Biochemistry of Amino Acids - A. Majster 1961

The Role of Amino Acids in Nutrition
Amino Acid Requirements in Lower Animals

The amino acid requirements have been investigated in only a few species of Protozoa and invertebrates; the relevant data are given in Table 10. Trichomonas foetus requires the Ten Amino Acids that are essential for the rat, as well as Glycine, Proline, and Serine. However, maximum growth is not achieved in this medium; it is possible that Peptides are the missing factors [13]. The requirements of Tetrahymena geleii are similar, except that this Organism does not require glycine, and The Need for serine was observed in only one of the two studied strains [14–16]. Similarly to what has been observed in higher animals, Tyrosine exerts a sparing effect on the phenylalanine requirement, cystine and homocysteine on the Methionine requirement, and citrulline and Ornithine on the Arginine requirement. The confused flour beetle, Tribolium confusum, requires the same set of Amino acids as the rat [17]. Similar results were obtained with Anthrenus scrofulariae [16]. The requirements of the mosquito larvae Aedes aegypti [18] have not yet been fully elucidated; a requirement for valine was not established, and neither phenylalanine nor tyrosine proved to be essential, although the simultaneous omission of both amino acids resulted in growth arrest. In general, the amino acid requirements of lower organisms, on the one hand, and of the rat, dog, chicken, mouse, and human, on the other, are strikingly similar. As Table 10 shows, there are eight "major" amino acids required by all these animal species.