title: Identification of the S-layer glycoproteins and their covalently linked glycans in the halophilic archaeon Haloarcula hispanica.
abstract: Haloarcula hispanica is one of members of the Halobacteriaceae, which displays particularly low restriction activity and is therefore important as one of the most tractable haloarchaea for archaeal genetic research. Although the Har. hispanica S-layer protein has been reported glycosylated, the S-layer glycoprotein and its glycosylation have not been investigated yet. In this study, the S-layer proteins of Har. hispanica were extracted and characterized. The S-layer was found containing two different glycoproteins which shared highly similar amino acid sequences. The genes coding for these two S-layer glycoproteins were found next to each other in the genome. Moreover, the N- and O-linked glycans were released from these two S-layer glycoproteins for structural determination. Based on the mass spectrometry and nuclear magnetic resonance, the N-glycan was determined as a branched trisaccharide containing a 225 Da residue corresponded to a 2-amino-6-sulfo-2, 6-dideoxy-quinovose, which was the first time that a naturally occurring form of sulfoquinovosamine was identified. Besides, the O-glycan was characterized as a Glcα-1,4-Gal disaccharide by mass spectrometry combined with monosaccharide composition analysis and glycosidase treatment. The determination of the N- and O-glycan structure will be helpful for studying the diverse protein glycosylation pathways in archaea utilizing H. hispanica as a new model.
authors.affiliation: State Key Laboratory of Mycology University of Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Mycology.
authors.forename: Yang
authors.initials: Y
authors.lastname: Lü
authors.affiliation: State Key Laboratory of Mycology.
authors.forename: Jinwei
authors.initials: J
authors.lastname: Ren
authors.affiliation: Educational Ministry Key Laboratory of Resource Biology and Biotechnology in Western China, Life Science College, Northwest University, Xi'an 710069, China.
authors.forename: Zhongfu
authors.initials: Z
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Yuanming
authors.initials: Y
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Han
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Xiang
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Yuguo
authors.initials: Y
authors.lastname: Du
authors.affiliation: State Key Laboratory of Mycology jinc@im.ac.cn.
authors.forename: Cheng
authors.initials: C
authors.lastname: Jin
mesh_terms: D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry* / Q000378:metabolism; D006023:Glycoproteins / Q000737:chemistry* / Q000378:metabolism; D019613:Haloarcula / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000737:chemistry
chemical_list: D019843:Archaeal Proteins; D006023:Glycoproteins; D011134:Polysaccharides
keywords: Haloarcula hispanica; S-layer glycoprotein; oligosaccharide; structure