Sugar transport systems in Kluyveromyces marxianus CCT 7735

• Autor(a) principal: Silveira, Fernando Augusto da
• Data de Publicação: 2019
• Outros Autores: Diniz, Raphael Hermano S., Silveira, Wendel B. da, Sampaio, Geraldo M. S., Brandão, Rogelio L., Castro, Ieso M.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: https://doi.org/10.1007/s10482-018-1143-4; http://www.locus.ufv.br/handle/123456789/24032
• topic: Glucose; Repression; K marxianus; Lactose; Metabolism regulation; Sugar uptake

The pattern of glucose repression in most Kluyveromyces marxianus strains does not correlate with fermentative behaviour; however, glucose repression and fermentative metabolism appear to be linked to the kinetics of sugar uptake. In this work, we show that lactose transport in K. marxianus CCT 7735 by lactose-grown cells is mediated by a low-affinity H+-sugar symporter. This system is glucose repressed and able to transport galactose with low affinity. We also observed the activity of a distinct lactose transporter in response to raffinose. Regarding glucose uptake, specificities of at least three low-affinity systems rely on the carbon source available in a given growth medium. Interestingly, it was observed only one high-affinity system is able to transport both glucose and galactose. We also showed that K. marxianus CCT 7735 regulates the expression of sugar transport systems in response to glucose availability.