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Cellulose

, Volume 26, Issue 1, pp 291–304 | Cite as

Impact of acidic pH on plant cell wall polysaccharide structure and dynamics: insights into the mechanism of acid growth in plants from solid-state NMR

  • Pyae Phyo
  • Ying Gu
  • Mei HongEmail author
Original Paper
  • 67 Downloads

Abstract

Acidification of plant primary cell walls causes cell wall expansion and plant growth. To understand how acidic pH affects the molecular structure and dynamics of wall polysaccharides, we have now characterized and compared Arabidopsis thaliana primary cell walls in neutral (pH 6.8) and acidic (pH 4.0) conditions using solid-state NMR spectroscopy. Quantitative 13C solid-state NMR spectra indicate that the pH 4.0 cell wall has neutral galacturonic acid residues in homogalacturonan (HG) and rhamnogalacturonan (RG). 13C INEPT spectra, which selectively detect highly dynamic polymers, indicate that some of the HG and RG chains in the interfibrillar region have become more dynamic in the acidic wall compared to the neutral cell wall, whereas other chains have become more rigid. Consistent with this increased dynamic heterogeneity, C–H dipolar couplings and 2D 13C–13C correlation spectra indicate that some of the HG backbones are partially aggregated in the acidic cell wall. Moreover, 2D correlation spectra measured with long mixing times indicate that the acidic cell wall has weaker cellulose–pectin interactions, and water-polysaccharide 1H spin diffusion data show that cellulose microfibrils are better hydrated at low pH. Taken together, these results indicate a cascade of chemical and conformational changes of wall polysaccharides due to cell wall acidification. These changes start with neutralization of the pectic polysaccharides, which disrupts calcium crosslinking of HG, causes partial aggregation of the interfibrillar HG, weakens cellulose–pectin interactions, and increases the hydration of both cellulose microfibrils and matrix polysaccharides. These molecular-level structural and dynamical changes are expected to facilitate polysaccharide slippage, which underlies cell wall loosening and expansion, and may occur both independent of and as a consequence of protein-mediated wall loosening.

Graphical abstract

Keywords

Plant primary cell wall Solid-state NMR Acidic pH Acid growth Cellulose–pectin interaction 

Abbreviations

Ara, A

Arabinose

CW

Cell wall

CP

Cross polarization

DP

Direct polarization

Gal

Galactose

GalA, GA

Galacturonic acid

HG

Homogalacturonan

INEPT

Insensitive nuclei enhanced by polarization transfer

i

Interior crystalline cellulose

MAS

Magic-angle spinning

PDSD

Proton-driven 13C–13C spin diffusion

RG-I

Rhamnogalacturonan I

Rha R

Rhamnose

SSNMR

Solid-state nuclear magnetic resonance

s

Surface amorphous cellulose

XyG

Xyloglucan

Xyl, x

Xylose

Notes

Acknowledgments

This research was supported by the Center for Lignocellulose Structure and Formation, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award # DE-SC0001090.

