Characterization of endopeptidases from the midgut of Morimus funereus (Coleoptera: Cerambycidae) larvae

Abstract

Application of specific chromogenic substrates, use of class-specific inhibitors, and zymogram analysis enabled us to identify several peptidase classes in extracts of the midgut of Morimus funereus larvae. Zymogram analysis with gelatin as a peptidase substrate and phenylmethylsulfonyl fluoride as an inhibitor showed that serine peptidases were the most abundant endopeptidases in the midgut of M. funereus larvae. By zymogram analysis with gelatin as a peptidase substrate and 1,10-phenanthroline as an inhibitor, metallopeptidases were also detected. Analyses of serine peptidases with specific chromogenic substrates revealed dominance of elastase-like peptidases in extracts of the midgut of M. funereus larvae, with less pronounced chymotrypsin- and trypsin-like activities.

Primenom specifičnih hromogenih supstrata, klasno-specifičnih inhibitora i zimogramske analize identifikovano je nekoliko klasa peptidaza u sirovom ekstraktu srednjeg creva larvi koleoptere Morimus funereus. Zimogramskom analizom sa želatinom kao supstratom i fenilmetilsulfonil-fluoridom kao inhibitorom utvrđeno je da su serin-peptidaze najzastupljenije peptidaze u ekstraktu srednjeg creva larvi M. funereus. Zimogramskom analizom sa želatinom kao supstratom i 1,10-fenantrolinom kaoinhibitorom takođe su detektovane metalopeptidaze. Analizom serin-peptidaza, upotrebom specifičnih hromogenih supstrata, dokazano je da su dominantni elastazi-slični enzimi u sirovom ekstraktu srednjeg creva larvi M. funereus, dok su himotripsinima- i tripsinima-slični enzimi manje zastupljeni.