O efeito da complexidade estrutural da fonte de nitrogênio no transporte de amônio em Saccharomyces cerevisiae
Main Article Content
Abstract
O estudo do efeito da complexidade estrutural da fonte de nitrogênio no transporte de amônio em Saccharomyces cerevisiae foi realizado cultivando-se o microrganismo em um meio mínimo contendo glicose e fontes de nitrogênio, variando de um simples sal de amônio (sulfato de amônio) a aminoácidos livres (casaminoácidos) e peptídeos (peptona). O transporte de amônio foi avaliado acompanhando-se a entrada do análogo metilamônio, utilizando duas metodologias diferentes: transporte de metilamônio radioativo e efluxo de potássio acoplado ao transporte de metilamônio em células crescidas em diferentes condições de cultivo. A cinética de transporte de amônio é detectada nos meios contendo peptona e amônio e não no meio suplementado com casaminoácidos, e o transporte medido em diferentes fases de crescimento sugere que o processo é mais estável em células crescidas em peptona. Os resultados descritos neste trabalho indicam que a complexidade estrutural interfere com a expressão do transportador do íon amônio e que a complementação do meio de cultura com uma fonte de nitrogênio na forma de peptídeos é a mais eficiente não só para a expressão do transportador de amônio, mas também de conferir maior estabilidade ao processo.
Metrics
Article Details
![Creative Commons License](http://i.creativecommons.org/l/by/4.0/88x31.png)
This work is licensed under a Creative Commons Attribution 4.0 International License.
The corresponding author transfers the copyright of the submitted manuscript and all its versions to Eclet. Quim., after having the consent of all authors, which ceases if the manuscript is rejected or withdrawn during the review process.
When a published manuscript in EQJ is also published in other journal, it will be immediately withdrawn from EQ and the authors informed of the Editor decision.
Self-archive to institutional, thematic repositories or personal webpage is permitted just after publication. The articles published by Eclet. Quim. are licensed under the Creative Commons Attribution 4.0 International License.
References
ALAGRAMAM, K.; NAIDER, F.; BECKER, J.M. A recognition component of the ubiquitin system is required for peptide transport in Saccharomyces cerevisiae. Mol. Microbiol., v.15, n.2, p. 225-34, 1995. [ Links ]
ANDRÉ, B. An overview of membrane transport proteins in Saccharomyces cerevisiae. Yeast, v.11, p. 1575-611, 1996. [ Links ]
BARNES, D.; LAI, W.; BRESLAV, M.; NAIDER, F.; BECKER, J.M. PTR3, a novel gene mediating amino acid-inducible regulation of peptide transport in Saccharomyces cerevisiae. Mol. Microbiol., v.29, n.1, p. 297-310, 1998. [ Links ]
COOPER, T.G. Nitrogen metabolism in Saccharomyces cerevisiae. In: STRATHERN, J.N., JONES, E.W., BROACH, J.R. The molecular biology of the yeast Saccharomyces: metabolism and gene expression. New York: Cold Spring Harbor Laboratory Press, 1992. [ Links ]
DUBOIS, E.; GRENSON, M. Methylamine/ammonia uptake systems in Saccharomyces cerevisiae: multiplicity and regulation. Mol. Gen. Genet., v.175, p. 67-76, 1979. [ Links ]
