Engineering covalent oligomers of the mechanosensitive channel of large conductance from Escherichia coli with native conductance and gating characteristics.
To obtain a gene construct for making single substitutions per channel and to determine the quaternary structure of the mechanosensitive channel MscL from Escherichia coli, covalent oligomers (monomer to hexamer) were engineered by gene fusion; up to six copies of the mscL gene were fused in tandem. All the multimeric tandem constructs yielded functional channels with wild-type conductance and dwell times. Importantly, only the covalent pentamer opened at the same relative pressure (compared to the pressure required to open MscS) as the wild-type MscL channel. The in vivo data strongly suggest that pentameric MscL represents the functional state of the channel.
Folgering
Joost H A
JH
Department of Biochemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
Wolters
Justina C
JC
Poolman
Bert
B
D000595:Amino Acid Sequence; D001483:Base Sequence; D004553:Electric Conductivity; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D015640:Ion Channel Gating; D007473:Ion Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D015202:Protein Engineering; D020836:Protein Structure, Quaternary
D029968:Escherichia coli Proteins; D007473:Ion Channels; C086596:MscL protein, E coli