title: A molecular modeling approach to understand the structure and conformation relationship of (GlcpA)Xylan.
abstract: The structure and conformation relationships of a heteropolysaccharide (GlcpA)Xylan in terms of various molecular weights, Xylp/GlcpA ratio and the distribution of GlcpA along xylan chain were investigated using computer modeling. The adiabatic contour maps of xylobiose, XylpXylp(GlcpA) and (GlcpA)XylpXylp(GlcpA) indicated that the insertion of the side group (GlcpA) influenced the accessible conformational space of xylobiose molecule. RIS-Metropolis Monte Carlo method indicated that insertion of GlcpA side chain induced a lowering effect of the calculated chain extension at low GlcpA:Xylp ratio (GlcpA:Xylp = 1:3). The chain, however, became extended when the ratio of GlcpA:Xylp above 2/3. It was also shown that the spatial extension of the polymer chains was dependent on the distribution of side chain: the random distribution demonstrated the most flexible structure compared to block and alternative distribution. The present studies provide a unique insight into the dependence of both side chain ratio and distribution on the stiffness and flexibility of various (GlcpA)Xylan molecules.
authors.affiliation: College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, Shaanxi 710119, China; Department of Food Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Qingbin
authors.initials: Q
authors.lastname: Guo
authors.affiliation: Department of Grain Science and Industry, Kansas State University, United States.
authors.forename: Ji
authors.initials: J
authors.lastname: Kang
authors.affiliation: School of Agriculture and Biology, Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Food Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada; Guelph Food Research Centre, Agriculture and Agri-Food Canada, Guelph, Ontario N1G 5C9, Canada. Electronic address: cuis@agr.gc.ca.
authors.forename: Steve W
authors.initials: SW
authors.lastname: Cui
authors.affiliation: College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, Shaanxi 710119, China. Electronic address: hxinzhong@126.com.
authors.forename: Xinzhong
authors.initials: X
authors.lastname: Hu
authors.affiliation: Department of Food Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada; Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Rickey Y
authors.initials: RY
authors.lastname: Yada
mesh_terms: D019306:Artemisia / Q000737:chemistry*; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009010:Monte Carlo Method; D012639:Seeds / Q000737:chemistry*; D014990:Xylans / Q000737:chemistry*
chemical_list: D014990:Xylans
keywords: Artemisia sphaerocephala Krasch; Computer modeling; Conformation; Polysaccharides; Xylan