FARREL, R.E.; GERMIDA, J.J.; MING HUANG, P. Effects of chemical speciation in growth media on the toxicity of mercury(II). Appl. Environ. Microbiol., v.59, n.2, p. 1507-14, 1993. [ Links ]
FLORES, C.L.; RODRIGUEZ, C.; PETIT, T.; GANCEDO, C. Carbohydrate and energy-yielding metabolism in non-conventional yeasts. FEMS Microbiol. Rev., v.24, p. 507-29, 2000. [ Links ]
HORÁK, J. Yeast nutrient transporters. Biochim. Biophys. Acta, v.1331, p. 41-79, 1997. [ Links ]
IRAQUI, I.; VISSERS, S.; BERNARD, F.; DE CRAENE, J-O.; BOLES, E.; URRESTARAZU, A.; ANDRÉ, B. Amino acid signaling in Saccharomyces cerevisiae: a permease-like sensor of external amino acids and F-box protein GRR1p are required for transcriptional induction of the AGP1 gene, which encodes a broad-specificity amino acid permease. Mol. Cell. Biol., v.19, p. 989-1001, 1999. [ Links ]
ISLAND, M.D.; PERRY, J.R.; NAIDER, F.; BECKER, J.M. Isolation and characterization of Saccharomyces cerevisiae mutants deficient in amino acid-inducible peptide transport. Curr. Genet., v.20, p. 457-63, 1991. [ Links ]
JANIAUX, J.C.; GRENSON, M. GAP1, the general amino acid permease gene of Saccharomyces cerevisiae. Nucleotide sequence, protein similarity with other bakers yeast amino acid permeases and nitrogen catabolite repression. Eur. J. Biochem., v.190, p. 39-44, 1990. [ Links ]
LARGE, P. Degradation of organic nitrogen compounds by yeasts. Yeast, v.2,p. 1-34, 1986. [ Links ]
LEAO, C. Toxicidade do etanol e outros alcanóis para a levedura Saccharomyces cerevisiae. Alvos e mecanismos de ação. Braga, 1984. Tese (Doutorado) – Universidade do Minho. [ Links ]
MAGASANIK, B. Regulation of nitrogen utilization. In: JONES, E.W.; PRINGLE, J.R.; BROACH, J.R. The molecular and cellular biology of the yeast Saccharomyces: gene expression. New York: Cold Spring Harbor Laboratory Press, 1992. [ Links ]
MARINI, A.M.; SOUSSI-BOUDEKOU, S.; VISSERS, S.; ANDRÉ, B. A family of ammonium transporters in Saccharomyces cerevisiae. Mol. Cell. Biol., v.17, n.8, p. 4282-93, 1997. [ Links ]
PIERCE, J.S. Horace Brown Memorial Lecture: the role of nitrogen in brewing. J. Inst. Brew., v.93, p. 378-81, 1987. [ Links ]
STEINER, H.Y.; NAIDER, F.; BECKER, J.M. The PTR family: a new group of peptide transporter. Mol. Microbiol., v.16, n.5, p. 825-34, 1995. [ Links ]
STEWART, G.G.; RUSSELL, I. An introduction to brewing science & technology: brewers yeast. London: The Institute of Brewing, 1998. 108p. [ Links ]
TERSCHURE, E.G., SILLJÉ, H.H.W., RAEVEN, L.J.R.M., BOONSTRA, J., VERLEIJ, A.J., VERRIPS, C.T. Nitrogen-regulated transcription and enzyme activities in continuous cultures of Saccharomyces cerevisiae. Microbiology, v.141, p. 1101-8, 1995. [ Links ]
TERSCHURE, E.G., van RIEL, N.A.W., VERRIPS, C.T. The role of ammonia metabolism in nitrogen catabolite repression in Saccharomyces cerevisiae. FEMS Microbiol. Rev., v.24, p. 67-83, 2000. [ Links ]
THEVELEIN, J.M. Signal transduction in yeast. Yeast, v. 10, p. 1753-90, 1994. [ Links ]
WALSH, M.C.; SMITS, H.P.; SCHOLTE, M.; VANDAM, K. Affinity of glucose transport in Saccharomyces is modulated during growth in glucose. J. Bacteriol., v.176, p. 953-8, 1994. [ Links ]
WIAME, J.M.; GRENSON, M.; ARST, H.N. Nitrogen catabolite repression in yeast and filamentous fungi. Adv. Microbiol. Physiol., v.26, p. 1-35, 1985. [ Links ]