Low auxotrophy-complementing amino acid concentrations reduce yeast chronological life span

• Type: Article in International Scientific Journal
• Date: 2007

Authors

Pedro Gomes (Author) Other; Sampaio Marques, B (Author) Other; Ludovico, P (Author) Other; Rodrigues, F (Author) Other; Leao, C (Author) Other

Journal

Title: Mechanisms of Ageing and Development

Vol. 128

Pages: 383-391

ISSN: 0047-6374

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 29 Citations

Scopus - 36 Citations

Other information

Authenticus ID: P-004-AE4

DOI: 10.1016/j.mad.2007.04.003

Abstract (EN): In the yeast Saccharomyces cerevisiae, interventions resembling caloric restriction, either by reduction of glucose or non-essential amino acid content in the medium, prolong life span and retard aging. Here we have examined the role of auxotrophy-complementing amino acid supplementation of S. cerevisiae strains in determining yeast chronological life span and stress resistance. The results obtained from cells cultured in standard amino acid concentrations revealed a reduced final biomass yield and premature aging phenotypes. These included shorter life span and indicators of oxidative stress, together with a G2/M cell cycle arrest and the appearance of a sub-G0/G1 population pointing to the occurrence of a specific cell death programme under starvation of essential amino acids. In order to overcome this starvation, five times higher amino acid concentrations were supplied to the medium as has already been commonly used by few laboratories. Such cultures reached more than five-fold higher final biomass yield in stationary phase and the early aging phenotypes were abrogated. Furthermore, in a long-lived yeast strain lacking TOR1, there was no positive effect of amino acid supplementation on longevity. On the contrary, amino acid supply had a positive effect on chronological life span of RAS2 deleted cells. This study may provide novel insights into the role of essential nutrients and their effect on aging process and raises the warning that the positive effects of caloric restriction on life span maybe restricted to non-essential nutrients. Moreover, the severe consequences on cell physiology, life span and stress resistance induced by essential amino acid imbalances presents a note of caution for those still using standard amino acid concentrations for studies with auxotrophic yeast strains.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9