Calcium in PDB 6qtn: Tubulin-Cyclostreptin Complex

The structure of Tubulin-Cyclostreptin Complex, PDB code: 6qtn was solved by F.D.A.Balaguer, T.Muehlethaler, J.Estevez-Gallego, E.Calvo, J.F.Gimenez-Abian, A.L.Risinger, E.J.Sorensen, C.D.Vanderwal, K.-H.Altmann, S.L.Mooberry, M.O.Steinmetz, M.A.Oliva, A.E.Prota, J.F.Diaz, with X-Ray Crystallography technique. A brief refinement statistics is given in the table below:

Resolution Low / High (Å)	49.66 / 1.90
Space group	P 21 21 21
Cell size a, b, c (Å), α, β, γ (°)	104.585, 158.361, 179.946, 90.00, 90.00, 90.00
R / Rfree (%)	18.7 / 21.3

The structure of Tubulin-Cyclostreptin Complex also contains other interesting chemical elements:

Magnesium

(Mg)

5 atoms

The binding sites of Calcium atom in the Tubulin-Cyclostreptin Complex (pdb code 6qtn). This binding sites where shown within 5.0 Angstroms radius around Calcium atom.
In total 2 binding sites of Calcium where determined in the Tubulin-Cyclostreptin Complex, PDB code: 6qtn:
Jump to Calcium binding site number: 1; 2;

Calcium binding site 1 out of 2 in the Tubulin-Cyclostreptin Complex


Mono view


Stereo pair view

A full contact list of Calcium with other atoms in the Ca binding site number 1 of Tubulin-Cyclostreptin Complex within 5.0Å range: probe atom residue distance (Å) B Occ A:Ca503 b:68.8 occ:1.00 O A:GLY44 2.2 77.5 1.0 O A:THR41 2.5 74.6 1.0 O A:HOH616 2.5 70.9 1.0 OG1 A:THR41 2.5 72.2 1.0 OD2 A:ASP39 2.5 78.6 1.0 OE2 A:GLU55 2.5 69.7 1.0 OD1 A:ASP39 2.6 79.6 1.0 OE1 A:GLU55 2.6 65.3 1.0 CG A:ASP39 2.9 78.1 1.0 CD A:GLU55 2.9 79.0 1.0 CB A:THR41 3.4 86.4 1.0 C A:GLY44 3.4 81.5 1.0 C A:THR41 3.5 85.5 1.0 CA A:THR41 3.8 87.8 1.0 CA A:GLY45 4.1 76.5 1.0 N A:GLY45 4.2 82.0 1.0 N A:THR41 4.2 79.7 1.0 N A:GLY44 4.3 85.0 1.0 CB A:ASP39 4.4 77.9 1.0 CG A:GLU55 4.4 76.4 1.0 CZ A:PHE49 4.4 74.4 1.0 CA A:GLY44 4.4 84.6 1.0 OD1 A:ASN50 4.5 67.9 1.0 OD2 A:ASP47 4.6 69.8 1.0 N A:ILE42 4.7 85.0 1.0 CE1 A:PHE49 4.7 70.3 1.0 CG2 A:THR41 4.7 76.9 1.0 NE2 A:HIS61 4.8 74.0 1.0 ND2 A:ASN50 4.9 64.9 1.0

Calcium binding site 2 out of 2 in the Tubulin-Cyclostreptin Complex


Mono view


Stereo pair view

A full contact list of Calcium with other atoms in the Ca binding site number 2 of Tubulin-Cyclostreptin Complex within 5.0Å range: probe atom residue distance (Å) B Occ C:Ca503 b:52.4 occ:1.00 OE1 C:GLU55 2.3 53.1 1.0 O C:THR41 2.3 50.4 1.0 O C:GLY44 2.4 64.5 1.0 O C:HOH636 2.4 42.5 1.0 OD2 C:ASP39 2.4 55.8 1.0 OE2 C:GLU55 2.4 51.8 1.0 OG1 C:THR41 2.5 63.8 1.0 OD1 C:ASP39 2.7 57.6 1.0 CD C:GLU55 2.7 50.7 1.0 CG C:ASP39 2.9 55.6 1.0 C C:THR41 3.4 65.4 1.0 C C:GLY44 3.5 73.9 1.0 CB C:THR41 3.6 66.7 1.0 CA C:THR41 3.9 66.1 1.0 N C:THR41 4.2 60.1 1.0 CG C:GLU55 4.2 51.2 1.0 N C:GLY44 4.3 74.1 1.0 N C:GLY45 4.3 73.3 1.0 CA C:GLY45 4.3 64.9 1.0 CB C:ASP39 4.4 53.1 1.0 CA C:GLY44 4.4 74.3 1.0 O C:HOH664 4.4 51.2 1.0 N C:ILE42 4.5 61.3 1.0 OD1 C:ASN50 4.5 51.5 1.0 OD2 C:ASP47 4.6 58.6 1.0 NE2 C:HIS61 4.6 47.2 1.0 CZ C:PHE49 4.8 51.3 1.0 ND2 C:ASN50 4.8 47.7 1.0 CG2 C:THR41 4.9 55.9 1.0 CE1 C:PHE49 4.9 46.5 1.0 CA C:ILE42 4.9 65.4 1.0

F.A.Balaguer, T.Muhlethaler, J.Estevez-Gallego, E.Calvo, J.F.Gimenez-Abian, A.L.Risinger, E.J.Sorensen, C.D.Vanderwal, K.H.Altmann, S.L.Mooberry, M.O.Steinmetz, M.A.Oliva, A.E.Prota, J.F.Diaz. Crystal Structure of the Cyclostreptin-Tubulin Adduct: Implications For Tubulin Activation By Taxane-Site Ligands. Int J Mol Sci V. 20 2019.
ISSN: ESSN 1422-0067
PubMed: 30897704
DOI: 10.3390/IJMS20061392