Ah. Undeen et Lf. Solter, SUGAR ACQUISITION DURING THE DEVELOPMENT OF MICROSPORIDIAN (MICROSPORA, NOSEMATIDAE) SPORES, Journal of invertebrate pathology, 70(2), 1997, pp. 106-112
Helicoverpa tea larvae were infected with Vairimorpha necatrix. The fa
t body was triturated and sporulation stages were fractionated accordi
ng to buoyant density by Ludox density gradient centrifugation, Spores
and sporulation stages formed two minor bands with buoyant densities
of 1.072 and 1.121 g/ml, and two major bands with buoyant densities of
1.150 and 1.198 g/ml. The higher bands of less dense sporoblastic sta
ges first appeared 96 hr following infection and the band containing t
he heaviest (1.198 g/ml) and most refringent mature spores appeared la
st, ca. 24 hr after the appearance of the other bands, Although the ba
nds remained in the same relative positions regardless of the time aft
er inoculation, the percentage of spores in Band 4 increased with time
. The concentration of sugar in the spores from the 1.198-g/ml band wa
s more than four times the concentration found in spores in the 1.150-
g/ml band and accounted for more than 60% of the increase in spore wei
ght between the two density classes. Similar tests with Nosema algerae
yielded similar results, with sugars accounting for 88% of the increa
sed spore weight. Sugar acquisition appears to occur during the attain
ment of the final spore density and perhaps signals spore maturation.
(C) 1997 Academic Press.