The objective of ARCHPOL is to discover novel functional DNA polymerases in hyperthermophilic archaea and to examine the potential impact of relevant damaged nucleic acids onto their intrinsic properties. This interest is sustained by the limited number of DNA polymerases identified to date in the genome of the hyperthermophilic model, P. abyssi, posing the intriguing question of how this microorganism evolve to deal with a specific threshold of DNA damage without affecting cell growth and viability. Despite efficient DNA repair strategies employed to remove damaged nucleic acids, some of them persist. Palud. A et al recently published that DNA polymerases from P. abyssi develop unique and efficient features to counteract residual DNA lesions. In ARCHPOL, the functional analyses of conventional and damaged-induced DNA polymerases will be detailed in the presence of relevant damaged nucleic acids. This project aims at giving a clear picture of the involvement of DNA polymerases in damage tolerance in hyperthermophilic archaea that may provide useful information to further refined model of genomic maintenance in all living organisms. Unique and innovative methods will be applied to discover novel DNA polymerases and to identify the types and occurrence of damaged nucleic acids. A gas-lift bioreactor which offers the possibility to inflict genotoxic stresses will be used to produce the P. abyssi biomass. The types and rates of damaged nucleic acids will be assessed by cutting-edge analytic methods. Identification and captured of novel DNA polymerases will be obtained by implemented and original techniques. When required, relevant DNA damage will be introduced into DNA template and functional characterization of appropriate DNA polymerases will be investigated. As a consequence from basic fundamental research, ARCHPOL plans to develop valuable biochemical properties from P. abyssi polymerases that could be applied to various biotechnological applications. The current tendency in Polymerase chain Reaction (PCR) technology is to discover thermostable polymerases with broadened substrate spectra that could find applications in forensics and paleogenetics. In order to optimize the chances of success of ARCHPOL, which combines scientific and technological objectives, a highly competent and complementary team will be unified.