Freshly harvested cells of Penicillium crustosum Them VKM F-1746 were
more capable of excreting roquefortine than transporting it. The abili
ty to accumulate roquefortine was enhanced and the ability to excrete
was decreased by starvation in Tris-Mops, pH 6, for 1-2 days, correlat
ing with the loss of cell nitrogen. Excretion of roquefortine from the
cells of P. crustosum was energy-independent. In contrast, transport
into P. crustosum proceeded both in energy-dependent and -independent
ways by saturation mechanisms. The optimal pH of the transport was 4.5
and that of the excretion about 6-7. Copyright (C) 1996 Elsevier Scie
nce Ltd