The contribution of electrostatic forces to the process of adherence of Candida albicans yeast cells to substrates

Abstract Thermoanaerobacter thermohydrosulfuricus Rt8.B1 catabolized xylose by the pentose phosphate pathway, and xylose isomerase and xylulokinase were inducible. The uptake of xylose was by two low-affinity, inducible systems. Both systems were resistant to the protonophore, tetrachlorosalicylanilide, the F₁F₀-ATPase inhibitor, N , N -dicyclohexylcarboiimide, and the sodium/proton antiporter, monensin. The high capacity system (100 nmol min⁻¹ (mg protein)⁻¹) was only expressed when the bacterium was grown with a high concentration of xylose (50 mM). It took more than 60 mM xylose to saturate the high capacity system. When T. thermohydrosulfuricus was grown with a low concentration of xylose (5 mM), xylose uptake was saturated by as little as 10 mM xylose (18 nmol min⁻¹ (mg protein)⁻¹). Cells grown with 50 mM xylose could not transport glucose, and high capacity xylose transport was not inhibited by glucose or non-metabolizable glucose analogues. Cells grown with 5 mM xylose transported glucose at a rapid rate (30 nmol min⁻¹ (mg protein)⁻¹), and low capacity xylose uptake was competitively inhibited by either glucose or 2-deoxy-glucose. Because the glucose uptake of cells grown on 5 mM xylose was competitively inhibited by xylose, it appeared that the low capacity xylose uptake system was a glucose/xylose carrier.