Metalloproteases and egg-hatching in Pediculus humanus, the body (clothes) louse of humans (Phthiraptera: Insecta)

Abstract

To investigate the biochemical components of egg-hatch in the body louse, Pediculus humanus, egg-shell-washings (ESW) were collected during the first 2 h post-hatching and analysed by gelatin SDS-PAGE. These ESW contained proteases with molecular mass in the range of 25-100 kDa; the most abundant proteases were ∼25 kDa. The 3 main regions of protease activity in the one-dimensional gelatin SDS-PAGE gels resolved to at least 23 distinct regions of protease activity when analysed by two-dimensional gelatin SDS-PAGE, with iso-electric points spread over the entire 3 to 10 pH range. Mechanistic characterization indicated that the ESW contained proteases of the metallo-class, inhibited by both 1,..