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Structural Basis for Feed-Forward Transcriptional Regulation of Membrane Lipid Homeostasis in


The biosynthesis of membrane lipids is an essential pathway for virtually all bacteria. Despite its potential importance for the development of novel antibiotics, little is known about the underlying signaling mechanisms that allow bacteria to control their membrane lipid composition within narrow limits. Recent studies disclosed an elaborate feed-forward system that senses the levels of malonyl-CoA and modulates the transcription of genes that mediate fatty acid and phospholipid synthesis in many Gram-positive bacteria including several human pathogens. A key component of this network is FapR, a transcriptional regulator that binds malonyl-CoA, but whose mode of action remains enigmatic. We report here the crystal structures of FapR from Staphylococcus aureus (SaFapR) in three relevant states of its regulation cycle. The repressor-DNA complex reveals that the operator binds two SaFapR homodimers with different affinities, involving sequence-specific contacts from the helix-turn-helix motifs to the major and minor grooves of DNA. In contrast with the elongated conformation observed for the DNA-bound FapR homodimer, binding of malonyl-CoA stabilizes a different, more compact, quaternary arrangement of the repressor, in which the two DNA-binding domains are attached to either side of the central thioesterase-like domain, resulting in a non-productive overall conformation that precludes DNA binding. The structural transition between the DNA-bound and malonyl-CoA-bound states of SaFapR involves substantial changes and large (>30 Å) inter-domain movements; however, both conformational states can be populated by the ligand-free repressor species, as confirmed by the structure of SaFapR in two distinct crystal forms. Disruption of the ability of SaFapR to monitor malonyl-CoA compromises cell growth, revealing the essentiality of membrane lipid homeostasis for S. aureus survival and uncovering novel opportunities for the development of antibiotics against this major human pathogen.


Vyšlo v časopise: Structural Basis for Feed-Forward Transcriptional Regulation of Membrane Lipid Homeostasis in. PLoS Pathog 9(1): e32767. doi:10.1371/journal.ppat.1003108
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.ppat.1003108

Souhrn

The biosynthesis of membrane lipids is an essential pathway for virtually all bacteria. Despite its potential importance for the development of novel antibiotics, little is known about the underlying signaling mechanisms that allow bacteria to control their membrane lipid composition within narrow limits. Recent studies disclosed an elaborate feed-forward system that senses the levels of malonyl-CoA and modulates the transcription of genes that mediate fatty acid and phospholipid synthesis in many Gram-positive bacteria including several human pathogens. A key component of this network is FapR, a transcriptional regulator that binds malonyl-CoA, but whose mode of action remains enigmatic. We report here the crystal structures of FapR from Staphylococcus aureus (SaFapR) in three relevant states of its regulation cycle. The repressor-DNA complex reveals that the operator binds two SaFapR homodimers with different affinities, involving sequence-specific contacts from the helix-turn-helix motifs to the major and minor grooves of DNA. In contrast with the elongated conformation observed for the DNA-bound FapR homodimer, binding of malonyl-CoA stabilizes a different, more compact, quaternary arrangement of the repressor, in which the two DNA-binding domains are attached to either side of the central thioesterase-like domain, resulting in a non-productive overall conformation that precludes DNA binding. The structural transition between the DNA-bound and malonyl-CoA-bound states of SaFapR involves substantial changes and large (>30 Å) inter-domain movements; however, both conformational states can be populated by the ligand-free repressor species, as confirmed by the structure of SaFapR in two distinct crystal forms. Disruption of the ability of SaFapR to monitor malonyl-CoA compromises cell growth, revealing the essentiality of membrane lipid homeostasis for S. aureus survival and uncovering novel opportunities for the development of antibiotics against this major human pathogen.


Zdroje

1. CampbellJW, CronanJEJr (2011) Bacterial fatty acid biosynthesis: targets for antibacterial drug discovery. Annu Rev Microbiol 55: 305–332.

2. ZhangYM, RockCO (2008) Membrane lipid homeostasis in bacteria. Nat Rev Microbiol 6: 222–233.

3. OverathP, PauliG, SchairerHU (1969) Fatty acid degradation in Escherichia coli. An inducible acyl-CoA synthetase, the mapping of old-mutations, and the isolation of regulatory mutants. Eur J Biochem 7: 559–574.

4. DiRussoCC, NunnWD (1985) Cloning and characterization of a gene (fadR) involved in regulation of fatty acid metabolism in Escherichia coli. J Bacteriol 161: 583–588.

5. HenryMF, CronanJEJr (1991) Escherichia coli transcription factor that both activates fatty acid synthesis and represses fatty acid degradation. J Mol Biol 222: 843–849.

6. HenryMF, CronanJEJr (1992) A new mechanism of transcriptional regulation: release of an activator triggered by small molecule binding. Cell 70: 671–67.

