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BtuB
From Proteopedia
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== Function == | == Function == | ||
| - | '''BtuB''' is an outer membrane receptor found in a variety of bacteria, such as ''E. coli''. BtuB transports vitamin B12 across the membrane of gram-negative bacteria. The transport is achieved with high affinity by the collaboration of BtuB and the periplasmic protein TonB. | + | '''BtuB'''or '''vitamin B12 receptor''' or '''outer membrane cobalamin transporter''' is an outer membrane receptor found in a variety of bacteria, such as ''E. coli''. BtuB transports vitamin B12 across the membrane of gram-negative bacteria. The transport is achieved with high affinity by the collaboration of BtuB and the periplasmic protein TonB. <ref>PMID:14499604</ref> As an essential receptor for the cell that is constitutively expressed, it is an ideal target to be parasitized, a feature exploited by a variety of proteins such as [[Colicin]]s. |
== Structural highlights == | == Structural highlights == | ||
| - | BtuB depends on the presence of Ca+2 ions for high affinity binding of cobalamin (a form of vitamin B12). The Ca+2 ions are coordinated to several Asp side chains. | + | BtuB depends on the presence of Ca+2 ions for high affinity <scene name='43/439262/Cv/6'>binding of cobalamin (a form of vitamin B12)</scene>. The <scene name='43/439262/Cv/7'>Ca+2 ions are coordinated to several Asp side chains</scene>.<ref>PMID:20816073</ref> |
==3D structure of BtuB== | ==3D structure of BtuB== | ||
| + | [[BtuB 3D structures]] | ||
| - | + | </StructureSection> | |
| - | [[2guf]], [[1nqe]], [[1nqf]] – EcBtuB – ''Escherichia coli''<br /> | ||
| - | [[3m8b]], [[3rgm]], [[3rgn]] – EcBtuB (mutant) <br /> | ||
| - | [[3m8d]] - EcBtuB (mutant) + cyanocobalamin<br /> | ||
| - | [[1nqh]] - EcBtuB + cyanocobalamin + Ca<br /> | ||
| - | [[2ysu]] - EcBtuB + Colicin E2 receptor binding domain<br /> | ||
| - | [[1ujw]] - EcBtuB + Colicin E3 receptor binding domain<br /> | ||
| - | [[2gsk]] - EcBtuB + TonB C-terminal<br /> | ||
| - | [[1nqg]] - EcBtuB + Ca<br /> | ||
| - | [[2bto]] – PdBtuBA + thioredoxin – ''Prosthecobacter dejongeii''<br /> | ||
| - | [[2btq]] – PdBtuBA + PdBtuBB | ||
| + | == References == | ||
| + | <references/> | ||
[[Category:Topic Page]] | [[Category:Topic Page]] | ||
Current revision
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References
- ↑ Chimento DP, Kadner RJ, Wiener MC. The Escherichia coli outer membrane cobalamin transporter BtuB: structural analysis of calcium and substrate binding, and identification of orthologous transporters by sequence/structure conservation. J Mol Biol. 2003 Oct 3;332(5):999-1014. PMID:14499604 doi:http://dx.doi.org/10.1016/S0022283603009975
- ↑ Freed DM, Horanyi PS, Wiener MC, Cafiso DS. Conformational exchange in a membrane transport protein is altered in protein crystals. Biophys J. 2010 Sep 8;99(5):1604-10. PMID:20816073 doi:10.1016/j.bpj.2010.06.026
