Characterization of two genes, glpQ and ugpQ, encoding glycerophosphoryl diester phosphodiesterases of Escherichia coli

Tommassen, Jan; Eiglmeier, Karin; Cole, Stewart T.; Overduin, Piet; Larson, Timothy J.; Boos, Winfried

doi:10.1007/bf00273621

Cited by 92 publications

(77 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The two E. coli GP-PDEs GlpQ and UgpQ play important roles in the uptake and metabolism of GPs as well as the degradation product G3P, which is a major carbon and phosphate source (21,24). In mammals, no GP-PDE has been cloned up to now.…”

Section: Discussionmentioning

confidence: 99%

“…A BLAST search with the amino acid sequence of MIR16 indicated that MIR16 has significant homology with GP-PDEs (EC 3.1.4.46) from E. coli (20,21) and Haemophilus influenzae (22), suggesting that MIR16 may have GP-PDE enzymatic activity. GP-PDE hydrolyzes deacylated phospholipid GPs, such as glycerophosphocholine (GPC) and glycerophosphoethanolamine, to snglycerol-3-phosphate (G3P) and the corresponding alcohols (22,23).…”

Section: ϫ21mentioning

confidence: 99%

See 1 more Smart Citation

MIR16, a putative membrane glycerophosphodiester phosphodiesterase, interacts with RGS16

Zheng

Chen

Farquhar

2000

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

We have identified the protein MIR16 (for Membrane Interacting protein of RGS16) from a yeast two-hybrid screen by using RGS16 as bait. MIR16 shares strong homology with bacterial glycerophosphodiester phosphodiesterases. It interacts with RGS16 and, more weakly, with several other selected RGS proteins. Analysis of deletion mutants showed that the N-terminal region of the RGS domain in RGS16 is required for its interaction with MIR16. MIR16 is an integral membrane glycoprotein, because it remained associated with membrane fractions after alkaline treatment and because, in some cells, it is sensitive to digestion with endoglycosidase H. By immunofluorescence and immunoelectron microscopy, MIR16 was localized on the plasma membrane in liver and kidney and on intracellular membranes in rat pituitary and cultured pituitary cells. MIR16 represents the only integral membrane protein identified thus far to interact with an RGS domain and, to our knowledge, is the only mammalian glycerophosphodiester phosphodiesterase that has been cloned. The putative enzymatic activity of MIR16 and its interaction with RGS16 suggest that it may play important roles in lipid metabolism and in G protein signaling.G protein ͉ integral membrane protein ͉ lipid metabolism H eterotrimeric G proteins transduce a variety of extracellular signals from G protein-coupled receptors to downstream G protein effectors (1, 2). Recently, a protein family, the RGS proteins (for Regulator of G protein Signaling), has been discovered; these proteins regulate G␣ subunits by acting as GTPase activating proteins (3-5). To date, at least 24 distinct RGS proteins have been found in mammals, but information on the connections of RGS proteins to specific signaling pathways and on the functional roles of RGS proteins in specific biological systems is still limited (3, 4).We have been interested in defining the G protein-mediated signaling pathways associated with intracellular membranes (6, 7). Previously, we identified GAIP (G␣ interacting protein), one of the founding members of the RGS protein family, and localized it to clathrin-coated vesicles in pituitary cells and hepatocytes, among others (6). Besides GAIP, additional RGS proteins have also been found in pituitary, liver, and other secretory cells (3). We have chosen RGS16 (ref. 8; ref. 9; ref. 10) for further study, because our interests focus on secretory cells and because RGS16 was shown to be highly expressed in mouse pituitary and liver (8). RGS16 has been shown to be a GTPase activating protein for members of the G␣i family in vitro (9, 11). However, little information is available concerning the interaction of RGS16 with molecules other than G␣ subunits.To define further signaling pathways involving RGS16, we used the yeast two-hybrid system to identify proteins that interact with RGS16. Herein, we report the discovery of an integral membrane protein MIR16 (for Membrane Interacting protein of RGS16), identified by screening a pituitary cell cDNA library with RGS16 as bait. Sequence analysis ind...

show abstract

Section: Discussionmentioning

confidence: 99%

Section: ϫ21mentioning

confidence: 99%

MIR16, a putative membrane glycerophosphodiester phosphodiesterase, interacts with RGS16

Zheng

Chen

Farquhar

2000

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Nevertheless, none of these activities have been characterized at the molecular level. Finally, in prokaryotes, a periplasmic GPX-PDE encoded by the glpQ gene was thoroughly described in Escherichia coli (Larson and van Loo-Bhattacharya, 1988;Tommassen et al, 1991).…”

