The free amino acids of the ageing female Aedes aegypti mosquito

Abstract Quantitative chromatographic methods were used to compare the free amino acid patterns of tissue extracts of ageing female Aedes aegypti mosquitoes maintained on three different dietary regimens. Alanine, arginine, glutamic acid, glutamine, glycine, histidine, leucine and/or iso leucine, phenylalanine, proline, serine, taurine, threonine, tryptophan, and valine were consistently present in the tissue extracts. Of these alanine, histidine, arginine, glutamic acid, and lysine were present in the highest concentrations. Aspartic acid was found in only one age group, and tyrosine was found only in mosquitoes which had had a blood meal. In contrast to the mosquitoes maintained on sucrose, in which the level of methionine remained constant while glutamine and histidine decreased, the mosquitoes maintained on raisins or given blood meals showed significant increases in the levels of these three amino acids. A peptide which has been labelled X 1 in the quantitative studies was present in large quantities at the spot occupied by β-alanine in the standard chromatograms. In all three groups this peptide decreased uniformly in amount as the mosquitoes aged.