TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
1.B.96.1.1









OEP40 porin of 358 aas and 10 transmembrane β-strands. The reconstituted recombinant OEP40 protein forms a high conductance β-barrel ion channel with subconductant states in planar lipid bilayers. It is slightly cation-selective PK+/PCl- ≈ 4:1 and rectifying (i⃗/i⃖ ≅ 2) with a slope conductance of Ḡmax ≅ 690 picosiemens. It has a restriction zone diameter of ≅ 1.4 nm and is permeable to glucose, glucose 1-phosphate and glucose 6-phosphate, but not for maltose. Moreover, channel properties are regulated by trehalose 6-phosphate, which cannot permeate. Thus, OEP40 is a "glucose-gate" in the outer envelope membrane of chloroplasts, facilitating selective metabolite exchange between chloroplasts and the surrounding cytoplasm of the cell (Harsman et al. 2016).These porins and many others in eukaryotes have been reviewed and analyzed by Roumia et al. 2020.

Eukaryota
Viridiplantae, Streptophyta
OEP40 of Arabidopsis thaliana (Mouse-ear cress)
1.B.96.1.2









Uncharacterized OEP40 homologue of 304 aas and 10 putative β-strands

Eukaryota
Viridiplantae, Streptophyta
OEP40 homolog of Nyssa sinensis
1.B.96.1.3









Uncharacterized protein of 506 aas

Eukaryota
Viridiplantae, Streptophyta
UP of Marchantia paleacea
1.B.96.1.4









Uncharacterized putative beta-barrel protein of 528 aas and 1 N-terminal TMS

Eukaryota
Viridiplantae, Streptophyta
UP of Physcomitrium patens
1.B.96.1.5









Uncharacterized protein of 426 aas and possibly one N-terminal TMS

Eukaryota
Viridiplantae, Streptophyta
UP of Klebsormidium nitens
1.B.96.1.6









Uncharacterized protein of 487 aas, possibly with an N-terminal TMS, annotated in the NCBI database as cyclic nucleotide-gated ion channel 2.  However, the first 350 aas are homologous to OEP40 family members while the C-terminal residues (residues 400 - 480) are homologous to the cyclic nucleotide-gated ion channel, TMSs 2 - 31/2, of TC# 1.A.1.5.6.

Eukaryota
Viridiplantae, Streptophyta
UP of Zea mays