Title: Self-immolative versatile fluorogenic probes for hydrolase assays

Biography:

Ryszard Ostaszewski was graduated from the Warsaw Technical University in 1985. Since then he has been employed at the Institute of Organic Chemistry, Polish Academy of Sciences, where he obtained his academic degrees (Ph.D. in 1989 under the supervision of Professor Janusz Jurczak, D.Sc. in 1999, and professorship in 2009). He spent his postdoctoral stay at the University of Twente, The Netherlands (1989–1990) and at the University of Zurich, Switzerland, (1994-1995). From 2009 he holds a position of Full Professor at the Institute Of Organic Chemistry PAS. He has published more than 110 papers in reputed journals.

Abstract

Enzyme-activated fluorogenic probes, which visualise enzymatic catalysis to trigger the generation of fluorescence, provide a versatile platform for monitoring biological processes in living cells and in vivo. Early enzyme-activated probes for hydrolase activity assays were primary based on p-nitrophenol esters derivatives.  Although those esters are easily available and applicable low fluorescence of p-nitrophenol releasing during biochemical reactions limits application. Another problem is associated with reversibility of hydrolysis reaction. To overcome those problems a mixed carbonates were proposed for enzymatic assays. Our fist experiments have shoved positive evaluation of mixed carbonates of 4-methyl-7-hydroxycoumarin and various alcohols as a new class of fluorogenic compounds for detecting hydrolytic activities of enzymes.[1] Subsequent studies devoted to enantioselective hydrolase preference assays led to discovery of mixed carbonates of chiral alcohols and 4-methyl and 4-trifluoromethyl coumarins as an efficient tools for screening lipase and esterase enantiopreference.[2] In order to expand the spectrum of enzymes applicable for assays a new type of novel self-immolative probes for enzymatic screening was developed.[3] This system allowed enzymatic screening through a cascade reaction triggered by enzymatic cleavage. The synthesized probes were stable under aqueous conditions and not susceptible to nonspecific reactions. Due to the presence of a carbamate bond, the synthesized compounds are applicable for screening the activity of a wide range of hydrolases, such as lipases, esterases and proteases. In the lecture the general concept devoted to self-immolative fluorogenic probes for detection of hydrolase assays will be presented and discussed on selected examples.