[65] Phosphatidylglycerophosphate synthase from Escherichia coli

Dowhan, William; Hirabayashi, Takashi

doi:10.1016/0076-6879(81)71067-x

Cited by 9 publications

(5 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…By using the MOTIF search program (2) to compare the PgsA Rs with the data library, a region was identified as containing the CDP-alcohol/ phosphatidyltransferase signature (29). When an alignment of seven CDP-diacylglycerol-dependent phospholipid biosynthetic enzymes from several sources (8,14,53) was performed, a region of homology which could be of importance in the function of these proteins was identified (Fig. 2B).…”

Section: Resultsmentioning

confidence: 99%

Isolation and expression of the Rhodobacter sphaeroides gene (pgsA) encoding phosphatidylglycerophosphate synthase

Dryden

Dowhan

1996

J Bacteriol

View full text Add to dashboard Cite

The Rhodobacter sphaeroides pgsA gene (pgsA Rs ), encoding phosphatidylglycerophosphate synthase (PgsA Rs ), was cloned, sequenced, and expressed in both R. sphaeroides and Escherichia coli. As in E. coli, pgsA Rs is located immediately downstream of the uvrC gene. Comparison of the deduced amino acid sequences revealed 41% identity and 69% similarity to the pgsA gene of E. coli, with similar homology to the products of the putative pgsA genes of several other bacteria. Comparison of the amino acid sequences of a number of enzymes involved in CDP-diacylglycerol-dependent phosphatidyltransfer identified a highly conserved region also found in PgsA Rs . The pgsA Rs gene carried on multicopy plasmids was expressed in R. sphaeroides under the direction of its own promoter, the R. sphaeroides rrnB promoter, and the E. coli lac promoter, and this resulted in significant overproduction of PgsA Rs activity. Expression of PgsA Rs activity in E. coli occurred only with the E. coli lac promoter. PgsA Rs could functionally replace the E. coli enzyme in both a point mutant and a null mutant of E. coli pgsA. Overexpression of PgsA Rs in either E. coli or R. sphaeroides did not have dramatic effects on the phospholipid composition of the cells, suggesting regulation of the activity of this enzyme in both organisms.Rhodobacter sphaeroides is a gram-negative bacterium capable of growth by aerobic and anaerobic respiration, fermentation, and anoxygenic photosynthesis (34). R. sphaeroides responds to changes in its environment with both physiological and morphological adaptations. Under aerobic conditions, the organism has a typical gram-negative outer membrane and cytoplasmic membrane. At low oxygen tension a dramatic differentiation of the cytoplasmic membrane occurs, with the formation of an intracytoplasmic membrane. The intracytoplasmic membrane is physically continuous with the cytoplasmic membrane but structurally and functionally distinct. The intracytoplasmic membrane contains all of the components necessary for photosynthesis (34). Studies on the regulation of intracytoplasmic membrane assembly have demonstrated the cell cycle-specific insertion of phospholipids into the intracytoplasmic membrane of photoheterotrophically growing cells (13,32), with protein and photopigments incorporated continuously into the intracytoplasmic membrane throughout the cell cycle. Insertion of phospholipids into the intracytoplasmic membrane is concurrent with the onset of cell division and is the result of the net transfer of phospholipids previously synthesized outside the intracytoplasmic membrane (13,32,51). Although the intracytoplasmic membrane and its protein components have been extensively studied, the role specific phospholipid species and general phospholipid metabolism play in the induction, synthesis, assembly, and function of the intracytoplasmic membrane has received only limited attention, mainly because of the lack of detailed biochemical information relating to phospholipid metabolism and lack of genetic information on the...

show abstract

Section: Resultsmentioning

confidence: 99%

Isolation and expression of the Rhodobacter sphaeroides gene (pgsA) encoding phosphatidylglycerophosphate synthase

Dryden

Dowhan

1996

J Bacteriol

View full text Add to dashboard Cite

show abstract

“…Pgs converts CDP-diacylglycerol to phosphatidylglycerophosphate, which leads to the synthesis of the two anionic phospholipids of this organism (Raetz and Dowhan, 1990). Similarly to most of the enzymes involved in membrane-lipid biosynthesis and regulation, this enzyme is tightly associated with the cytoplasmic membrane (Dowhan, 1992). The nucleotide sequence of the gene encoding Pgs @gsA) has been determined and predicts a gene product of 182 amino acid residues with a molecular mass of 20.7 kDa (Usui et al, 1994).…”

mentioning

confidence: 99%

Two‐Dimensional ¹H‐NMR of Transmembrane Peptides from Escherichia Coli Phosphatidylglycerophosphate Synthase in Micelles