7. LuYJ, ZhangYM, RockCO (2004) Product diversity and regulation of type II fatty acid synthases. Biochem Cell Biol 82: 145–155.

8. CronanJEJr, SubrahmanyamS (1998) FadR, transcriptional co-ordination of metabolic expediency. Mol Microbiol 29: 937–943.

9. DiRussoCC, HeimertTL, MetzgerAK (1992) Characterization of FadR, a global transcriptional regulator of fatty acid metabolism in Escherichia coli. Interaction with the fadB promoter is prevented by long chain fatty acyl coenzyme A. J Biol Chem 267: 8685–8691.

10. DiRussoCC, TsvetnitskyV, HojrupP, KnudsenJ (1998) Fatty acyl-CoA binding domain of the transcription factor FadR. Characterization by deletion, affinity labeling, and isothermal titration calorimetry. J Biol Chem 273: 33652–33659.

11. RamanN, DiRussoCC (1995) Analysis of acyl coenzyme A binding to the transcription factor FadR and identification of amino acid residues in the carboxyl terminus required for ligand binding. J Biol Chem 270: 1092–1097.

12. van AaltenDM, DiRussoCC, KnudsenJ (2001) The structural basis of acyl coenzyme A-dependent regulation of the transcription factor FadR. EMBO J 20: 2041–2050.

13. van AaltenDM, DiRussoCC, KnudsenJ, WierengaRK (2000) Crystal structure of FadR, a fatty acid-responsive transcription factor with a novel acyl coenzyme A-binding fold. EMBO J 19: 5167–5177.

14. XuY, HeathRJ, LiZ, RockCO, WhiteSW (2001) The FadR.DNA complex. Transcriptional control of fatty acid metabolism in Escherichia coli. J Biol Chem 276: 17373–17379.

15. ZhuK, ChoiKH, SchweizerHP, RockCO, ZhangYM (2006) Two aerobic pathways for the formation of unsaturated fatty acids in Pseudomonas aeruginosa. Mol Microbiol 60: 260–273.

16. ZhangYM, ZhuK, FrankMW, RockCO (2007) A Pseudomonas aeruginosa transcription factor that senses fatty acid structure. Mol Microbiol 66: 622–632.

17. MillerDJ, ZhangYM, SubramanianC, RockCO, WhiteSW (2010) Structural basis for the transcriptional regulation of membrane lipid homeostasis. Nat Struct Mol Biol 17: 971–975.

18. SchujmanGE, PaolettiL, GrossmanAD, de MendozaD (2003) FapR, a bacterial transcription factor involved in global regulation of membrane lipid biosynthesis. Dev Cell 4: 663–672.

19. SchujmanGE, de MendozaD (2008) Regulation of type II fatty acid synthase in Gram-positive bacteria. Curr Opin Microbiol 11: 148–152.

20. SchujmanGE, GuerinM, BuschiazzoA, SchaefferF, LlarrullLl, et al. (2006) Structural basis of lipid biosynthesis regulation in Gram-positive bacteria. EMBO J 25: 4074–4083.

21. LeesongM, HendersonBS, GilligJR, SchwabJM, SmithJL (1996) Structure of a dehydratase-isomerase from the bacterial pathway for biosynthesis of unsaturated fatty acids: two catalytic activities in one active site. Structure 4: 253–264.

22. LiJ, DerewendaU, DauterZ, SmithS, DerewendaZS (2000) Crystal structure of the Escherichia coli thioesterase II, a homolog of the human Nef binding enzyme. Nat Struct Biol 7: 555–559.

23. DillonSC, BatemanA (2004) The Hotdog fold: wrapping up a superfamily of thioesterases and dehydratases. BMC Bioinformatics 5: 109.

24. PiduguLS, MaityK, RamaswamyK, SuroliaN, SugunaK (2009) Analysis of proteins with the ‘hot dog’ fold: prediction of function and identification of catalytic residues of hypothetical proteins. BMC Struct Biol 9: 37.

25. LowyFD (1998) Staphylococcus aureus infections. N Engl J Med 339: 520–532.

26. DavidMZ, DaumRS (2010) Community-associated methicillin-resistant Staphylococcus aureus: epidemiology and clinical consequences of an emerging epidemic. Clin Microbiol Rev 23: 616–687.

27. DeleoFR, OttoM, KreiswirthBN, ChambersHF (2010) Community-associated meticillin-resistant Staphylococcus aureus. Lancet 375: 1557–1568.

28. MartinezMA, et al. (2010) A novel role of malonyl-ACP in lipid homeostasis. Biochemistry 49: 3161–3167.

29. OrthP, SchnappingerD, HillenW, SaengerW, HinrichsW (2000) Structural basis of gene regulation by the tetracycline inducible Tet repressor-operator system. Nat Struct Biol 7: 215–219.

