Effect of halogenated pyrimidine 5′-mononucleotides on dTMP-permeable yeast strains and the isolation and characterization of resistant mutants

Seven dominant mutations showing greatly enhanced resistance to the glucose repression of galactokinase synthesis have been isolated from GAL81 mutants, which have the constitutive phenotype but are still strongly repressible by glucose for the synthesis of the Leloir enzymes. These glucose-resistant mutants were due to semidominant mutations at either of two loci, GAL82 and GAL83. Both loci are unlinked to the GAL81- gal4, gal80, or gal7 X gal10 X gal1 locus or to each other. The GAL83 locus was mapped on chromosome V at a site between arg9 and cho1. The GAL82 and GAL83 mutations produced partial resistance of galactokinase to glucose repression only when one or both of these mutations were combined with a GAL81 or a gal80 mutation. The GAL82 and GAL83 mutations are probably specific for expression of the Leloir pathway and related enzymes, because they do not affect the synthesis of alpha-D-glucosidase, invertase, or isocitrate lyase.

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Isolation and characterization of valine-resistant mutants of Nicotiana plumbaginifolia

Theoretical and Applied Genetics ◽

10.1007/bf00303963 ◽

1988 ◽

Vol 75 (2) ◽

pp. 272-277 ◽

Cited By ~ 11

Author(s):

A. Marion-Poll ◽

C. Missonier ◽

J. Goujaud ◽

M. Caboche

Keyword(s):

Nicotiana Plumbaginifolia ◽

Isolation And Characterization ◽

Resistant Mutants

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Transposon mutagenesis ofClostridium acetobutylicumP262: isolation and characterization of solvent deficient and metronidazole resistant mutants

FEMS Microbiology Letters ◽

10.1111/j.1574-6968.1993.tb06596.x ◽

1993 ◽

Vol 114 (3) ◽

pp. 343-348 ◽

Cited By ~ 12

Author(s):

Brendan L. Babb ◽

Helen J. Collett ◽

Sharon J. Reid ◽

David R. Woods

Keyword(s):

Transposon Mutagenesis ◽

Isolation And Characterization ◽

Resistant Mutants

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Isolation and characterization of hydrocarbon-degrading and biosurfactant-producing yeast strains obtained from a polluted lagoon water

World Journal of Microbiology and Biotechnology ◽

10.1007/s11274-008-9778-3 ◽

2008 ◽

Vol 24 (11) ◽

pp. 2539-2545 ◽

Cited By ~ 37

Author(s):

Matthew O. Ilori ◽

Sunday A. Adebusoye ◽

Adedoyin C. Ojo

Keyword(s):

Lagoon Water ◽

Isolation And Characterization ◽

Yeast Strains

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Isolation and Characterization of Live Yeast Cells from Ancient Vessels as a Tool in Bio-Archaeology

mBio ◽

10.1128/mbio.00388-19 ◽

2019 ◽

Vol 10 (2) ◽

Cited By ~ 10

Author(s):

Tzemach Aouizerat ◽

Itai Gutman ◽

Yitzhak Paz ◽

Aren M. Maeir ◽

Yuval Gadot ◽

...

Keyword(s):

Ancient Dna ◽

Residue Analysis ◽

Fermented Food ◽

Yeast Cells ◽

Fermented Beverages ◽

Isolation And Characterization ◽

Yeast Strains ◽

Novel Approach ◽

Clay Matrix

ABSTRACTAncient fermented food has been studied based on recipes, residue analysis, and ancient-DNA techniques and reconstructed using modern domesticated yeast. Here, we present a novel approach based on our hypothesis that enriched yeast populations in fermented beverages could have become the dominant species in storage vessels and their descendants could be isolated and studied today. We developed a pipeline of yeast isolation from clay vessels and screened for yeast cells in beverage-related and non-beverage-related ancient vessels and sediments from several archaeological sites. We found that yeast cells could be successfully isolated specifically from clay containers of fermented beverages. The findings that genotypically the isolated yeasts are similar to those found in traditional African beverages and phenotypically they grow similar to modern beer-producing yeast strongly suggest that they are descendants of the original fermenting yeast. These results demonstrate that modern microorganisms can serve as a new tool in bio-archaeology research.IMPORTANCESo far, most of the study of ancient organisms has been based mainly on the analysis of ancient DNA. Here we show that it is possible to isolate and study microorganisms—yeast in this case—from ancient pottery vessels used for fermentation. We demonstrate that it is highly likely that these cells are descendants of the original yeast strains that participated in the fermentation process and were absorbed into the clay matrix of the pottery vessels. Moreover, we characterized the isolated yeast strains, their genomes, and the beer they produced. These results open new and exciting avenues in the study of domesticated microorganisms and contribute significantly to the fields of bio- and experimental archaeology that aim to reconstruct ancient artifacts and products.

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