Protein Family Models

HlyD_D23 is the combined domains 2 and 3 of the membrane-fusion proteins CusB and HlyD, which forms a barrel-sandwich. CusB and HlyD proteins are membrane fusion proteins of the CusCFBA copper efflux system in E.coli and related bacteria. The whole molecule hinges between D2 and D3. Efflux systems of this resistance-nodulation-division group - RND - have been developed to excrete poisonous metal ions, and in E.coli the only one that deals with silver and copper is the CusA transporter. The transporter CusA works in conjunction with a periplasmic component that is a membrane fusion protein, eg CusB, and an outer-membrane channel component CusC in a CusABC complex driven by import of protons. [1]. 19695261. Crystal structure of the membrane fusion protein CusB from Escherichia coli. Su CC, Yang F, Long F, Reyon D, Routh MD, Kuo DW, Mokhtari AK, Van Ornam JD, Rabe KL, Hoy JA, Lee YJ, Rajashankar KR, Yu EW;. J Mol Biol. 2009;393:342-355. (from Pfam)

Date:

2024-10-16

This is a family of largely bacterial haemolysin translocator HlyD proteins. (from Pfam)

Date:

2024-08-14

Date:

2024-08-14

The cation efflux system protein CusB from E. coli can be divided into four different domains, the first three domains of the protein are mostly beta-strands and the fourth forms an all alpha-helical domain. This entry represents the first beta-domain (domain 1) of CusB and it is formed by the N and C-terminal ends of the polypeptide (residues 89-102 and 324-385) [1]. CusB is part of the copper-transporting efflux system CusCFBA [2]. This domain can also be found in other membrane-fusion proteins, such as HlyD, MdtN, MdtE and AaeA. HlyD is a component of the prototypical alpha-haemolysin (HlyA) bacterial type I secretion system, along with the other components HlyB and TolC. HlyD is anchored in the cytoplasmic membrane by a single transmembrane domain and has a large periplasmic domain within the carboxy-terminal 100 amino acids [3], HlyB and HlyD form a stable complex that binds the recombinant protein bearing a C-terminal HlyA signal sequence and ATP in the cytoplasm [4]. HlyD, HlyB and TolC combine to form the three-component ABC transporter complex that forms a trans-membrane channel or pore through which HlyA can be transferred directly to the extracellular medium. Cutinase has been shown to be transported effectively through this pore [5]. [1]. 19695261. Crystal structure of the membrane fusion protein CusB from Escherichia coli. Su CC, Yang F, Long F, Reyon D, Routh MD, Kuo DW, Mokhtari AK, Van Ornam JD, Rabe KL, Hoy JA, Lee YJ, Rajashankar KR, Yu EW;. J Mol Biol. 2009;393:342-355. [2]. 12813074. Molecular analysis of the copper-transporting efflux system CusCFBA of Escherichia coli. Franke S, Grass G, Rensing C, Ni. TRUNCATED at 1650 bytes (from Pfam)

Date:

2024-10-16

This HMM represents the MFP (membrane fusion protein) component of the RND family of transporters. RND refers to Resistance, Nodulation, and cell Division. It is, in part, a subfamily of PF00529 (Pfam release 7.5) but hits substantial numbers of proteins missed by that HMM. The related HlyD secretion protein, for which PF00529 is named, is outside the scope of this model. Attributed functions imply outward transport. These functions include nodulation, acriflavin resistance, heavy metal efflux, and multidrug resistance proteins. Most members of this family are found in Gram-negative bacteria. The proposed function of MFP proteins is to bring the inner and outer membranes together and enable transport to the outside of the outer membrane. Note, however, that a few members of this family are found in Gram-positive bacteria, where there is no outer membrane.

Date:

2024-06-14