Structural highlights
3tuj is a 4 chain structure with sequence from Ecoli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| NonStd Res: | |
| Related: | |
| Gene: | b0198, JW0194, metI, yaeE (ECOLI), abc, b0199, JW0195, metN (ECOLI) |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[METI_ECOLI] Part of the binding-protein-dependent transport system for D-methionine and the toxic methionine analog alpha-methyl-methionine. Probably responsible for the translocation of the substrate across the membrane. [METN_ECOLI] Part of the ABC transporter complex MetNIQ involved in methionine import. Responsible for energy coupling to the transport system (Probable). It has also been shown to be involved in formyl-L-methionine transport.[1] [2]
Publication Abstract from PubMed
Two new crystal structures of the E. coli high affinity methionine uptake ATP Binding Cassette (ABC) transporter MetNI, purified in the detergents cyclohexyl-pentyl-beta-D-maltoside (CY5) and n-decyl-beta-D-maltopyranoside (DM), have been solved in inward facing conformations to resolutions of 2.9 and 4.0 A, respectively. Compared to the previously reported 3.7 A resolution structure of MetNI purified in n-dodecyl-beta-D-maltopyranoside (DDM), the higher resolution of the CY5 data enabled significant improvements to the structural model in several regions, including corrections to the sequence registry, and identification of ADP in the nucleotide binding site. CY5 crystals soaked with selenomethionine established details of the methionine binding site in the C2 regulatory domain of the ABC subunit, including the displacement of the side chain of MetN residue methionine 301 by the exogenous ligand. When compared to the CY5 or DDM structures, the DM structure exhibits a significant repositioning of the dimeric C2 domains, including an unexpected register shift in the intermolecular beta-sheet hydrogen bonding between monomers, and a narrowing of the nucleotide binding space. The immediate proximity of the exogenous methionine binding site to the conformationally variable dimeric interface provides an indication of how methionine binding to the regulatory domains might mediate the phenomenon of transinhibition.
Inward facing conformations of the MetNI methionine ABC transporter: Implications for the mechanism of transinhibition.,Johnson E, Nguyen PT, Yeates TO, Rees DC Protein Sci. 2011 Nov 16. doi: 10.1002/pro.765. PMID:22095702[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Gal J, Szvetnik A, Schnell R, Kalman M. The metD D-methionine transporter locus of Escherichia coli is an ABC transporter gene cluster. J Bacteriol. 2002 Sep;184(17):4930-2. PMID:12169620
- ↑ Zhang Z, Feige JN, Chang AB, Anderson IJ, Brodianski VM, Vitreschak AG, Gelfand MS, Saier MH Jr. A transporter of Escherichia coli specific for L- and D-methionine is the prototype for a new family within the ABC superfamily. Arch Microbiol. 2003 Aug;180(2):88-100. Epub 2003 Jun 19. PMID:12819857 doi:http://dx.doi.org/10.1007/s00203-003-0561-4
- ↑ Johnson E, Nguyen PT, Yeates TO, Rees DC. Inward facing conformations of the MetNI methionine ABC transporter: Implications for the mechanism of transinhibition. Protein Sci. 2011 Nov 16. doi: 10.1002/pro.765. PMID:22095702 doi:10.1002/pro.765
