INVESTIGADORES
GONZALEZ FLORES melisa
congresos y reuniones científicas
Título:
Convergent adaptation of S. uvarum to sulphite resistance
Autor/es:
GUTIERREZ MACIAS LAURA; PEREZ TORRADO ROBERTO; GONZALEZ FLORES MELISA; ADAM A.C.; RODRIGUEZ MARIA EUGENIA; LOPES CHRISTIAN ARIEL; QUEROL AMPARO; BARRIO ELADIO
Lugar:
Heidelberg
Reunión:
Workshop; EMBO Workshop: Experimental Approaches to Evolution and Ecology Using Yeast and Other Model Systems; 2018
Institución organizadora:
EMBO Workshop: Experimental Approaches to Evolution and Ecology Using Yeast and Other Model Systems
Resumen:
Four subpopulations of S. uvarum have been reported: Holartic and South America-A (SA-A) detected in both natural and fermentative environments and Australasian and South America-B (SA-B) only detected in natural environments. However, little is known about the phenotypic differences associated with either their phylogenetic origin or their ecological adaptions. We studied the response of 61 strains of S. uvarum included in three subpopulations (Holartic, SA-A and SA-B) to the following stress conditions: temperature (13ºC to 30°C), ethanol (0 to 8% v/v) and nitrogen concentrations (20 to 300mg/L YAN) using microplate assays. The Holartic strains exhibited the greatest plasticity (ability to modify their performance in different conditions), being also the most cryotolerant. Regarding ethanol tolerance, very low plasticity was detected in populations from natural environments (independently from their genetic history), showing the lowest ethanol tolerance. Finally, strains from fermentative environments showed the highest nitrogen requirement. One strain representing each subpopulation was selected for competition assays in extreme conditions of temperature (13°C and 25°C), ethanol (0 and 8%v/v) and YAN (40 and 300 mg/L). The implantation capacity was evaluated by mtDNA-RFLP analysis. In extreme conditions (either 8% ethanol or 13ºC), a significant implantation of the Holartic strain (more than 55%), versus SA-A (aprox. 25%) and SA-B (aprox. 20%) was observed. Either at 0% ethanol or at 25°C, the three strains were detected in equal proportions. At 40mg/L YAN, South American strains (both SA-A and SA-B) dominated over the Holartic strain (50% and 35% vs 15%, respectively). The SA-B strain was not able to grow at high YAN concentrations while the remaining strains showed similar implantation percentages. We evidenced different physiological adaptive mechanisms in S. uvarum that could be associated to its domestication, as well as a putative explanation about the absence of SA-B subpopulation in fermentative processes.