of Sciences of Ukraine Ucraina Contributo UE Nessun dato Indirizzo 286021 Vinnitsa Mostra sulla mappa Costo totale Nessun dato Russian Academy of Sciences Russia Contributo UE Nessun dato Indirizzo 117977 Moscow Mostra sulla mappa Costo totale Nessun dato
