[Expanded model of lambda phage ontogeny]

An enlarged threshold model of regulatory system of development of lambda phage (RSDP lambda-2) is built. It includes 15 synthetic blocks of proteins and mRNAs and 4 blocks corresponding to the ontogenetic processes: two-stage replication, integration and exclusion of phage genome, formation of aggregates of regulatory proteins, regulation of bacterial lysis. By means of computer simulation of the RSDP lambda-2 model, the dynamics of concentrations of all main proteins, respective fractions of mRNAs and DNA are described in lytic and lysogenic regimens of phage ontogenesis. The results obtained are in a good agreement with available experimental data. The dependence of portion (%) of lysogenic responses on the mean multiplicity n of phage infection of bacterial culture, is built. This curve has a maximum point in accordance with experimental data of Kourilsky [10].