Precise DNA replication is critical for the maintenance of genetic integrity in all organisms. In all three domains
of life, DNA replication starts at a specialized locus, termed as the replication origin, oriC or ORI, and its identification
is vital to understanding the complex replication process. In bacteria and eukaryotes, replication initiates from single
and multiple origins, respectively, while archaea can adopt either of the two modes. The Z-curve method has been
successfully used to identify replication origins in genomes of various species, including multiple oriCs in some archaea.
Based on the Z-curve method and comparative genomics analysis, we have developed a web-based system, Ori-Finder, for
finding oriCs in bacterial genomes with high accuracy. Predicted oriC regions in bacterial genomes are organized into an
online database, DoriC. Recently, archaeal oriC regions identified by both in vivo and in silico methods have also been included
in the database. Here, we summarize the recent advances of in silico prediction of oriCs in bacterial and archaeal
genomes using the Z-curve based method.