TY - JOUR
T1 - Chemical and in situ characterization of macromolecular components of the cell walls from the green seaweed Codium fragile
AU - Estevez, José Manuel
AU - Fernández, Paula Virginia
AU - Kasulin, Luciana
AU - Dupree, Paul
N1 - Funding Information:
The authors gratefully acknowledge A. S. Cerezo for the critical reading of the manuscript and C. Somerville for providing most of the antibodies used in this study and also making available to J.M.E. the infrastructure of Carnegie Institution of Washington (Stanford University). Without his support, this work would have not been possible. The authors also thank the assistance of X.L. Yu for the PACE experiments, M.C. Martin (ALS, Berkeley, CA), and T.K. Raab with the SR-FTIR microspectroscopy analysis (ALS, Berkeley, CA) and CG-MS, and finally, S. Lynch for the NMR experiment (NMR Facility, Stanford University). The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sci- ences, the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
PY - 2009/2/3
Y1 - 2009/2/3
N2 - A comprehensive analysis of the carbohydrate-containing macromolecules from the coencocytic green seaweed Codium fragile and their arrangement in the cell wall was carried out. Cell walls in this seaweed are highly complex structures composed of 31% (w/w) of linear (1→4)-β-D-mannans, 9% (w/w) of pyruvylated arabinogalactan sulfates (pAGS), and low amounts of hydroxyproline rich-glycoprotein epitopes (HRGP). In situ chemical imaging by synchrotron radiation Fourier transform infrared (SR-FTIR) microspectroscopy and by immunolabeling using antibodies against specific cell wall carbohydrate epitopes revealed that β-D-mannans and pAGS are placed in the middle part of the cell wall, whereas HRGP epitopes (arabinogalactan proteins (AGPs) and extensins) are located on the wall boundaries, especially in the utricle apical zone. pAGS are sulfated at C-2 and/or C-4 of the 3-linked β-L-arabinopyranose units and at C-4 and/or C-6 of the 3-linked β-D-galactopyranose residues. In addition, high levels of ketals of pyruvic acid were found mainly at 3,4- of some terminal β-D-Gal p units forming a five-membered ring. Ramification was found at some C-6 of the 3-linked β-D-Gal p units. In agreement with the immunolabeled AGP epitopes, a nonsulfated branched furanosidic arabinan with 5-linked α-L-Ara f, 3,5-linked α-L-Ara f, and terminal α-L-Ara f units and a nonsulfated galactan structure composed of 3-(3,6)-linked β-D-Gal p residues, both typical of type-II AG glycans were found, suggesting that AGP structures are present at low levels in the cell walls of this seaweed. Based on this study, it is starting to emerge that Codium has developed unique cell wall architecture, when compared, not only with that of vascular plants, but also with other related green seaweeds and algae.
AB - A comprehensive analysis of the carbohydrate-containing macromolecules from the coencocytic green seaweed Codium fragile and their arrangement in the cell wall was carried out. Cell walls in this seaweed are highly complex structures composed of 31% (w/w) of linear (1→4)-β-D-mannans, 9% (w/w) of pyruvylated arabinogalactan sulfates (pAGS), and low amounts of hydroxyproline rich-glycoprotein epitopes (HRGP). In situ chemical imaging by synchrotron radiation Fourier transform infrared (SR-FTIR) microspectroscopy and by immunolabeling using antibodies against specific cell wall carbohydrate epitopes revealed that β-D-mannans and pAGS are placed in the middle part of the cell wall, whereas HRGP epitopes (arabinogalactan proteins (AGPs) and extensins) are located on the wall boundaries, especially in the utricle apical zone. pAGS are sulfated at C-2 and/or C-4 of the 3-linked β-L-arabinopyranose units and at C-4 and/or C-6 of the 3-linked β-D-galactopyranose residues. In addition, high levels of ketals of pyruvic acid were found mainly at 3,4- of some terminal β-D-Gal p units forming a five-membered ring. Ramification was found at some C-6 of the 3-linked β-D-Gal p units. In agreement with the immunolabeled AGP epitopes, a nonsulfated branched furanosidic arabinan with 5-linked α-L-Ara f, 3,5-linked α-L-Ara f, and terminal α-L-Ara f units and a nonsulfated galactan structure composed of 3-(3,6)-linked β-D-Gal p residues, both typical of type-II AG glycans were found, suggesting that AGP structures are present at low levels in the cell walls of this seaweed. Based on this study, it is starting to emerge that Codium has developed unique cell wall architecture, when compared, not only with that of vascular plants, but also with other related green seaweeds and algae.
KW - β-mannan
KW - Codium cell wall
KW - Green seaweed
KW - HRGP epitope
KW - Pyruvylated arabinogalactan sulfate
UR - http://www.scopus.com/inward/record.url?scp=58949102958&partnerID=8YFLogxK
U2 - 10.1093/glycob/cwn101
DO - 10.1093/glycob/cwn101
M3 - Article
C2 - 18832454
AN - SCOPUS:58949102958
SN - 0959-6658
VL - 19
SP - 212
EP - 228
JO - Glycobiology
JF - Glycobiology
IS - 3
ER -