Crystal structure of human serum albumin at 2.5 A resolution.Sugio, S., Kashima, A., Mochizuki, S., Noda, M., Kobayashi, K.
(1999) Protein Eng 12: 439-446
- PubMed: 10388840
- DOI: https://doi.org/10.1093/protein/12.6.439
- Primary Citation of Related Structures:
- PubMed Abstract:
A new triclinic crystal form of human serum albumin (HSA), derived either from pool plasma (pHSA) or from a Pichia pastoris expression system (rHSA), was obtained from polyethylene glycol 4000 solution. Three-dimensional structures of pHSA and rHSA were determined at 2.5 A resolution from the new triclinic crystal form by molecular replacement, using atomic coordinates derived from a multiple isomorphous replacement work with a known tetragonal crystal form. The structures of pHSA and rHSA are virtually identical, with an r.m. s. deviation of 0.24 A for all Calpha atoms. The two HSA molecules involved in the asymmetric unit are related by a strict local twofold symmetry such that the Calpha atoms of the two molecules can be superimposed with an r.m.s. deviation of 0.28 A in pHSA. Cys34 is the only cysteine with a free sulfhydryl group which does not participate in a disulfide linkage with any external ligand. Domains II and III both have a pocket formed mostly of hydrophobic and positively charged residues and in which a very wide range of compounds may be accommodated. Three tentative binding sites for long-chain fatty acids, each with different surroundings, are located at the surface of each domain.
Osaka Laboratories, Yoshitomi Pharmaceutical Industries Ltd,2-25-1, Shodai-Ohtani, Hirakata, Osaka 573-1153, Japan.