Identification of novel HXT genes in Saccharomyces cerevisiae reveals the impact of individual hexose transporters on qlycolytic flux

摘要: Summary In Saccharomyces cerevisiae, hexose uptake is mediated by HXT proteins which belong to a superfamily of monosaccharide facilitators. We have identified three more genes that encode transporters (HXT5, 6, 7). Genes HXT6 and HXT7 are almost identical located in tandem 3′ adjacent HXT3 on chromosome IV. constructed set congenic strains expressing none or any one the seven known followed growth flux rates for glucose utilization. The hxt null strain does not grow glucose, fructose mannose, both rate were below detection level. Expression either HXT1, 2, 3, 4, 6 7 basically sufficient aerobic these sugars. In most constructs, was preferred substrate compared mannose. There considerable variation with 1% dependent expression individual genes. HXT2, background 0.1% while only 3 4 requires higher (≥1%) concentrations. These results demonstrate can function independently as transporters, metabolically relevant from S. cerevisiae been identified.