The effect of mono‐amino acids on larval settlement of the barnacle, Balanus amphitrite Darwin

Settlement of barnacle larvae is believed to be induced by the chemical cues present in their surrounding environment. Here, an investigation was carried out on the effects of sixteen different mono‐amino acids with acidic, basic, uncharged polar and nonpolar side chains, and GABA on larval settlement of the barnacle, Balanus amphitrite. Settlement inducing activity by nine mono‐amino acids, viz. asparagine, glutamine, tyrosine, serine, glycine, tryptophan, leucine, isoleucine and valine (but not phenylalanine) with uncharged polar and nonpolar side chains was observed. Of these, the most active mono‐amino acids were serine, leucine and isoleucine, which were effective at a threshhold of 1.0 × 10^‐7 M. On the other hand, aspartic acid, glutamic acid, GABA, and the basic mono‐amino acids lysine, arginine and histidine did not have any inducing effect. These results suggest that uncharged polar and non‐polar end group of the amino acid chain play an important role in inducing the settlement process in cyprids.

Key words:

• settlement
• cyprid
• mono‐amino acids
• Balanus amphitrite

Notes

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