| UniProt functional annotation for O27564 | |||
| UniProt code: O27564. |
| Organism: | Methanothermobacter thermautotrophicus (strain ATCC 29096 / DSM 1053 / JCM 10044 / NBRC 100330 / Delta H) (Methanobacterium thermoautotrophicum). | |
| Taxonomy: | Archaea; Euryarchaeota; Methanomada group; Methanobacteria; Methanobacteriales; Methanobacteriaceae; Methanothermobacter. | |
| Function: | Calcium-gated potassium channel. | |
| Subunit: | Homotetramer. | |
| Subcellular location: | Cell membrane; Multi-pass membrane protein. | |
| Domain: | The channel is composed of 4 repeated units, each containing a transmembrane pore part and a gating ring part. The gating ring is composed of eight identical RCK (Regulators of K conductance) domains, in an alternating arrangement of one domain from each of the four subunits and four from the intracellular solution. Two protein interfaces between dimers of RCK domains from the pore-forming subunit and from the intracellular solution hold the ring together. One is called the fixed interface and the other the flexible interface. The flexible interface forms a cleft where calcium binds. Upon calcium binding the gating ring undergoes a conformational change that enables it to pull open the inner helices of the pore, allowing ion conduction. | |
| Miscellaneous: | It is not known whether calcium is the physiological ligand. | |
| Miscellaneous: | Inhibited by charybdotoxin (CTX), a protein from scorpion venom. | |
Annotations taken from UniProtKB at the EBI.