Bacterial microcompartment shell protein EutL

UniProtKB accession:  P76541

Grouped By:  Matching UniProtKB accession

UniProtKB description:  A component of the bacterial microcompartment (BMC) shell dedicated to ethanolamine degradation (Probable). Two crystal forms have been seen; a form with a closed central pore that has 3 very small (1.1-2.2 Angstroms) channels per trimer lined by acidic and aromatic residues (PubMed:19451619, PubMed:20044574). A form with a large central pore (8-12 Angstroms) has also been seen; this is probably a functional pore which allows molecules to enter and exit the BMC in a selective, gated manner (PubMed:20044574, PubMed:20851901). Another group only sees the central pore in the presence of Zn(2+); soaking crystals in ZnCl(2) leads to dramatic conformational changes that open a central pore of about 12 Angstroms. Whether Zn(2+) binding is physiologically relevant is unclear, however it suggests a gating mechanism exists (PubMed:20851901). Ethanolamine-binding by the small channels has been hypothesized to stabilize the EutL central pore in a closed (non-transporting) state. An open pore is thought to be large enough to transport ATP and/or cobalamin (By similarity).