Absorption of Amino Acids by Yeasts From a Semi-Defined Medium Simulating Wort

Jones, Margaret; Pragnell, M. J.; Pierce, J. S.

doi:10.1002/j.2050-0416.1969.tb03243.x

Cited by 41 publications

(15 citation statements)

References 11 publications

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“…The lack of more detailed studies on the importance of peptides in the fermentation of brewing wort and wine must is due to the difficulties involved in their isolation and characterization. Several studies have been conducted in order to elucidate the importance of the amino acid spectrum and composition on yeast fermentation and beer flavor, the amino acid and peptide profile and the removal of free amino acids and peptides 5,8,17,26,[36][37][38] . Recent publications have reported on the utilization and the effect of nitrogen source and concentration on the uptake of peptides by brewing lager strains in a defined medium 26,27 .…”

Section: Discussionmentioning

confidence: 99%

“…During wort fermentation, patterns of amino acid assimilation are ordered and groups of amino acids have been identified on the basis of the rate of removal from the fer-mentation medium 28 . Wort amino acids were also classified according to the essential nature of the keto-acid analogues in yeast metabolism 17 . Brewer's wort contains a complex and large amount of peptides 26 .…”

Section: Introductionmentioning

confidence: 99%

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Altered Patterns of Maltose and Glucose Fermentation by Brewing and Wine Yeasts Influenced by the Complexity of Nitrogen Source

Batistote

Cruz

Ernandes

2006

Journal of the Institute of Brewing

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J. Inst. Brew. 112(2), 84-91, 2006Maltose and glucose fermentations by industrial brewing and wine yeasts strains were strongly affected by the structural complexity of the nitrogen source. In this study, four Saccharomyces cerevisiae strains, two brewing and two wine yeasts, were grown in a medium containing maltose or glucose supplemented with a nitrogen source varying from a single ammonium salt (ammonium sulfate) to free amino acids (casamino acids) and peptides (peptone). Diauxie was observed at low sugar concentration for brewing and wine strains, independent of nitrogen supplementation, and the type of sugar. At high sugar concentrations altered patterns of sugar fermentation were observed, and biomass accumulation and ethanol production depended on the nature of the nitrogen source and were different for brewing and wine strains. In maltose, high biomass production was observed under peptone and casamino acids for the brewing and wine strains, however efficient maltose utilization and high ethanol production was only observed in the presence of casamino acids for one brewing and one wine strain studied. Conversely, peptone and casamino acids induced higher biomass and ethanol production for the two other brewing and wine strains studied. With glucose, in general, peptone induced higher fermentation performance for all strains, and one brewing and wine strain produced the same amount of ethanol with peptone and casamino acids supplementation. Ammonium salts always induced poor yeast performance. The results described in this paper suggest that the complex nitrogen composition of the cultivation medium may create conditions resembling those responsible for inducing sluggish /stuck fermentation, and indicate that the kind and concentration of sugar, the complexity of nitrogen source and the yeast genetic background influence optimal industrial yeast fermentation performance.

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Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Altered Patterns of Maltose and Glucose Fermentation by Brewing and Wine Yeasts Influenced by the Complexity of Nitrogen Source

Batistote

Cruz

Ernandes

2006

Journal of the Institute of Brewing

View full text Add to dashboard Cite

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“…In the majority of industrial yeast fermentations a key requirement is the ability of the yeast strain to rapidly and efficiently utilise all sugars contained in the medium 21 . In order to elucidate the importance of amino acid spectrum and composition on yeast fermentation and beer flavor, the amino acid and peptide content and composition of wort and the removal of amino acids in a free and peptide form have been studied for many years 2,5,15,26,[37][38][39] . Recent publications have studied peptide utilisation and the effect of nitrogen source and concentration on the up- take of peptides by brewing lager strains in a defined medium 23,24 .…”

Section: Discussionmentioning

confidence: 99%

“…The assimilation of wort amino acids is ordered and groups of amino acids have been identified on the basis of the rate of removal from the fermentation broth 26 . Wort amino acids have also been classified according to the essential nature of the keto-acid analogues in yeast metabolism 15 . In contrast, studies on wort peptides and their uptake and influence on brewing fermentations are sparse.…”

Section: Discussionmentioning

confidence: 99%

Effect of Sugar Catabolite Repression in Correlation with the Structural Complexity of the Nitrogen Source on Yeast Growth and Fermentation

Cruz

Batistote

Ernandes

2003

Journal of the Institute of Brewing

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Biomass and ethanol production by industrial Saccharomyces cerevisiae strains were strongly affected by the structural complexity of the nitrogen source during fermentation in media containing galactose, and supplemented with a nitrogen source varying from a single ammonium salt (ammonium sulfate) to free amino acids (casamino acids) and peptides (peptone). Diauxie was observed at low galactose concentrations independent of nitrogen supplementation. At high sugar concentrations altered patterns of galactose utilisation were observed. Biomass accumulation and ethanol production depended on the nature of the nitrogen source and were different for baking and brewing ale and lager strains. Baking yeast showed improved galactose fermentation performance in the medium supplemented with casamino acids. High biomass production was observed with peptone and casamino acids for the ale brewing strain, however high ethanol production was observed only in the presence of casamino acids. Conversely, peptone was the nitrogen supplement that induced higher biomass and ethanol production for the lager brewing strain. Ammonium salts always induced poor yeast performance. The results with galactose differed from those obtained with glucose and maltose which indicated that supplementation with a nitrogen source in the peptide form (peptone) was more positive for yeast metabolism, suggesting that sugar catabolite repression has a central role in yeast performance in a medium containing nitrogen sources with differing levels of structural complexity.

