Changes in plasma membrane fluidity lower the sensitivity ofS. cerevisiae to killer toxin K1

Flegelová, H.; Chaloupka, Roman; Novotná, Drahomíra; Maláč, J.; Gášková, Dana; Sigler, Karel; Janderová, B.

doi:10.1007/bf02931510

Cited by 6 publications

(2 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Killer activity has been observed in numerous genera of wine yeasts, such as Saccharomyces, Candida, Cryptococcus, Debaryomyces, Hanseniaspora, Kluyveromyces, Pichia, Williopsis and Zygosaccharomyces (Zagorc et al, 2001). Several papers have been published about killer toxins (Flagelova et al, 2003;Yap et al, 2000). No killer activity, investigated according to Zagorc et al (2001) has been detected in the present study (data not shown).…”

Section: Dominance Resultscontrasting

confidence: 56%

Investigation of the dominance behavior of Saccharomyces cerevisiae strains during wine fermentation

Perrone

Giacosa

Cocolin

et al. 2013

International Journal of Food Microbiology

View full text Add to dashboard Cite

During wine fermentation, different strains of Saccharomyces cerevisiae compete in the same fermenting must and dominance takes place when one strain overcomes all the others. The purpose of this study was to investigate this phenomenon by identifying S. cerevisiae strains endowed with this feature and to test them in laboratory fermentations. First, autochthonous S. cerevisiae from Nebbiolo fermentations were isolated, molecularly identified and characterized. Genetically diverse S. cerevisiae strains were subsequently subjected to physiological characterization and to microscale fermentation, the weight loss kinetics was measured and HPLC analysis was performed at the end of the fermentation. Then, the strains that presented good fermentation characteristics were chosen for further analysis and to determine the dominance feature. For this purpose, couples of strains were co-inoculated in Nebbiolo must and the fermentations were monitored by microbiological and chemical analysis. Two different inoculation approaches were used: cofermentations in flasks with mixed cells and reactor co-fermentations, in which the cells from the two different strains were kept separate by means of a 0.45 µm filter membrane, which allowed the fermenting must to move freely between the two compartments. During the flask co-fermentations, a minisatellite PCR protocol was applied, in order to differentiate the two strains and determine which one was able to dominate. The protocol included a culture-dependent approach and an independent one. In the first case, DNA extraction was performed on all the colonies scraped off the plates after sampling. In the second case, DNA extraction was performed directly on the fermenting must. The strains that were able to dominate were tested against several S. cerevisiae in order to confirm this dominance behavior. Dominance was observed in the early stages of fermentation, as early as 3 days. Combinations of dominant and not-dominant strains were subjected to further tests in a co-fermentation reactor system, in order to perform single-strain analysis so as to obtain a better understanding of the dominance behavior. Surprisingly, the results obtained in the flask cofermentations were not confirmed. In fact, the two strains, one which was hypothesized to be dominant and the other not-dominant, coexisted throughout the fermentation period. The results of 4 this study suggest that the dominant behavior of S. cerevisiae is only expressed when they sense other yeasts in the same environment.

show abstract

Section: Dominance Resultscontrasting

confidence: 56%

Investigation of the dominance behavior of Saccharomyces cerevisiae strains during wine fermentation

Perrone

Giacosa

Cocolin

et al. 2013

International Journal of Food Microbiology

View full text Add to dashboard Cite

show abstract

“…After reaching the cytoplasmic membrane certain killer toxins, such as the K1 toxin produced by S. cerevisiae , exert its lethal activity by ion channel formation and therefore, perturbing the permeability of the membrane (Flegelová et al, 2003 ). Similarly, the killer toxin from P. membranifaciens PMKT has been suggested to bind to a receptor in the cell wall such as β-D-(1,6)-glucan that would somehow allow crossing the cell wall and binding to a second receptor in the plasma membrane (Santos et al, 2005 ; Santos and Marquina, 2011 ).…”

Section: Discussionmentioning

confidence: 99%

Non-canonical Activities of Hog1 Control Sensitivity of Candida albicans to Killer Toxins From Debaryomyces hansenii

Morales-Menchén

Navarro‐García

Guirao-Abad

et al. 2018

Front. Cell. Infect. Microbiol.

View full text Add to dashboard Cite

Certain yeasts secrete peptides known as killer toxins or mycocins with a deleterious effect on sensitive yeasts or filamentous fungi, a common phenomenon in environmental species. In a recent work, different Debaryomyces hansenii (Dh) strains isolated from a wide variety of cheeses were identified as producing killer toxins active against Candida albicans and Candida tropicalis. We have analyzed the killer activity of these toxins in C. albicans mutants defective in MAPK signaling pathways and found that the lack of the MAPK Hog1 (but not Cek1 or Mkc1) renders cells hypersensitive to Dh mycocins while mutants lacking other upstream elements of the pathway behave as the wild type strain. Point mutations in the phosphorylation site (T174A-176F) or in the kinase domain (K52R) of HOG1 gene showed that both activities were relevant for the survival of C. albicans to Dh killer toxins. Moreover, Hog1 phosphorylation was also required to sense and adapt to osmotic and oxidative stress while the kinase activity was somehow dispensable. Although the addition of supernatant from the killer toxin- producing D. hansenii 242 strain (Dh-242) induced a slight intracellular increase in Reactive Oxygen Species (ROS), overexpression of cytosolic catalase did not protect C. albicans against this mycocin. This supernatant induced an increase in intracellular glycerol concentration suggesting that this toxin triggers an osmotic stress. We also provide evidence of a correlation between sensitivity to Dh-242 killer toxin and resistance to Congo red, suggesting cell wall specific alterations in sensitive strains.

show abstract

Current awareness on yeast

2004

Yeast

View full text Add to dashboard Cite

In order to keep subscribers up‐to‐date with the latest developments in their field, this current awareness service is provided by John Wiley & Sons and contains newly‐published material on yeasts. Each bibliography is divided into 10 sections. 1 Books, Reviews & Symposia; 2 General; 3 Biochemistry; 4 Biotechnology; 5 Cell Biology; 6 Gene Expression; 7 Genetics; 8 Physiology; 9 Medical Mycology; 10 Recombinant DNA Technology. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. (4 weeks journals ‐ search completed 19th. May. 2004)

show abstract

Changes in plasma membrane fluidity lower the sensitivity ofS. cerevisiae to killer toxin K1

Cited by 6 publications

References 22 publications

Investigation of the dominance behavior of Saccharomyces cerevisiae strains during wine fermentation

Investigation of the dominance behavior of Saccharomyces cerevisiae strains during wine fermentation

Non-canonical Activities of Hog1 Control Sensitivity of Candida albicans to Killer Toxins From Debaryomyces hansenii

Current awareness on yeast

Contact Info

Product

Resources

About