Studies on the biochemistry of insects. XVI. Various data on protein metabolism during metamorphosis of Malacoma

Abstract

We study by Lowry’s photocolorimetric method and paper electrophoresis soluble proteins and the proteic fractions which appear in the three phases of the metamorphosis of the lepi- dopterous Malacosoma neustria so as tin the excrements. Itwas found the proteins increase a lot when the larva is trans- forming to chrisalys, thus there must be a transformation from other inmetiate principies to proteids, they decrease afterwards to a third of then in the female buterfly and the figure is very low in the males after the fecundation.

These proteins are distributed in two fractions in the larva, in three in the crisalys and female butterflies and in two also as in the larves, in the males. The slow fraction of them appears in similar proportions in the larvae and the female butterflies and males and the figure is reduced to the half in the crisalys. The fast fraction prevails in the crisalys, it descreases in the female butterfly and the descrease is very strong in the larve and the males, the valúes found being approximately the same in two these latter. The intermedíate fraction in crisalys and imagine female is much higher in the former.