Elastin-like polypeptide switches: A design strategy to detect multimeric proteins.
Protein Sci
; 26(9): 1785-1795, 2017 Sep.
Article
em En
| MEDLINE
| ID: mdl-28639381
ABSTRACT
Elastin-Like Polypeptides (ELPs) reversibly phase separate in response to changes in temperature, pressure, concentration, pH, and ionic species. While powerful triggers, biological microenvironments present a multitude of more specific biological cues, such as antibodies, cytokines, and cell-surface receptors. To develop better biosensors and bioresponsive drug carriers, rational strategies are required to sense and respond to these target proteins. We recently reported that noncovalent association of two ELP fusion proteins to a "chemical inducer of dimerization" small molecule (1.5 kDa) induces phase separation at physiological temperatures. Having detected a small molecule, here we present the first evidence that ELP multimerization can also detect a much larger (60 kDa) protein target. To demonstrate this strategy, ELPs were biotinylated at their amino terminus and mixed with tetrameric streptavidin. At a stoichiometric ratio of [41], two to three biotin-ELPs associate with streptavidin into multimeric complexes with an apparent Kd of 5 nM. The increased ELP density around a streptavidin core strongly promotes isothermal phase separation, which was tuned to occur at physiological temperature. This phase separation reverses upon saturation with excess streptavidin, which only favors [11] complexes. Together, these findings suggest that ELP association with multimeric biomolecules is a viable strategy to deliberately engineer ELPs that respond to multimeric protein substrates.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Peptídeos
/
Elastina
/
Multimerização Proteica
Idioma:
En
Revista:
Protein Sci
Assunto da revista:
BIOQUIMICA
Ano de publicação:
2017
Tipo de documento:
Article