Phase I will investigate the design and synthesis of catalase-activated chemiluminescent substrates for future use in DNA sequencing with chemiluminescent detection. The viability of DNA sequence imaging using a novel alkaline phosphatase, labile dioxetane disodium 3-(4-methoxyspiro[l ,2-dioxetane-3,2-tricyclo[3.3.1.1.3s7ldecan]-4yl)phenyl phosphate (AMPPD), as a chemiluminescent substrate has been successfully demonstrated. Increasing catalytic turnover would further improve detection levels in this system. Catalase, the enzyme responsible for peroxide decomposition in mammalian and nonmammalian aerobic cells, has such potential with a turnover rate a thousand times faster than that of alkaline phosphatase.Tropix, Inc., will initially develop three types of catalase-activated substrates. These dioxetanes will be synthesized and investigated for catalase reactivity, manifested as demethylation,decarboxylation, or oxygenation. If the expected enzymic transformation occurs, a moderately stable charge transfer species will be generated that fragments to adamantanone and an excited-state aryl fluorophore, subsequently emitting light upon decaying to the ground state. Once suitable catalase-labile chemiluminescent substrates have been obtained, Phase II will focus on incorporating these substrates in a chemiluminescence-based DNA sequencing method.Awardee's statement of the potential commercial applications of the research:Tropix, Inc., will design and synthesize a new generation of catalaseactivated chemiluminescent substrates for use in chemiluminescent-based DNA sequencing. The advantages of this technology are:(1) improved detection sensitivity,(2) stable chemiluminescent substrates,(3) elimination of lengthy imaging procedures,(4) replacement of radioactive probes, and(5) amplified instrumentation.National Center for Human Genome Research (NCHGR)