Section: Originality Of Plant Gpc-pdementioning

confidence: 99%

Glycerophosphocholine Metabolism in Higher Plant Cells. Evidence of a New Glyceryl-Phosphodiester Phosphodiesterase

et al. 2002

View full text Add to dashboard Cite

Glycerophosphocholine (GroPCho) is a diester that accumulates in different physiological processes leading to phospholipid remodeling. However, very little is known about its metabolism in higher plant cells. 31 P-Nuclear magnetic resonance spectroscopy and biochemical analyses performed on carrot (Daucus carota) cells fed with GroPCho revealed the existence of an extracellular GroPCho phosphodiesterase. This enzymatic activity splits GroPCho into sn-glycerol-3-phosphate and free choline. In vivo, sn-glycerol-3-phosphate is further hydrolyzed into glycerol and inorganic phosphate by acid phosphatase. We visualized the incorporation and the compartmentation of choline and observed that the major choline pool was phosphorylated and accumulated in the cytosol, whereas a minor fraction was incorporated in the vacuole as free choline. Isolation of plasma membranes, culture medium, and cell wall proteins enabled us to localize this phosphodiesterase activity on the cell wall. We also report the existence of an intracellular glycerophosphodiesterase. This second activity is localized in the vacuole and hydrolyzes GroPCho in a similar fashion to the cell wall phosphodiesterase. Both extra-and intracellular phosphodiesterases are widespread among different plant species and are often enhanced during phosphate deprivation. Finally, competition experiments on the extracellular phosphodiesterase suggested a specificity for glycerophosphodiesters (apparent K m of 50 m), which distinguishes it from other phosphodiesterases previously described in the literature.Phospholipids play a key role in the architecture of eukaryote membranes. Membrane lipid composition is under tight regulation that involves both lipid biosynthesis and turnover. Phospholipid turnover may result from the action of acyl-transferases (Frentzen, 1993), phospholipases (Wang, 1993;Munnik et al., 1998), or lipolytic acyl-hydrolases (Huang, 1993. Among the catabolic products, acyl groups can be degraded by ␣-or ␤-oxidation and used as a respiratory substrates (Gerhardt, 1993) or for triacylglycerol synthesis (Frentzen, 1993;Ohlrogge and Browse, 1995). The phospholipid head groups are a source of glycerol, phosphate, or polar head moieties that can be reused directly in phospholipid synthesis (Kinney, 1993).In non-plant eukaryotes, phospholipid catabolism often produces glycerophosphodiesters. In yeast (Saccharomyces cerevisiae), glycerophosphodiesters are secreted in the extracellular medium and hydrolyzed at the outer surface of the cell (Patton et al., 1995;Dowd et al., 2001). In animal cells, glycerophosphodiesters, mainly glycerophosphocholine (GroPCho) are synthesized from phospholipids. In HeLa cells, GroPCho secretion was observed (Barburina and Jackowski, 1999). Moreover, GroPCho can accumulate in renal cells where its role as an osmoprotectant has been suggested (Zablocki et al., 1991; Bauernschmitt and Kinne, 1993). GroPCho concentration in renal cells is controlled by its enzymatic degradation rate, involving phosphodiesterase (Zablocki et al., 1...

show abstract

“…The glpTQ operon encodes glycerol-P permease (Eiglmeier et al, 1987) and a periplasmic phosphodiesterase specific for glycerophosphodiesters (Tommassen et al, 1991). The adjacent, divergently transcribed glpACB operon encodes the subunits of the anaerobic glycerol-P dehydrogenase (Cole et al, 1988).…”

Section: Introductionmentioning

confidence: 99%

Action at a distance for glp repressor control of glpTQ transcription in Escherichia coli K‐12

Yang

Gerhardt

Larson

1997

Molecular Microbiology

Self Cite

View full text Add to dashboard Cite

SummaryThe adjacent, divergently transcribed glpACB and glpTQ operons of Escherichia coli encode the anaerobic glycerol 3-phosphate dehydrogenase and glycerol 3-phosphate transporter/phosphodiesterase, respectively. These operons are negatively controlled by glp repressor binding to operators that overlap the glpA promoter elements. Using DNase I footprinting, three additional operators (O T 1-3) were identified at positions þ307 to þ359 within the glpT coding region. To assess a potential regulatory role for these remote operators in vivo, a glpT-lacZ transcriptional fusion containing all of the glpA and glpT operators was constructed. The response of this fusion to the glp repressor was compared to fusion constructs in which O T 1 and O T 3 were inactivated, either by deletion or by sitedirected mutagenesis. It was found that repression of glpT conferred by binding of glp repressor to glpA operators was increased about three-to fourfold upon introduction of the remote glpT operators. In addition, two integration host factor (IHF) binding sites were identified downstream of the glpT transcriptional start site at positions þ15 to þ51 and þ193 to þ227. A regulatory role for IHF was demonstrated by showing that repression of glpT mediated by GlpR was decreased about twofold in strains deficient in IHF and that mutations in IHF1 and/or IHF2 decreased repression about two-to threefold. The effect of IHF was apparent only when the remote operators were present. All of the results are consistent with a model of repression involving GlpR binding simultaneously to the glpA and remote glpT operators, with intervening DNA forming a loop.

show abstract

Characterization of two genes, glpQ and ugpQ, encoding glycerophosphoryl diester phosphodiesterases of Escherichia coli

Cited by 92 publications

References 32 publications

MIR16, a putative membrane glycerophosphodiester phosphodiesterase, interacts with RGS16

MIR16, a putative membrane glycerophosphodiester phosphodiesterase, interacts with RGS16

Glycerophosphocholine Metabolism in Higher Plant Cells. Evidence of a New Glyceryl-Phosphodiester Phosphodiesterase

Action at a distance for glp repressor control of glpTQ transcription in Escherichia coli K‐12

Contact Info

Product

Resources

About