TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
*1.A.58.1.1









The Matrix protein BM2 (Pielak and Chou, 2010).  The solution structure for the channel domain of 33 aas is known (PDB# 2KIK) (Wang et al. 2009).  The channel transports H+ and K+ (Hyser and Estes 2015). Like M2, it is a tetrameric pore that acidifies the virion after endocytosis and it has a HxxxW motif (residues 19 - 23) in the single TMS responsible for proton selectivity and gating. This motif is within a 14 aa sequence with 35% identity and 86% similarity with M2 (1.A.19.1.1), both within the C-terminal part of the single TMS, suggesting homology. It also has a second histidine in a WxxxH motif involving the same W. The solvent-accessible His27 facilitates proton conduction of the channel by increasing the proton dissociation rates of His19 (Williams et al. 2017).

 

Viruses
Orthomyxoviridae
BM2 influenza virus type B
(P03493)
*1.A.58.1.2









Influenza Am2-Bm2 Chimeric Channel of 35 aas with 1 TMS. This hybrid sequence is RSNDSSDPLVVAASIIGILHFIAWTIGHLNQIKRG with the N-terminus derived from AM2 and the C-terminus derived from BM2 (PDB# 2KIK) (Pielak et al. 2011).
Viruses
Orthomyxoviridae
Chimeric AM2-BM2 35 aa peptide of A- and B-type Influenza viruses
*1.A.58.1.3









Influenza virus B Matrix Protein 2, BM2 protein, of 109 aas and 1 N-terminal TMS.  83% identical and 92% similar to 1.A.58.1.1.

Viruses
Orthomyxoviridae
BM2 of Influenza B virus (B/Maryland)