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6arc

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Monoclinic EutL - structure determined from merged "Group 1" data

Structural highlights

6arc is a 3 chain structure with sequence from Clostridium perfringens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 1.9Å
Ligands:	,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

EUTL_CLOPE A component of the bacterial microcompartment (BMC) shell dedicated to ethanolamine degradation. May be involved in cofactor diffusion across the BMC (Probable). Cobalamin is covalently bound to 1 subunit of the trimer on the concave (lumenal) face in a closed pore conformation; whether this is physiologically relevant is unclear (PubMed:25484204). The closed form has 3 very narrow channels (1.3 Angstrom at their narrowest) per trimer lined by acidic and aromatic residues; 2 ethanolamine molecules can bind in each channel, on either side of the constriction. Does not bind acetate, ethanol or acetyl phosphate, all of which are small molecules involved in ethanolamine metabolism (PubMed:25752492). Ethanolamine-binding 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 (Probable).^[1] ^[2] ^[3] ^[4] ^[5]

References

↑ Thompson MC, Crowley CS, Kopstein J, Bobik TA, Yeates TO. Structure of a bacterial microcompartment shell protein bound to a cobalamin cofactor. Acta Crystallogr F Struct Biol Commun. 2014 Dec 1;70(Pt 12):1584-90. doi:, 10.1107/S2053230X1402158X. Epub 2014 Nov 14. PMID:25484204 doi:http://dx.doi.org/10.1107/S2053230X1402158X
↑ Thompson MC, Cascio D, Leibly DJ, Yeates TO. An allosteric model for control of pore opening by substrate binding in the eutl microcompartment shell protein. Protein Sci. 2015 Mar 9. doi: 10.1002/pro.2672. PMID:25752492 doi:http://dx.doi.org/10.1002/pro.2672
↑ Thompson MC, Crowley CS, Kopstein J, Bobik TA, Yeates TO. Structure of a bacterial microcompartment shell protein bound to a cobalamin cofactor. Acta Crystallogr F Struct Biol Commun. 2014 Dec 1;70(Pt 12):1584-90. doi:, 10.1107/S2053230X1402158X. Epub 2014 Nov 14. PMID:25484204 doi:http://dx.doi.org/10.1107/S2053230X1402158X
↑ Thompson MC, Cascio D, Leibly DJ, Yeates TO. An allosteric model for control of pore opening by substrate binding in the eutl microcompartment shell protein. Protein Sci. 2015 Mar 9. doi: 10.1002/pro.2672. PMID:25752492 doi:http://dx.doi.org/10.1002/pro.2672
↑ Thompson MC, Cascio D, Yeates TO. Microfocus diffraction from different regions of a protein crystal: structural variations and unit-cell polymorphism. Acta Crystallogr D Struct Biol. 2018 May 1;74(Pt 5):411-421. doi:, 10.1107/S2059798318003479. Epub 2018 Apr 24. PMID:29717712 doi:http://dx.doi.org/10.1107/S2059798318003479