Inactivity of glycyl-glycyl-arginine and two putative (QSAR) peptide analogues of barnacle waterborne settlement pheromone

Abstract

The effect of two putative tripeptide analogues (isoleucine-isoleucine-arginine [IIR] and valine-leucine-arginine [VLR]) and a reported analogue, glycyl-glycyl-arginine (GGR), of the waterborne cue to settlement of Balanus amphitrite amphitrite Darwin cypris larvae has been investigated. Settlement in the presence of these tripeptides was not significantly different from that in filtered seawater. Because crude waterborne cue and settlement-inducing protein complex both significantly evoked settlement, the cyprids used in this study were competent to respond. The overall results, therefore, demonstrate that IIR, VLR and GGR are not analogues of barnacle waterborne settlement pheromone.