Factors that influence competitive intermolecular solvation of protonated groups in peptides and proteins in the gas phase.

ABSTRACT: The ability of 18-crown-6 (18C6) to form noncovalent complexes with cationic groups in the gas phase has been leveraged in numerous, largely orthogonal mass spectrometry-based applications. Although the fundamental interaction between 18C6 and a charged group in the gas phase is quite strong, the strength of attachment of 18C6 to large molecules is more difficult to predict because intramolecular binding of the cation can be competitive. Herein, we demonstrate in experiments with model peptides that 18C6 adducts are not strongly attached to flexible molecules with numerous potential hydrogen bonding sites. 18C6 adduct stability is increased if intramolecular charge complexation is inhibited by sterics or competitive binding. It is demonstrated with molecular mechanics that significant stru

SUBMITTER: Tao Y 

PROVIDER: S-EPMC3806280 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature