Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules).

Enables the facilitated diffusion of an ion (by an energy-independent process) by passage through a transmembrane aqueous pore or channel without evidence for a carrier-mediated mechanism. May be either selective (it enables passage of a specific ion only) or non-selective (it enables passage of two or more ions of same charge but different size).

Enables the transfer of an ion from one side of a membrane to the other.

Enables the transfer of substances, sized less than 1000 Da, from one side of a membrane to the other. The transmembrane portions of porins consist exclusively of beta-strands which form a beta-barrel. They are found in the outer membranes of Gram-negative bacteria, mitochondria, plastids and possibly acid-fast Gram-positive bacteria.

Enables the transfer of substances, sized less than 1000 Da, from one side of a membrane to the other. The transmembrane portions of porins consist exclusively of beta-strands which form a beta-barrel. They are found in the outer membranes of Gram-negative bacteria, mitochondria, plastids and possibly acid-fast Gram-positive bacteria.

Interacting selectively and non-covalently with an identical protein or proteins.

Interacting selectively and non-covalently with an identical protein or proteins.

Enables the directed movement of a xenobiotic from one side of a membrane to the other. A xenobiotic is a compound foreign the organim exposed to it. It may be synthesized by another organism (like ampicilin) or it can be a synthetic chemical.

Enables the transfer of a colicin from one side of a membrane to the other. Colicins are a group of antibiotics produced by E. coli and related species that are encoded by a group of naturally occurring plasmids, e.g. Col E1.

Interacting selectively and non-covalently with a protein N-terminus, the end of any peptide chain at which the 2-amino (or 2-imino) function of a constituent amino acid is not attached in peptide linkage to another amino-acid residue.

Interacting selectively and non-covalently with a disordered domain of a protein.

Enables the transfer of substances, sized less than 1000 Da, from one side of a membrane to the other. The transmembrane portions of porins consist exclusively of beta-strands which form a beta-barrel. They are found in the outer membranes of Gram-negative bacteria, mitochondria, plastids and possibly acid-fast Gram-positive bacteria.