Competition between Chlamydia psittaci and L cells for host isoleucine pools: a limiting factor in chlamydial multiplication.

摘要: L cells (mouse fibroblasts) supported the multiplication of obligately intracellular parasitic bacterium Chlamydia psittaci (strain 6BC) when incubated in fresh growth medium (medium 199 + 5% fetal calf serum). When supernatant from a 24-h-old culture uninfected (24-h used medium), did not divide and infected provide an adequate environment for C. psittaci, which persisted noninfectious latent state within host cells. The failure both chlamydiae to resulted overall reduction rate protein synthesis by parasite brought about insufficiency essential amino acid isoleucine 24-h medium. concentration required activate minimal also minimally stimulated divide. addition cycloheximide activated chlamydial infection because it incorporation protein-derived into protein. results suggest that L-cell compete soluble pool cell is capable sequestering its own biosynthetic needs only rises above level maintain hose stationary state. Extrapolation obtained with cell-C. model system natural infections discussed. Images