5NUN

Engineered beta-lactoglobulin: variant F105L-L39A-M107F in complex with chlorpromazine (LG-LAF-CLP)

Summary for 5NUN

• Entry DOI: 10.2210/pdb5nun/pdb
• Descriptor: Beta-lactoglobulin, 3-(2-chloro-10H-phenothiazin-10-yl)-N,N-dimethylpropan-1-amine (3 entities in total)
• Functional Keywords: beta-lactoglobulin, lipocalin, complex, mutation, transport protein
• Biological source: Bos taurus (Bovine)
• Cellular location: Secreted: P02754
• Total number of polymer chains: 1
• Total formula weight: 18491.76

Authors

Loch, J.I.,Bonarek, P.,Towrzydlo, M.,Lazinskia, I.,Szydlowska, J.,Lewinski, K. (deposition date: 2017-04-30, release date: 2018-04-04, Last modification date: 2024-11-20)

Primary citation

Loch, J.I.,Bonarek, P.,Tworzydlo, M.,Lazinska, I.,Szydlowska, J.,Lipowska, J.,Rzesikowska, K.,Lewinski, K.
The engineered beta-lactoglobulin with complementarity to the chlorpromazine chiral conformers.
Int. J. Biol. Macromol., 114:85-96, 2018

PubMed Abstract: Chlorpromazine (CPZ) is a phenothiazine acting as dopamine antagonist. Aside from application in schizophrenia therapy, chlorpromazine is found to be a putative inhibitor of proteins involved in cancers, heritable autism disorder and prion diseases. Four new β-lactoglobulin variants with double or triple substitutions: I56F/L39A, F105L/L39A, I56F/L39A/M107F or F105L/L39A/M107F changing the shape of the binding pocket were produced and their chlorpromazine binding properties have been investigated by X-ray crystallography, circular dichroism, isothermal titration calorimetry and thermophoresis. The CD spectra and crystal structures revealed that mutations do not affect the protein overall structure but in comparison to WT protein, variants possessing I56F substitution had lower stability while mutation F105L increased melting temperature of the protein. The new variants showed affinity to chlorpromazine in the range 4.2-15.4 × 10 M. The CD spectra and crystal structures revealed complementarity of the binding pocket shape, to only one chlorpromazine chiral conformer. The (aR)-CPZ was bonded to variants containing I56F substitution while variants with F105L substitution preferred (aS)-CPZ.

PubMed: 29555509
DOI: 10.1016/j.ijbiomac.2018.03.074

Experimental method

X-RAY DIFFRACTION (1.95 Å)