Structural and functional characterization of a synthetically modified OmpG.
Chemical modification of ion channels has recently attracted attention due to their potential use in stochastic sensing and neurobiology. Among the available channel templates stable β-barrel proteins have shown their potential for large scale chemical modifications due to their wide pore lumen. Ion-channel hybrids using the outer membrane protein OmpG were generated by S-alkylation with a synthetic modulator and functionally as well as structurally characterized. The dansyl moiety of the used modulator resulted in partial blockage of current though the OmpG channel with its gating characteristics mainly unaffected. The crystal structure of an OmpG-dansyl hybrid at 2.4Å resolution correlates this finding by showing that the modulator lines the inner walling of the OmpG pore. These results underline the suitability of OmpG as a structural base for the construction of stochastic sensors.
Grosse
Wolfgang
W
Philipps-Universität Marburg, Fachbereich Chemie, Hans-Meerwein-Straße, 35032 Marburg, Germany.
Reiss
Philipp
P
Reitz
Simon
S
Cebi
Menekse
M
Lübben
Wolger
W
Koert
Ulrich
U
Essen
Lars-Oliver
LO
D000478:Alkylation; D019943:Amino Acid Substitution; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018360:Crystallography, X-Ray; D003619:Dansyl Compounds / Q000737:chemistry; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D018272:Porins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary
D001425:Bacterial Outer Membrane Proteins; D003619:Dansyl Compounds; D029968:Escherichia coli Proteins; C114347:OmpG protein, E coli; D018272:Porins; C029038:dansyl chloride