Mannan-binding lectin of the sea urchin Strongylocentrotus nudus.
A novel lectin specific to low-branched mannans (MBL-SN) was isolated from coelomic plasma of the sea urchin Strongylocentrotus nudus by combining anion-exchange liquid chromatography on DEAE Toyopearl 650 M, affinity chromatography on mannan-Sepharose and gel filtration on the Sephacryl S-200. The molecular mass of MBL-SN was estimated by sodium dodecyl sulphate polyacrylamide gel electrophoresis under non-reducing conditions to be about 34 kDa. MBL-SN was shown to be a dimer with two identical subunits of about 17 kDa. The native MBL-SN exists as a tetramer. The physico-chemical properties of MBL-SN indicate that it belongs to C-type mannan-binding lectins. The cDNA encoding MBL-SN was cloned from the total cDNA of S. nudus coelomocytes and encodes a 17-kDa protein of 144 amino acid residues that contains a single carbohydrate-recognition domain of C-type lectins. Prediction of the MBL-SN tertiary structure using comparative modelling revealed that MBL-SN is an α/β-protein with eight β-strands and two α-helices. Comparison of the MBL-SN model with available three-dimensional structures of C-type lectins revealed that they share a common fold pattern.
G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, Stoletya Vladivostoku Str. 159, Vladivostok 690022, Russia. aabulgakov@yahoo.com
Aleksandr A
AA
Bulgakov
Marina G
MG
Eliseikina
Svetlana N
SN
Kovalchuk
Irina Yu
IY
Petrova
Galina N
GN
Likhatskaya
Ekaterina V
EV
Shamshurina
Valery A
VA
Rasskazov
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002118:Calcium / Q000378:metabolism; D002846:Chromatography, Affinity; D002847:Chromatography, Agarose; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003429:Cross Reactions; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007150:Immunohistochemistry; D037601:Mannose-Binding Lectin / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D047269:Strongylocentrotus / Q000235:genetics* / Q000276:immunology; D013696:Temperature
D037601:Mannose-Binding Lectin; D002118:Calcium