Exquisite binding specificity of <Emphasis Type="Italic">Sclerotium rolfsii</Emphasis> lectin toward TF-related O-linked mucin-type glycans |
| |
Authors: | Vishwanath B Chachadi Shashikala R Inamdar Lu-Gang Yu Jonathan M Rhodes Bale M Swamy |
| |
Institution: | (1) P.G. Department of Studies in Biochemistry, Karnatak University, Dharwad, 580 003, India;(2) The Henry Wellcome Laboratory of Medicine and cellular gastroenterology, School of Clinical Sciences, University of Liverpool, Liverpool, L69 3BX, UK; |
| |
Abstract: | Sclerotium rolfsii lectin (SRL), a secretory protein from the soil borne phytopathogenic fungus Sclerotium rolfsii, has shown in our previous studies to bind strongly to the oncofetal Thomson-Friedenreich carbohydrate (Galβ1-3GalNAc-ser/thr,
T or TF) antigen. TF antigen is widely expressed in many types of human cancers and the strong binding of SRL toward such
a cancer-associated carbohydrate structure led us to characterize the carbohydrate binding specificity of SRL. Glycan array
analysis, which included 285 glycans, shows exclusive binding of SRL to the O-linked mucin type but not N-linked glycans and
amongst the mucin type O-glycans, lectin recognizes only mucin core 1, core 2 and weakly core 8 but not to other mucin core
structures. It binds with high specificity to “α-anomers” but not the “β-anomers” of the TF structure. The axial C4-OH group
of GalNAc and C2-OH group of Gal is both essential for SRL interaction with TF disaccharide, and substitution on C3 of galactose
by sulfate or sialic acid or N-acetylglucosamine, significantly enhances the avidity of the lectin. SRL differs in its binding to TF structures compared
to other known TF-binding lectins such as the Arachis hypogea (peanut) agglutinin, Agaricus bisporus (mushroom) lectin, Jackfruit, Artocarpus integrifolia (jacalin) and Amaranthus caudatus (Amaranthin) lectin. Thus, SRL has unique carbohydrate-binding specificity toward TF-related O-linked carbohydrate structures.
Such a binding specificity will make this lectin a very useful tool in future structural as well as functional analysis of
the cellular glycans in cancer studies. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|