The hypertrehalosaemic peptides of cockroaches: a phylogenetic study.

Hypertrehalosaemic peptides from the corpora cardiaca of 14 different species were compared with respect to phylogenetic relationships within the insect suborder Blattaria (cockroaches). Gland extracts from members of the family Blattidae (Periplaneta americana, P. brunnea, P. australasiae, P. fuliginosa, and Blatta orientalis) contain two hypertrehalosaemic octapeptides with identical properties to the recently sequenced peptides M I and M II from the American cockroach, whereas corpora cardiaca from members of the families Blaberidae and Blattellidae (Nauphoeta cinerea, Leucophaea maderae, Blaberus discoidalis, B. trapezoideus, Diploptera punctata, and Gromphadorhina portentosa) possess one hypertrehalosaemic decapeptide with identical properties as the peptide recently sequenced from B. discoidalis and N. cinerea. A member of the family of Polyphagidae (Polyphaga aegyptiaca), placed at the origin of the phyletic tree of Blattaria, has two hypertrehalosaemic factors in its corpus cardiacum which are each different from M I, M II, and HTH.