30. LewisM, et al. (1996) Crystal structure of the lactose operon repressor and its complexes with DNA and inducer. Science 271: 1247–1254.

31. BrinsterS, et al. (2009) Type II fatty acid synthesis is not a suitable antibiotic target for Gram-positive pathogens. Nature 458: 83–86.

32. ParsonsJB, FrankMW, SubramanianC, SaenkhamP, RockCO (2011) Metabolic basis for the differential susceptibility of Gram-positive pathogens to fatty acid synthesis inhibitors. Proc Natl Acad Sci U S A 108: 15378–15383.

33. VolkmanBF, LipsonD, WemmerDE, KernD (2001) Two-state allosteric behavior in a single-domain signaling protein. Science 291: 2429–2433.

34. GambinY, et al. (2009) Direct single-molecule observation of a protein living in two opposed native structures. Proc Natl Acad Sci U S A 106: 10153–10158.

35. ParsonsJB, RockCO (2011) Is bacterial fatty acid synthesis a valid target for antibacterial drug discovery? Curr Opin Microbiol 14: 544–549.

36. BrinsterS, et al. (2010) Essentiality of FASII pathway for Staphylococcus aureus. Nature 463: E4–E5.

37. PaolettiL, LuYJ, SchujmanGE, de MendozaD, RockCO (2007) Coupling of fatty acid and phospholipid synthesis in Bacillus subtilis. J Bacteriol 189: 5816–5824.

38. LuYJ, ZhangYM, GrimesKD, QiJ, LeeRE, RockCO (2006) Acyl-phosphates initiate membrane phospholipid synthesis in Gram-positive pathogens. Mol Cell 23: 765–72.

39. AltenbernRA (1977) Cerulenin-inhibited cells of Staphylococcus aureus resume growth when supplemented with either a saturated or an unsaturated fatty acid. Antimicrob Agents Chemother 11: 574–576.

40. ZhangYM, RockCO (2009) Transcriptional regulation in bacterial membrane lipid synthesis. J Lipid Res 50 Suppl: S115–119.

41. RaghowR, YellaturuC, DengX, ParkEA, ElamMB (2008) SREBPs: the crossroads of physiological and pathological lipid homeostasis. Trends Endocrinol Metab 19: 65–73.

42. HerbertS, et al. (2010) Repair of global regulators in Staphylococcus aureus 8325 and comparative analysis with other clinical isolates. Infect Immun 78: 2877–2889.

43. SchneewindO, ModelP, FischettiVA (1992) Sorting of protein A to the staphylococcal cell wall. Cell 70: 267–281.

44. KabschW (2010) Xds. Acta Crystallogr D Biol Crystallogr 66: 125–132.

45. Leslie AGW (2009) iMosflm, version 1.0.4. MRC-LMB, Cambridge, UK.

46. Collaborative Computational Project (1994) The CCP4 suite: programs for protein crystallography. Acta Crystallogr D Biol Crystallogr 50: 760–763.

47. TrapaniS, NavazaJ (2008) AMoRe: classical and modern. Acta Crystallogr D Biol Crystallogr 64: 11–16.

48. SheldrickGM (2008) A short history of SHELX. Acta Crystallogr A 64: 112–122.

49. BricogneG, VonrheinC, FlensburgC, SchiltzM, PaciorekW (2003) Generation, representation and flow of phase information in structure determination: recent developments in and around SHARP 2.0. Acta Crystallogr D Biol Crystallogr 59: 2023–2030.

50. MurshudovGN, VaginAA, DodsonEJ (1997) Refinement of macromolecular structures by the maximum-likelihood method. Acta Crystallogr D Biol Crystallogr 53: 240–255.

51. Bricogne G, Blanc E, Brandl M, Flensburg C, Keller P, et al.. (2009). BUSTER. Version 2.9.3. Cambridge, UK: Global Phasing Ltd.

52. EmsleyP, LohkampB, ScottWG, CowtanK (2010) Features and development of Coot. Acta Crystallogr D Biol Crystallogr 66: 486–501.

53. DavisIW, Leaver-FayA, ChenVB, BlockJN, KapralGJ, et al. (2007) MolProbity: all-atom contacts and structure validation for proteins and nucleic acids. Nucleic Acids Res 35: W375–W383.

54. DeLano WL (2002) The PyMOL molecular graphics system. Palo Alto, CA USA: DeLano Scientific.

55. LuXJ, OlsonWK (2003) 3DNA: a software package for the analysis, rebuilding and visualization of three-dimensional nucleic acid structures. Nucleic Acids Res 31: 5108–5121.

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Hygiena a epidemiológia Infekčné lekárstvo Laboratórium

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PLOS Pathogens


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