Question

Select the odd one our w.r.t. porins.

• A. Not associated with the inner membrane of plastids
• B. Associated with the outer membrane of mitochondria
• C. Found in outer membrane of gram positive bacteria
• D. Allow movement of low molecular weight hydrophilic substances

Answer 1

The correct option is A Not associated with the inner membrane of plastids

Porins are beta barrel proteins that cross a cellular membrane and act as a pore, through which molecules can diffuse. Unlike other membrane transport proteins, porins are large enough to allow passive diffusion, i.e., they act as channels that are specific to different types of molecules. Porins from non-green plastids and from the outer mitochondrial membrane were re- constituted into planar lipid bi-layers. The proteins showed high pore-forming activities and similar single- channel conductance. So, the correct option is "Not associated with the inner membrane of plastids".