Protein Family Models

This family includes proteins annotated as TonB dependent receptors. But it is also likely to contain other membrane beta barrel proteins of other functions. (from Pfam)

Date:

2024-08-14

The Plug domain has been shown to be an independently folding subunit of the TonB-dependent receptors ([1]). It acts as the channel gate, blocking the pore until the channel is bound by ligand. At this point it under goes conformational changes opens the channel. [1]. 15111112. The plug domain of a neisserial TonB-dependent transporter retains structural integrity in the absence of its transmembrane beta-barrel. Oke M, Sarra R, Ghirlando R, Farnaud S, Gorringe AR, Evans RW, Buchanan SK;. FEBS Lett 2004;564:294-300. (from Pfam)

Date:

2024-10-16

This entry represents the beta-barrel domain of TonB-dependent receptors, such as BtuB, CirA, FatA, FcuT, FecA, FepA, among others [1]. [1]. 9886293. Crystal structure of the outer membrane active transporter FepA from Escherichia coli. Buchanan SK, Smith BS, Venkatramani L, Xia D, Esser L, Palnitkar M, Chakraborty R, van der Helm D, Deisenhofer J;. Nat Struct Biol 1999;6:56-63. (from Pfam)

Date:

2024-10-16

This model represents a family of TonB-dependent outer-membrane receptors which are found mainly in Xanthomonas and Caulobacter. These appear to represent the expansion of a paralogous family in that the 22 X. axonopodis (21 in X. campestris) and 18 C. crescentus sequences are more closely related to each other than any of the many TonB-dependent receptors found in other species. In fact, the Crescentus and Xanthomonas sequences are inseparable on a phylogenetic tree using a PAM-weighted neighbor-joining method, indicating that one of the two genuses may have acquired this set of receptors from the other. The mechanism by which this family is shared between Xanthomonas, a gamma proteobacterial plant pathogen and Caulobacter, an alpha proteobacterial aquatic organism is unclear.

Date:

2021-04-27