title: Amino acid residues important for D-galactose recognition by the F-type lectin, Ranaspumin-4.
creator: Sharma, Shailza
creator: Mahajan, Sonal
creator: Sunsunwal, Sonali
creator: Khairnar, Aasawari
creator: Ramya, T N C
subject: QR Microbiology
description: F-type lectins are typically L-fucose binding proteins with characteristic L-fucose-binding and calciumbinding sequence motifs, and an F-type lectin fold. An exception is Ranaspumin-4, an F-type lectin of the Tungra frog, Engystomops pustulosus. Ranaspumin-4 is D-galactose specific and does not bind to L-fucose although it has the conserved L-fucose binding sequence motif and shares overall sequence similarity with other F-type lectins. Here, we report the detailed glycan-binding profile of wild-type Ranaspumin-4 using hemagglutination inhibition assays, flow cytometry assays and enzyme-linked lectin assays, and identify residues important for D-galactose recognition using rational site-directed mutagenesis. We demonstrate that Ranaspumin-4 binds to terminal D-galactose in alpha or beta linkage with preference for alpha 1-3, alpha 1-4,beta 1-3, and beta 1-4 linkages. Further, we find that a methionine residue (M31) in Ranaspumin-4 that occurs in place of a conserved Gln residue (in other F-type lectins), supports D-galactose recognition. Resides Q42 and F156 also likely aid in D-galactose recognition. (C) 2020 Elsevier Inc. All rights reserved.
publisher: Elsevier Science/Academic Press
date: 2020-10-29
type: Article
type: PeerReviewed
identifier:   Sharma, Shailza and Mahajan, Sonal and Sunsunwal, Sonali and Khairnar, Aasawari and Ramya, T N C  (2020) Amino acid residues important for D-galactose recognition by the F-type lectin, Ranaspumin-4.  Biochemical and biophysical research communications, 532 (1).  pp. 54-59.  ISSN 0006-291X     
relation: http://crdd.osdd.net/open/2611/