References

  1. Arsuffi G, Braybrook SA (2018) Acid growth: an ongoing trip. J Exp Bot 69:137–146CrossRefGoogle Scholar
  2. Bielecki A, Kolbert AC, Levitt MH (1989) Frequency-switched pulse sequences—homonuclear decoupling and dilute spin NMR in solids. Chem Phys Lett 155:341–346CrossRefGoogle Scholar
  3. Bosch M, Hepler PK (2005) Pectin methylesterases and pectin dynamics in pollen tubes. Plant Cell 17:3219–3226CrossRefGoogle Scholar
  4. Braybrook SA, Peaucelle A (2013) Mechano-chemical aspects of organ formation in Arabidopsis thaliana: the relationship between auxin and pectin. PLoS ONE 8:e57813CrossRefGoogle Scholar
  5. Cadars S et al (2007) The refocused INADEQUATE MAS NMR experiment in multiple spin-systems: interpreting observed correlation peaks and optimising lineshapes. J Magn Reson 188:24–34CrossRefGoogle Scholar
  6. Cavalier DM et al (2008) Disrupting two Arabidopsis thaliana xylosyltransferase genes results in plants deficient in xyloglucan, a major primary cell wall component. Plant Cell 20:1519–1537CrossRefGoogle Scholar
  7. Cosgrove DJ (2000) Loosening of plant cell walls by expansins. Nature 407:321–326CrossRefGoogle Scholar
  8. Cosgrove DJ (2005) Growth of the plant cell wall. Nat Rev Mol Cell Biol 6:850–861CrossRefGoogle Scholar
  9. Cosgrove DJ (2016) Catalysts of plant cell wall loosening. F1000Res 5:1–13CrossRefGoogle Scholar
  10. Cosgrove DJ (2018) Diffuse growth of plant cell walls. Plant Physiol 176:16–27CrossRefGoogle Scholar
  11. Cosgrove DJ, Bedinger P, Durachko DM (1997) Group I allergens of grass pollen as cell wall-loosening agents. Proc Natl Acad Sci USA 94:6559–6564CrossRefGoogle Scholar
  12. Dick-Perez M, Zhang YA, Hayes J, Salazar A, Zabotina OA, Hong M (2011) Structure and interactions of plant cell wall polysaccharides by two- and three-dimensional magic-angle-spinning solid-state NMR. Biochemistry 50:989–1000CrossRefGoogle Scholar
  13. Durachko DM, Cosgrove DJ (2009) Measuring plant cell wall extension (creep) induced by acidic pH and by alpha-expansin. J Vis Exp 25:1263Google Scholar
  14. Elena B, Lesage A, Steuernagel S, Bockmann A, Emsley L (2005) Proton to carbon-13 INEPT in solid-state NMR spectroscopy. J Am Chem Soc 127:17296–17302CrossRefGoogle Scholar
  15. Ezaki N, Kido N, Takahashi K, Katou K (2005) The role of wall Ca2+ in the regulation of wall extensibility during the acid-induced extension of soybean hypocotyl cell walls. Plant Cell Physiol 46:1831–1838CrossRefGoogle Scholar
  16. Hager A (2003) Role of the plasma membrane H+-ATPase in auxin-induced elongation growth: historical and new aspects. J Plant Res 116:483–505CrossRefGoogle Scholar
  17. Hager A, Menzel H, Krauss A (1971) Experiments and hypothesis concerning the primary action of auxin in elongation growth. Planta 100:47–75CrossRefGoogle Scholar
  18. Hediger S, Emsley L, Fischer M (1999) Solid-state NMR characterization of hydration effects on polymer mobility in onion cell-wall material. Carbohydr Res 322:102–112CrossRefGoogle Scholar
  19. Hong M, Gross JD, Rienstra CM, Griffin RG, Kumashiro KK, Schmidt-Rohr K (1997) Coupling amplification in 2D MAS NMR and its application to torsion angle determination in peptides. J Magn Reson 129:85–92CrossRefGoogle Scholar
  20. Kohn R, Kovac P (1978) Dissociation-constants of D-galacturonic and D-glucuronic acid and their O-methyl derivatives. Chem Pap 32:478–485Google Scholar
  21. Laskowski M, Biller S, Stanley K, Kajstura T, Prusty R (2006) Expression profiling of auxin-treated Arabidopsis roots: toward a molecular analysis of lateral root emergence. Plant Cell Physiol 47:788–792CrossRefGoogle Scholar
  22. Lesage A, Auger C, Caldarelli S, Emsley L (1997) Determination of through-bond carbon–carbon connectivities in solid-state NMR using the INADEQUATE experiment. J Am Chem Soc 119:7867–7868CrossRefGoogle Scholar
  23. Liepinsh E, Otting G (1996) Proton exchange rates from amino acid side chains–implications for image contrast. Magn Reson Med 35:30–42CrossRefGoogle Scholar
  24. Lüthen H, Bigdon M, Böttger M (1990) Reexamination of the acid growth theory of auxin action. Plant Physiol 93:931–939CrossRefGoogle Scholar
  25. Majda M, Robert S (2018) The role of auxin in cell wall expansion. Int J Mol Sci 19:1–21CrossRefGoogle Scholar
