Application of recent advances in hydrodynamic methods for characterising mucins in solution

Almutairi, Fahad M.; Cifre, Jose-Gines Hernandez; Adams, Gary G.; K�k, M. Samil; Mackie, Alan R.; de la Torre, Jose Garcia; Harding, Stephen E.

Abstract

Mucins are the primary macromolecular component of mucus—nature’s natural lubricant—although they are poorly characterised heterogeneous substances. Recent advances in hydrodynamic methodology now offer the opportunity for gaining a better understanding of their solution properties. In this study a combination of such methods was used to provide increased understanding of a preparation of porcine intestinal mucin (PIM), MUC2 mucin, in terms of both heterogeneity and quantification of conformational flexibility. The new sedimentation equilibrium algorithm SEDFIT-MSTAR is applied to yield a weight average (over the whole distribution) molar mass of 7.1 × 106 g mol−1, in complete agreement with size exclusion chromatography coupled with multi-angle light scattering (SEC-MALS), which yielded a value of 7.2 × 106 g mol−1. Sedimentation velocity profiles show mucin to be very polydisperse, with a broad molar mass distribution obtained using the Extended Fujita algorithm, consistent with the elution profiles from SEC-MALS. On-line differential pressure viscometry coupled to the SEC-MALS was used to obtain the intrinsic viscosity [η] as a function of molar mass. These data combined with sedimentation coefficient data into the global conformation algorithm HYDFIT show that PIM has a flexible linear structure, with persistence length Lp ~10 nm and mass per unit length, ML ~2380 g mol−1 nm−1, consistent with a Wales-van Holde ratio of ~1.2 obtained from the concentration dependence of the sedimentation coefficient.

Citation

Almutairi, F. M., Cifre, J. H., Adams, G. G., Kök, M. S., Mackie, A. R., de la Torre, J. G., & Harding, S. E. (2016). Application of recent advances in hydrodynamic methods for characterising mucins in solution. European Biophysics Journal, 45(1), 45-54. https://doi.org/10.1007/s00249-015-1075-0

• Journal Article Type: Article
• Acceptance Date: Aug 13, 2015
• Online Publication Date: Nov 1, 2015
• Publication Date: Jan 31, 2016
• Deposit Date: May 10, 2017
• Journal: European Biophysics Journal
• Print ISSN: 0175-7571
• Electronic ISSN: 1432-1017
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 45
• Issue: 1
• Pages: 45-54
• DOI: https://doi.org/10.1007/s00249-015-1075-0
• Keywords: Mucin; Molar mass; Conformation; Novel hydrodynamic methods
• Public URL: https://nottingham-repository.worktribe.com/output/771110
• Publisher URL: http://link.springer.com/article/10.1007%2Fs00249-015-1075-0
• Additional Information: The final publication is available at Springer via http://dx.doi.org/10.1007/s00249-015-1075-0