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Structural conservation in the major facilitator superfamily as revealed by comparative modeling.

ABSTRACT: The structures of membrane transporters are still mostly unsolved. Only recently, the first two high-resolution structures of transporters of the major facilitator superfamily (MFS) were published. Despite the low sequence similarity of the two proteins involved, lactose permease and glycerol-3-phosphate transporter, the reported structures are highly similar. This leads to the hypothesis that all members of the MFS share a similar structure, regardless of their low sequence identity. To test this hypothesis, we generated models of two other members of the MFS, the Tn10-encoded metal-tetracycline/H(+) antiporter (TetAB) and the rat vesicular monoamine transporter (rVMAT2). The models are based on the two MFS structures and on experimental data. The models for both proteins are in good agreement with the data available and support the notion of a shared fold for all MFS proteins.

SUBMITTER: Vardy E

PROVIDER: S-EPMC2279927 | biostudies-literature | 2004 Jul

REPOSITORIES: biostudies-literature

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Structural conservation in the major facilitator superfamily as revealed by comparative modeling.

Vardy Eyal E Arkin Isaiah T IT Gottschalk Kay E KE Kaback H Ronald HR Schuldiner Shimon S

Protein science : a publication of the Protein Society 20040701 7

The structures of membrane transporters are still mostly unsolved. Only recently, the first two high-resolution structures of transporters of the major facilitator superfamily (MFS) were published. Despite the low sequence similarity of the two proteins involved, lactose permease and glycerol-3-phosphate transporter, the reported structures are highly similar. This leads to the hypothesis that all members of the MFS share a similar structure, regardless of their low sequence identity. To test th ...[more]

PMID: 15215526

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Comparative stability of Major Facilitator Superfamily transport proteins.

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Structure and mechanism of a redesigned multidrug transporter from the Major Facilitator Superfamily.

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