Structural investigation of a glycoprotein from gum ghatti

Ji Kang; Steve W Cui; Qingbin Guo; Jie Chen; Qi Wang; Glyn O Phillips; John Nikiforuk

doi:10.1016/j.carbpol.2012.04.004

Structural investigation of a glycoprotein from gum ghatti

Carbohydr Polym. 2012 Jul 1;89(3):749-58. doi: 10.1016/j.carbpol.2012.04.004. Epub 2012 Apr 9.

Authors

Ji Kang¹, Steve W Cui², Qingbin Guo³, Jie Chen¹, Qi Wang³, Glyn O Phillips⁴, John Nikiforuk⁵

Affiliations

¹ State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214100, China.
² State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214100, China; Guelph Food Research Centre, Agriculture and Agri-Food Canada, Guelph, Ontario N1G 5C9, Canada.
³ Guelph Food Research Centre, Agriculture and Agri-Food Canada, Guelph, Ontario N1G 5C9, Canada.
⁴ Phillips Hydrocolloids Research Centre, Glyndwr University, Wrexham, Wales LL11 2AW, UK.
⁵ East Cereal and Oil Research Centre, Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada.

PMID: 24750858
DOI: 10.1016/j.carbpol.2012.04.004

Abstract

The glycoprotein structure of gum ghatti was investigated. The covalent bonding between polysaccharides and proteins was firstly confirmed by high performance size exclusion chromatography (HPSEC) using refractive index (RI) and UV detectors. Partial acid hydrolysis and enzymatic degradation were also utilized. Several structural fragments such as AraHex2-HexA-HexNAc, Hex4HexNAc2, AraHex4HexNAc, Hex10HexNAc and Hex4HexNAc-Asn were identified from MALDI-TOF spectrum; using 1D and 2D NMR spectra, the linkage site of amino acids and polysaccharides was determined as N-linked (Hex)n-GlcNAc-Asn. Combined with the polysaccharide structure obtained before, a glycoprotein structure model was proposed. It was composed of 1,6-linked galactose backbone, which were attached by numerous of sugar side chains and peptide chains.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Amino Acids / analysis
Carbon-13 Magnetic Resonance Spectroscopy
Chromatography, Gel
Chromatography, High Pressure Liquid
Glycoproteins / chemistry*
Hydrolysis
Plant Gums / chemistry*
Protein Conformation
Proton Magnetic Resonance Spectroscopy
Refractometry
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
Spectrophotometry, Ultraviolet

Substances

Amino Acids
Glycoproteins
Plant Gums
gum ghatti