Isolation and characterisation of porin from the outer membrane of Synechococcus PCC 6301.
Pore-forming protein (porin) was isolated from N,N-dimethyl-dodecylaminoxid (LDAO)-extracted outer membranes of Synechococcus PCC 6301 and purified by ion exchange chromatography on DEAE-Sephacel column. The apparent molecular mass on SDS-PAGE was determined to be about 52,000. The native porin was reconstituted into black lipid bilayer membranes and showed a single-channel conductance of 5.5 nS in 1 M KCl. The porin was found to be N-terminally blocked. The C-terminal amino acid sequence was identified as Phe-Thr-Phe. Amino acid analysis suggested that the porin protein consists of about 420 amino acid residues, yielding a polarity of 43.6% and a molecular mass of 45,000 in contrast to the mobility on SDS-PAGE.
Hansel
A
A
Institut für Biologie II, Mikrobiologie, Albert-Ludwigs-Universität, Freiburg, Germany.
Schmid
A
A
Tadros
M H
MH
Jürgens
U J
UJ
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D002462:Cell Membrane / Q000737:chemistry; D000458:Cyanobacteria / Q000737:chemistry* / Q000648:ultrastructure; D007473:Ion Channels / Q000032:analysis; D008051:Lipid Bilayers; D008969:Molecular Sequence Data; D008970:Molecular Weight; D018272:Porins / Q000032:analysis / Q000737:chemistry*; D017421:Sequence Analysis
D000596:Amino Acids; D007473:Ion Channels; D008051:Lipid Bilayers; D018272:Porins