CpnT - Outer Membrane Channel Protein CpnT
Outer membrane Channel Proteins
CpnT is expressed by the Mycobacterium tuberculosis. CpnT has a dual function in uptake of nutrients and induction of host cell death.
Topology and Function:
CpnT consists of two domains. The oligomeric N-terminal domain (NTD) forms an outer membrane channel and is required for efficient glycerol uptake. The toxic C-terminal domain (CTD) is cleaved and secreted and acts as a glycohydrolase, which hydrolyzes the essential cellular coenzyme NAD+ in the cytosol of infected macrophages, leading to necrotic host cell death. Both functions are required for survival, replication and cytotoxicity of M.tuberculosis in macrophages.