The main project purpose is to investigate the fundamental physiological state of M. tuberculosis (MTB) during the infection and the mycobacterial response within the infected host tissue, human lung. High-throughput proteomic analysis of MTB cells will be involved to solve this problem. The description of pattern of proteins expressed in MTB cells extracted directly from clinical material of patients with tuberculosis defines the main novelty of the given project. Undoubtedly, the intermediate project results describing the features of MTB strains proteome in vitro will also be essential for the global scientific community.