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“…When ammonia was added to the sporulation medium, a difference in the nitrogen metabolism of the two strains was also observed: the glutamine pool decreased in a / a cells (as in the absence of inhibitor) but it increased slightly in a/a cells; the glutamic acid pool behaved in a similar way in both types of cells but was larger in cc/a than in a/a cells. The observation that glutamic acid did not inhibit sporulation whereas glutamine and ammonia did was not expected since glutarnic acid is the first compound of ammonia assimilation in growing cells of S. cerevisiae (Jones et al, 1969;Witt & Holzer, 1964) and is, through GS, a precursor of glutamine. Moreover, in the presence of ammonia, both the glutamine and glutamic acid pools were increased.…”

Section: D E L a V I E R -K L U T C H K Omentioning

confidence: 99%

Assimilation of Ammonia During Sporogenesis of Saccharomyces cerevisiae: Effect of Ammonia and Glutamine

et al. 1980

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~Comparison of the pools of glutamic acid and glutamine and of the specific activities of glutamine synthetase and glutamate dehydrogenases in sporulating a/cc and non-sporulating a/cc cells of Saccharomyces cerevisiae revealed a difference in their nitrogen metabolism.Glutamhe synthetase and glutamine appeared to be necessary for the sporulation process, glutamine playing, at least, a catabolic role. However, exogenous glutamine as well as ammoniainhibited sporulationwhile glutamic acid did not. Glutamine seemed to act through its amino group. Both inhibitors had at least two sites of action, one effective early in sporulation and related to DNA synthesis and the other acting later and not related to it. I N T R O D U C T I O NStarvation of the yeast Saccharomyces eerevisiae induces a differentiation process leading to meiosis and sporulation of diploid ( a / a ) cells. This process is inhibited by ammonia and some other nitrogen compounds (Miller, 1963; Piiion, 1977) but very little is known about the metabolism of ammonia in sporulating cells. In this paper, we report our studies on the activities of enzymes involved in ammonia assimilation (glutamhe synthetase, NAD-and NADP-linked glutamate dehydrogenases), the effect of the substrates of these enzymes on the sporulation process, and the variation in the sizes of pools of free glutamine and glutsmic acid during the first hours after the transfer of cells to the sporulation medium with or without ammonia. METHODS Yeast strains, growth and sporulation. Diploid cells of Saccharomyces cerevisiae 532 a / a and 533 ala,isogenic except for their mating type (Pellucuer, 19731, were used. The a / a cells were grown and allowed to sporulate as described by Durieu-Trautmann & Delavier-Klutchko (1977). The alee cells, which are unable to sporulate, were used as a control.Enzyme activities. Extracts were prepared at 4 "C by passing suspensions of cells in 100 mwpotassium phosphate buffer pH 7-8, containing 1 mhl-2-mercaptoethano1, through a French press at 100 MPa. Cell debris was removed by centrifuging for 30 min at 30000 g and the supernatant was dialysed overnight at 4 "C against buffer similar to that used for extraction.Activities of NAD-linked glutamate dehydrogenase (NAD-Gdh; EC 1 .4.1.2) and of NADP-linked glutamate dehydrogenase (NADP-Gdh; EC 1.4.1.4) were estimated by determining the rate of NADH or NADPH oxidation at 25 "C (Boehringer, 1968). The rate of reaction with NAD-Gdh was corrected by subtracting the rate of NADH oxidation observed in the absence of 2-oxoglutarate.The activity of glutamine synthetase (GS; EC 6.3.1 .2) was measured by assaying transferase activity (Woolfolk et al., 1966).Protein was determined by the Folin method of Lowry, using bovine serum albumin as standard.

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Absorption of Amino Acids by Yeasts From a Semi-Defined Medium Simulating Wort

Cited by 41 publications

References 11 publications

Altered Patterns of Maltose and Glucose Fermentation by Brewing and Wine Yeasts Influenced by the Complexity of Nitrogen Source

Altered Patterns of Maltose and Glucose Fermentation by Brewing and Wine Yeasts Influenced by the Complexity of Nitrogen Source

Effect of Sugar Catabolite Repression in Correlation with the Structural Complexity of the Nitrogen Source on Yeast Growth and Fermentation

Assimilation of Ammonia During Sporogenesis of Saccharomyces cerevisiae: Effect of Ammonia and Glutamine

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