What are the structural features that drive partitioning of proteins in aqueous two-phase systems?
Protein partitioning in aqueous two-phase systems (ATPSs) represents a convenient, inexpensive, and easy to scale-up protein separation technique. Since partition behavior of a protein dramatically depends on an ATPS composition, it would be highly beneficial to have reliable means for (even qualitative) prediction of partitioning of a target protein under different conditions. Our aim was to understand which structural features of proteins contribute to partitioning of a query protein in a given ATPS. We undertook a systematic empirical analysis of relations between 57 numerical structural descriptors derived from the corresponding amino acid sequences and crystal structures of 10 well-characterized proteins and the partition behavior of these proteins in 29 different ATPSs. This analysis revealed that just a few structural characteristics of proteins can accurately determine behavior of these proteins in a given ATPS. However, partition behavior of proteins in different ATPSs relies on different structural features. In other words, we could not find a unique set of protein structural features derived from their crystal structures that could be used for the description of the protein partition behavior of all proteins in all ATPSs analyzed in this study. We likely need to gain better insight into relationships between protein-solvent interactions and protein structure peculiarities, in particular given limitations of the used here crystal structures, to be able to construct a model that accurately predicts protein partition behavior across all ATPSs.
School of Mathematical Sciences and LPMC, Nankai University, Tianjin, People's Republic of China.
Zhonghua
Z
Wu
School of Mathematical Sciences and LPMC, Nankai University, Tianjin, People's Republic of China.
Gang
G
Hu
School of Mathematical Sciences and LPMC, Nankai University, Tianjin, People's Republic of China.
Kui
K
Wang
Cleveland Diagnostics, 3615 Superior Avenue, Suite 4407B, Cleveland, OH 44114, USA. Electronic address: boris.zaslavsky@cleveland-diagnostics.com.
Boris Yu
BY
Zaslavsky
Department of Computer Science, Virginia Commonwealth University, Richmond, VA, USA. Electronic address: lkurgan@vcu.edu.
Lukasz
L
Kurgan
Department of Molecular Medicine and Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; Laboratory of structural dynamics, stability and folding of proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia. Electronic address: vuversky@health.usf.edu.
Vladimir N
VN
Uversky
D005591:Chemical Fractionation; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry* / Q000302:isolation & purification*; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry
D011506:Proteins; D012997:Solvents; D014867:Water
Aqueous two phase system; Partition; Protein structural feature; Protein structure