M. Nalini et al., CHARACTERIZATION OF A NATURAL HEMAGGLUTININ IN THE SERUM OF A FRESH-WATER CRAB PARATHELPHUSA-HYDRODROMUS (HERBST), ARCH I PHYS, 102(5), 1994, pp. 259-264
Citations number
48
Categorie Soggetti
Physiology,Biology,Biophysics
Journal title
Archives internationales de physiologie, de biochimie et de biophysique
A naturally occurring hemagglutinin (HA) was detected in the serum of
the freshwater crab Parathelphusa hydrodromus using mammalian erythroc
ytes (RBC) as indicator cells. The serum gave the highest HA titer wit
h rabbit RBC. In cross adsorption tests, this RBC type completely adso
rbed all HA activities from serum. An analysis of the physico-chemical
properties of HA showed it to be specifically dependent on the presen
ce of Ca2+ for its activity, irreversibly sensitive to EDTA, stable be
tween pH 7.5 and 10.0, and heat-labile. Further studies demonstrated t
hat the HA is proteinaceous as it was precipitable by conventional dep
roteinizing agents, and susceptible to the action of proteases and 2-m
ercaptoethanol. HA-inhibition assays performed with 44 carbohydrates r
evealed that the serum HA was specific for non-reducing terminal gluco
se with alpha 1-2 glycosidic linkage. Thus this agglutinin appears to
be unique among all the known crustacean agglutinins.