  26. Mcqueen-mason SJ, Cosgrove DJ (1995) Expansin mode of action on cell-walls—analysis of wall hydrolysis, stress-relaxation, and binding. Plant Physiol 107:87–100CrossRefGoogle Scholar
  27. Munowitz MG, Griffin RG, Bodenhausen G, Huang TH (1981) Two-dimensional rotational spin-echo nuclear magnetic-resonance in solids—correlation of chemical-shift and dipolar interactions. J Am Chem Soc 103:2529–2533CrossRefGoogle Scholar
  28. Park YB, Cosgrove DJ (2012a) Changes in cell wall biomechanical properties in the xyloglucan-deficient xxt1/xxt2 mutant of arabidopsis. Plant Physiol 158:465–475CrossRefGoogle Scholar
  29. Park YB, Cosgrove DJ (2012b) A revised architecture of primary cell walls based on biomechanical changes induced by substrate-specific endoglucanases. Plant Physiol 158:1933–1943CrossRefGoogle Scholar
  30. Phyo P, Wang T, Kiemle SN, O’Neill H, Pingali SV, Hong M, Cosgrove DJ (2017a) Gradients in wall mechanics and polysaccharides along growing inflorescence stems. Plant Physiol 175:1593–1607CrossRefGoogle Scholar
  31. Phyo P, Wang T, Xiao C, Anderson CT, Hong M (2017b) Effects of pectin molecular weight changes on the structure, dynamics, and polysaccharide interactions of primary cell walls of Arabidopsis thaliana: insights from solid-state NMR. Biomacromol 18:2937–2950CrossRefGoogle Scholar
  32. Prat R, Gueissaz MB, Goldberg R (1984) Effects of Ca-2+ and Mg-2+ on elongation and H+ secretion of vigna radiata hypocotyl sections. Plant Cell Physiol 25:1459–1467CrossRefGoogle Scholar
  33. Rienstra CM et al (2002) De novo determination of peptide structure with solid-state magic-angle spinning NMR spectroscopy. Proc Natl Acad Sci USA 99:10260–10265CrossRefGoogle Scholar
  34. Tepfer M, Cleland RE (1979) A comparison of acid-induced cell wall loosening in valonia ventricosa and in oat coleoptiles. Plant Physiol 63:898–902CrossRefGoogle Scholar
  35. Wang T, Hong M (2016) Solid-state NMR investigations of cellulose structure and interactions with matrix polysaccharides in plant primary cell walls. J Exp Bot 67:503–514CrossRefGoogle Scholar
  36. Wang T, Zabotina O, Hong M (2012) Pectin–cellulose interactions in the Arabidopsis primary cell wall from two-dimensional magic-angle-spinning solid-state nuclear magnetic resonance. Biochemistry 51:9846–9856CrossRefGoogle Scholar
  37. Wang T, Park YB, Caporini MA, Rosay M, Zhong LH, Cosgrove DJ, Hong M (2013) Sensitivity-enhanced solid-state NMR detection of expansin’s target in plant cell walls. Proc Natl Acad Sci USA 110:16444–16449CrossRefGoogle Scholar
  38. Wang T, Salazar A, Zabotina OA, Hong M (2014) Structure and dynamics of Brachypodium primary cell wall polysaccharides from two-dimensional 13C solid-state nuclear magnetic resonance spectroscopy. Biochemistry 53:2840–2854CrossRefGoogle Scholar
  39. Wang T, Park YB, Cosgrove DJ, Hong M (2015) Cellulose–pectin spatial contacts are inherent to never-dried Arabidopsis thaliana primary cell walls: evidence from solid-state NMR. Plant Physiol 168:871–883CrossRefGoogle Scholar
  40. Wang T, Chen Y, Tabuchi A, Hong M, Cosgrove DJ (2016a) The target of beta-expansin EXPB1 in maize cell walls from binding and solid-state NMR studies. Plant Physiol 172:2107–2119CrossRefGoogle Scholar
  41. Wang T, Phyo P, Hong M (2016b) Multidimensional solid-state NMR spectroscopy of plant cell walls. Solid State Nucl Magn Reson 78:56–63CrossRefGoogle Scholar
  42. White PB, Wang T, Park YB, Cosgrove DJ, Hong M (2014) Water-polysaccharide interactions in the primary cell wall of Arabidopsis thaliana from polarization transfer solid-state NMR. J Am Chem Soc 136:10399–10409CrossRefGoogle Scholar
  43. Xiao C, Zhang T, Zheng Y, Cosgrove DJ, Anderson CT (2016) Xyloglucan deficiency disrupts microtubule stability and cellulose biosynthesis in Arabidopsis, altering cell growth and morphogenesis. Plant Physiol 170:234–249CrossRefGoogle Scholar
  44. Yu B, van Ingen H, Vivekanandan S, Rademacher C, Norris SE, Freedberg DI (2012) More accurate 1 J(CH) coupling measurement in the presence of 3 J(HH) strong coupling in natural abundance. J Magn Reson 215:10–22CrossRefGoogle Scholar

Copyright information

© Springer Nature B.V. 2018

Authors and Affiliations

  1. 1.Department of ChemistryMassachusetts Institute of TechnologyCambridgeUSA
  2. 2.Department of Biochemistry and Molecular BiologyPennsylvania State UniversityUniversity ParkUSA

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