Sequence analysis of the pyruvylated galactan sulfate-derived oligosaccharides by negative-ion electrospray tandem mass spectrometry

Na Li; Wenjun Mao; Xue Liu; Shuyao Wang; Zheng Xia; Sujian Cao; Lin Li; Qi Zhang; Shan Liu

doi:10.1016/j.carres.2016.07.018

Sequence analysis of the pyruvylated galactan sulfate-derived oligosaccharides by negative-ion electrospray tandem mass spectrometry

Carbohydr Res. 2016 Oct 4:433:80-8. doi: 10.1016/j.carres.2016.07.018. Epub 2016 Jul 20.

Authors

Na Li¹, Wenjun Mao², Xue Liu³, Shuyao Wang³, Zheng Xia³, Sujian Cao³, Lin Li³, Qi Zhang³, Shan Liu³

Affiliations

¹ Key Laboratory of Marine Drugs, Ministry of Education, Institute of Marine Drug and Food, Ocean University of China, Qingdao 266003, People's Republic of China; Department of Food and Biochemical Engineering, Yantai Vocational College, Yantai 264670, People's Republic of China.
² Key Laboratory of Marine Drugs, Ministry of Education, Institute of Marine Drug and Food, Ocean University of China, Qingdao 266003, People's Republic of China. Electronic address: wenjunmqd@hotmail.com.
³ Key Laboratory of Marine Drugs, Ministry of Education, Institute of Marine Drug and Food, Ocean University of China, Qingdao 266003, People's Republic of China.

PMID: 27471831
DOI: 10.1016/j.carres.2016.07.018

Abstract

Five sulfated oligosaccharide fragments, F1-F5, were prepared from a pyruvylated galactan sulfate from the green alga Codium divaricatum, by partial depolymerization using mild acid hydrolysis and purification with gel-permeation chromatography. Negative-ion electrospray tandem mass spectrometry with collision-induced dissociation (ES-CID-MS/MS) is attempted for sequence determination of the sulfated oligosaccharides. The sequence of F1 with homogeneous disaccharide composition was first characterized to be Galp-(4SO4)-(1 → 3)-Galp by detailed nuclear magnetic resonance spectroscopic analyses. The fragmentation pattern of F1 in the product ion spectra was established on the basis of negative-ion ES-CID MS/MS, which was then applied to sequence analysis of other sulfated oligosaccharides. The sequences of F2 and F3 were deduced to be Galp-(4SO4)-(1 → 3)-Galp-(1 → 3)-Galp-(1 → 3)-Galp and 3,4-O-(1-carboxyethylidene)-Galp-(6SO4)-(1 → 3)-Galp, respectively. The sequences of major fragments in F4 and F5 were also deduced. The investigation demonstrated that negative-ion ES-CID-MS/MS was an efficient method for the sequence analysis of the pyruvylated galactan sulfate-derived oligosaccharides which revealed the patterns of substitution and glycosidic linkages. The pyruvylated galactan sulfate-derived oligosaccharides were novel sulfated oligosaccharides different from other algal polysaccharide-derived oligosaccharides.

Keywords: 1-Phenyl-3-methyl-5-pyrazolone (PubChem CID: 90474051); Acetonitrile (PubChem CID: 6342); Ammonium bicarbonate (PubChem CID: 14013); Barium rhodizonic acid (PubChem CID: 45048930); Codium divaricatum; D-galactose (PubChem CID: 6036); Deuterium oxide (PubChem CID: 24602); ES-CID-MS/MS; Oligosaccharides; Potassium bromide (PubChem CID: 253877); Pyruvylated galactan sulfate; Sequence; Sodium hydroxide (PubChem CID: 14798); Sulfuric acid (PubChem CID: 1118); Trifluoroacetic acid (PubChem CID: 6422).

MeSH terms

Carbohydrate Sequence
Galactans / chemistry
Oligosaccharides / analysis*
Oligosaccharides / chemistry
Pyruvates / chemistry*
Spectrometry, Mass, Electrospray Ionization / methods*
Sulfates / chemistry*
Tandem Mass Spectrometry

Substances

Galactans
Oligosaccharides
Pyruvates
Sulfates