Remodeling of phosphatidylglycerol in Synechocystis PCC6803.
The phosphatidylglycerol deficient DeltapgsA mutant of Synechocystis PCC6803 provided a unique experimental system for investigating in vivo retailoring of exogenously added dioleoylphosphatidylglycerol in phosphatidylglycerol-depleted cells. Gas chromatographic analysis of fatty acid composition suggested that diacyl-phosphatidylglycerols were synthesized from the artificial synthetic precursor. The formation of new, retailored lipid species was confirmed by negative-ion electrospray ionization-Fourier-transform ion cyclotron resonance and ion trap tandem mass spectrometry. Various isomeric diacyl-phosphatidylglycerols were identified indicating transesterification of the exogenously added dioleoylphosphatidyl-glycerol at the sn-1 or sn-2 positions. Polyunsaturated fatty acids were incorporated selectively into the sn-1 position. Our experiments with Synechocystis PCC6803/DeltapgsA mutant cells demonstrated lipid remodeling in a prokaryotic photosynthetic bacterium. Our data suggest that the remodeling of diacylphosphatidylglycerol likely involves reactions catalyzed by phospholipase A(1) and A(2) or acyl-hydrolase, lysophosphatidylglycerol acyltransferase and acyl-lipid desaturases.
Institute of Plant Biology, Biological Research Center, Hungarian Academy of Sciences, H-6701 Szeged, P.O. Box 521, Hungary.
Hajnalka
H
Laczko-Dobos
Petr
P
Frycák
Bettina
B
Ughy
Ildiko
I
Domonkos
Hajime
H
Wada
Laszlo
L
Prokai
Zoltan
Z
Gombos
D000217:Acyltransferases / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D008246:Lysophospholipids / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D010715:Phosphatidylglycerols / Q000737:chemistry* / Q000378:metabolism*; D054466:Phospholipases A1 / Q000378:metabolism; D054467:Phospholipases A2 / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D017550:Spectroscopy, Fourier Transform Infrared; D046939:Synechocystis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
D005231:Fatty Acids, Unsaturated; D008246:Lysophospholipids; D010715:Phosphatidylglycerols; C026223:lysophosphatidylglycerol; D000217:Acyltransferases; D054466:Phospholipases A1; D054467:Phospholipases A2