Kalata B7

Kalata B7 is a cyclotide that can be isolated from Oldenlandia affinis DC (Rubiaceae) and possesses membrane-permeating capabilities. Kalata B7 is also a partial agonist of oxytocin and vasopressin V1a receptors[1][2].

O=C(N1[C@@](C(N[C@@](C(N[C@]2([H])C(N[C@H](C(N[C@H](C(N[C@H](C(NCC(N[C@H](C(N3[C@](CCC3)([H])C(N[C@H](C(N[C@@]4([H])CSSC[C@@]5([H])C(N[C@@](C(N[C@](CSSC[C@@](NC([C@](NC([C@@H](NC(CNC4=O)=O)CCC(O)=O)=O)([H])[C@H](O)C)=O)([H])C(N[C@@](C(N[C@H](C(NCC(N[C@@](C(N[C@@](C(N[C@H](C(N[C@@](C(N[C@H](C(NCC(N5)=O)=O)CCC(N)=O)=O)([H])[C@H](O)C)=O)CC6=CC=C(C=C6)O)=O)([H])CSSC2)=O)([H])[C@H](O)C)=O)=O)CC(C)C)=O)([H])[C@H](O)C)=O)([H])C(N[C@H](C(N7)=O)CO)=O)=O)([H])[C@H](O)C)=O)=O)C(C)C)=O)=O)CC(C)C)=O)=O)CC(N)=O)=O)CCCNC(N)=N)=O)CCCCN)=O)=O)([H])[C@@H](C)CC)=O)([H])CCC1)[C@@H]7CC8=CNC9=CC=CC=C89

[1]Strömstedt AA, et al. Selective membrane disruption by the cyclotide kalata B7: complex ions and essential functional groups in the phosphatidylethanolamine binding pocket. Biochim Biophys Acta. 2016;1858(6):1317-1327.|[2]Taghizadeh MS, et al. Discovery of the cyclotide caripe 11 as a ligand of the cholecystokinin-2 receptor. Sci Rep. 2022 Jun 2;12(1):9215.