Robuta

https://www.ncbi.nlm.nih.gov/Structure/pdb/5L8G
Uncharacterized proteinCALCIUM ION
crystal structurerhodospirillum rubrumrrumutant
https://www.ncbi.nlm.nih.gov/Structure/pdb/3HEB
Response regulator receiver domain protein (CheY)PHOSPHATE ION
crystal structureresponse regulatorreceiverdomain