Morein

Trouard

Hauksson

et al. 1996

European Journal of Biochemistry

View full text Add to dashboard Cite

Two 28-residue peptides, PTLLTLFRVILIPFFVLVFYKKKGKKKG [Pgs-(6-25)-peptidyl-KKKGKKKG; Pgs peptide A] and VEYAGIALFFVAAVLTLWSMLQYLSAAR )-peptide, Pgs peptide El, were synthesized and studied by CD and two-dimensional 'H-NMR spectroscopy. The first 20 amino acid residues of Pgs peptide A are identical to one predicted transmembrane segment (Pro6 -Tyr25) of the integral membrane protein phosphatidylglycerophosphate synthase (Pgs) of Escherichiu coli. Pgs peptide E is identical to another predicted transmembrane segment (Va1149-Arg176), which is located in the C-terminal end of this lipid synthase. Pgs peptides A and E were dissolved in methanol or trifluoroethanol or were incorporated into solvent-free micelles of fully deuterated SDS. In all these systems, CD spectra of both peptides indicated an a-helical secondary structure. However, peptides that were solubilized in micelles exhibited the highest content of a-helix as judged from comparison of the CD spectra. Thermodynamically stable isotropic solutions at high peptide concentrations (1 -3 mM) could only be obtained with the peptide incorporated in micelles; in organic solvents, significant peptide aggregation occurred. Relatively sharp peaks were obtained with 'H-NMR spectroscopy of the peptides in SDS micelles, which indicates rapid tumbling of the peptides in the micellar environment. Translational-diffusion coefficients of the micelles with and without peptide, determined by pulsed-fieldgradient NMR, showed that the micellar size was unaffected by the solubilized peptide. The radius of the hydrated micelles was estimated to be about 2.7 nm (i.e. the mass of the aggregate is almost 30 kDa). Two-dimensional NMR spectroscopy of both peptides solubilized in the micelles indicated an a-helical conformation. This observation is strengthened by an investigation of the hydrogen exchange of the peptide amide protons, where significantly less exchange of the amide protons was observed in the middle of the peptides compared with the ends.

show abstract

“…Prefractionation of the lipids prior to analysis by mass spectrometry uncovers ions arising from some of these minor lipids. For example, in this work, we were able to identify a series of ions corresponding to molecules of phosphatidylglycerol phosphate, the immediate precursor of PG ( 21,36,37 ) only after prefractionation of the total lipids using anion exchange chromatography ( Fig. 2 ).…”

Section: Discussionmentioning

confidence: 96%

Identification of phosphatidylserylglutamate: a novel minor lipid in Escherichia coli

Garrett

Raetz

Richardson

et al. 2009

Journal of Lipid Research

View full text Add to dashboard Cite

dylglycerol phosphate ( 3 ). For each of these lipids, there can exist several molecular species arising from the different lengths, unsaturation, and/or cyclopropane analogs of the acyl chains ( 4 ). The complexity of the E. coli lipidome, however, is even greater than can be explained by acyl chain heterogeneity. Numerous additional minor lipids are present in wild-type cells, as judged by isotopic labeling experiments and two-dimensional TLC ( 3 ). Many of these species cannot be identifi ed by their migration with standards of known lipids or biosynthetic precursors.Electrospray ionization-mass spectrometry (ESI-MS) is well suited to the analysis of intact lipids ( 5 ). Fragmentation during ionization is minimized and the sensitivity is high ( 6, 7 ). In addition, collision-induced dissociation mass spectrometry (MS/MS) allows for the structural analysis of the lipid ion of interest and, when combined with the high mass accuracy of time-of-fl ight mass spectrometers, can be used to propose a molecular formula for a particular ion.Current applications of mass spectrometry to lipid analysis have focused mainly on the quantifi cation of known lipid species, often coupling liquid chromatography directly to the mass spectrometer ( 8-10 ). These analyses compare levels of known lipid species present under various growth conditions or disease states. However, important changes in levels of unknown or minor lipids are diffi cult to analyze without knowledge of their structures and the availability of appropriate standards. Phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and cardiolipin (CL) are the major membrane glycerophospholipids of Escherichia coli , constituting about 10% of the dry weight of the cell ( 1, 2 ). Important minor lipids include the precursors phosphatidic acid, CDP-diacylglycerol, phosphatidylserine, and phosphati-

show abstract

[65] Phosphatidylglycerophosphate synthase from Escherichia coli

Cited by 9 publications

References 8 publications

Isolation and expression of the Rhodobacter sphaeroides gene (pgsA) encoding phosphatidylglycerophosphate synthase

Isolation and expression of the Rhodobacter sphaeroides gene (pgsA) encoding phosphatidylglycerophosphate synthase

Two‐Dimensional ¹H‐NMR of Transmembrane Peptides from Escherichia Coli Phosphatidylglycerophosphate Synthase in Micelles

Identification of phosphatidylserylglutamate: a novel minor lipid in Escherichia coli

Contact Info

Product

Resources

About

[65] Phosphatidylglycerophosphate synthase from Escherichia coli

Cited by 9 publications

References 8 publications

Isolation and expression of the Rhodobacter sphaeroides gene (pgsA) encoding phosphatidylglycerophosphate synthase

Isolation and expression of the Rhodobacter sphaeroides gene (pgsA) encoding phosphatidylglycerophosphate synthase

Two‐Dimensional 1H‐NMR of Transmembrane Peptides from Escherichia Coli Phosphatidylglycerophosphate Synthase in Micelles

Identification of phosphatidylserylglutamate: a novel minor lipid in Escherichia coli

Contact Info

Product

Resources

About

Two‐Dimensional ¹H‐NMR of Transmembrane Peptides from Escherichia Coli Phosphatidylglycerophosphate Synthase in Micelles