Possible mechanism for the inhibition of lectin-erythrocyte interaction in presence of endogenous lectin receptor.
The presence of hydrophobic sites in the lectin-I molecule was indicated by hydrophobic probes like 1-anilinonapthalene-8-sulfonic acid (ANS), 2-p-toluidinyl napthalene-6-sulfonic acid (TNS). N-phenyl-1-napthylamine (NA) and rose bengal (RB). This was further confirmed by amino acid modifications in the hydrophobic region of the lectin-I molecule. The binding of ANS, TNS, NA and RB to lectin-I was affected in the presence of NaCl. The involvement of hydrophobic interactions in rice-bean lectin-I-endogenous lectin receptor (ELR) complex were indicated by alterations in the circular dichroism and fluorescence emission spectra. The percentage of beta-conformation (55-63%) of lectin-I was decreased by addition of ELR. ELR on reacting with lectin-I reduced the fluorescence emissions of the hydrophobic probes while fluorescence emission of ANS, TNS, NA and RB were greatly enhanced in presence of lectin-I alone. N-aceyl-galactosamine did not change the fluorescence emissions of any of the hydrophobic probes in presence or in absence of lectin-I. This demonstrates that carbohydrate and hydrophobic sites may be different and non-interacting. It is proposed that the ELR in reacting with lectin-I, induced conformational changes in the lectin-I molecule and thereby affected its erythroagglutinating activity with human blood group "A" erythrocytes.
Basu
P S
PS
Indian Institute of Chemical Biology 4, Calcutta, India.
Datta
P K
PK
Datta
T K
TK
D015057:1-Naphthylamine / Q000031:analogs & derivatives / Q000378:metabolism; D015077:2-Hydroxy-5-nitrobenzyl Bromide / Q000378:metabolism; D000116:Acetylgalactosamine / Q000378:metabolism; D000817:Anilino Naphthalenesulfonates / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism*; D037161:Galectins; D006801:Humans; D037102:Lectins / Q000378:metabolism*; D009282:Naphthalenesulfonates / Q000378:metabolism; D011975:Receptors, Mitogen / Q000378:metabolism*; D012395:Rose Bengal / Q000378:metabolism
D000817:Anilino Naphthalenesulfonates; D037161:Galectins; D037102:Lectins; D009282:Naphthalenesulfonates; D011975:Receptors, Mitogen; C081157:lectin-1, Geodia cydonium; D012395:Rose Bengal; C027132:1-anilino-8-naphthalenesulfonate; D015077:2-Hydroxy-5-nitrobenzyl Bromide; C009497:2-(4-toluidino)-6-naphthalenesulfonic acid; C005444:N-phenyl-1-naphthylamine; D015057:1-Naphthylamine; D000116:Acetylgalactosamine