Electrostatic Contributions to Protein Quinary Structure

被引:73
作者
Cohen, Rachel D. [1 ]
Pielak, Gary J. [1 ]
机构
[1] Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA
基金
美国国家科学基金会;
关键词
NUCLEAR-MAGNETIC-RESONANCE; IMMUNOGLOBULIN-BINDING DOMAIN; CHARGE-CHARGE INTERACTIONS; IN-CELL NMR; ESCHERICHIA-COLI; HYDROGEN-EXCHANGE; EXCLUDED-VOLUME; STABILITY; B1; SPECTROSCOPY;
D O I
10.1021/jacs.6b07323
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
There are four well-known levels of protein structure: primary (amino acid sequence), secondary (helices, sheets and turns), tertiary (three-dimensional structure) and quaternary (specific protein protein interactions). The fifth level remains largely undefined because characterization of quinary structure, the transient but essential macromolecular interactions that organize the crowded cellular interior, requires the measurement of equilibrium thermodynamic parameters in living cells. We have overcome this challenge by quantifying the pH dependence of quinary interactions in living Escherichia coli cells using the B1 domain of protein G (GB1, 6.2 kDa). To accomplish this goal, we buffered the cellular interior and used NMR-detected amide proton exchange to quantify the free energy of unfolding in cells. At neutral pH, the unfolding free energy in cells is comparable to that in buffered solution. As the pH decreases, the increased number of attractive interactions between E. coli proteins and GB1 destabilizes the protein in cells relative to buffer alone. The data show that electrostatic interactions contribute to quinary structure.
引用
收藏
页码:13139 / 13142
页数:4
相关论文
共 49 条
[1]   THERMODYNAMIC ANALYSIS OF THE FOLDING OF THE STREPTOCOCCAL PROTEIN-G IGG-BINDING DOMAINS B1 AND B2 - WHY SMALL PROTEINS TEND TO HAVE HIGH DENATURATION TEMPERATURES [J].
ALEXANDER, P ;
FAHNESTOCK, S ;
LEE, T ;
ORBAN, J ;
BRYAN, P .
BIOCHEMISTRY, 1992, 31 (14) :3597-3603
[2]   KINETIC-ANALYSIS OF FOLDING AND UNFOLDING THE 56-AMINO ACID IGG-BINDING DOMAIN OF STREPTOCOCCAL PROTEIN-G [J].
ALEXANDER, P ;
ORBAN, J ;
BRYAN, P .
BIOCHEMISTRY, 1992, 31 (32) :7243-7248
[3]   PRIMARY STRUCTURE EFFECTS ON PEPTIDE GROUP HYDROGEN-EXCHANGE [J].
BAI, YW ;
MILNE, JS ;
MAYNE, L ;
ENGLANDER, SW .
PROTEINS-STRUCTURE FUNCTION AND GENETICS, 1993, 17 (01) :75-86
[4]   Protein interaction patterns in different cellular environments are revealed by in-cell NMR [J].
Barbieri, Letizia ;
Luchinat, Enrico ;
Banci, Lucia .
SCIENTIFIC REPORTS, 2015, 5
[5]   PROTEIN STABILITY CURVES [J].
BECKTEL, WJ ;
SCHELLMAN, JA .
BIOPOLYMERS, 1987, 26 (11) :1859-1877
[6]   Unexpected Effects of Macromolecular Crowding on Protein Stability [J].
Benton, Laura A. ;
Smith, Austin E. ;
Young, Gregory B. ;
Pielak, Gary J. .
BIOCHEMISTRY, 2012, 51 (49) :9773-9775
[7]   Intracellular pH modulates quinary structure [J].
Cohen, Rachel D. ;
Guseman, Alex J. ;
Pielak, Gary J. .
PROTEIN SCIENCE, 2015, 24 (11) :1748-1755
[8]   Protein Interactions in the Escherichia coli Cytosol: An Impediment to In-Cell NMR Spectroscopy [J].
Crowley, Peter B. ;
Chow, Elysian ;
Papkovskaia, Tatiana .
CHEMBIOCHEM, 2011, 12 (07) :1043-1048
[9]   THE CONTROL AND CONSEQUENCES OF BACTERIAL FERMENTATION IN THE HUMAN COLON [J].
CUMMINGS, JH ;
MACFARLANE, GT .
JOURNAL OF APPLIED BACTERIOLOGY, 1991, 70 (06) :443-459
[10]   Thermodynamics of protein destabilization in live cells [J].
Danielsson, Jens ;
Mu, Xin ;
Lang, Lisa ;
Wang, Huabing ;
Binolfi, Andres ;
Theillet, Franois-Xavier ;
Bekei, Beata ;
Logan, Derek T. ;
Selenko, Philipp ;
Wennerstrom, Hakan ;
Oliveberg, Mikael .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2015, 112 (40) :12402-12407