%0 Journal Article %A Luard, Elizabeth J. %T Accumulation of Intracellular Solutes by Two Filamentous Fungi in Response to Growth at Low Steady State Osmotic Potential %D 1982 %J Microbiology, %V 128 %N 11 %P 2563-2574 %@ 1465-2080 %R https://doi.org/10.1099/00221287-128-11-2563 %I Microbiology Society, %X Glycerol and the solutes used to control the steady state osmotic potential of the medium, either glucose, glucose and fructose, or KC1, accumulated in the hyphae of Penicillium chrysogenum and Chrysosporium fastidium as the external potential was lowered. When the osmoticum was KC1, nearly all the observed hyphal osmotic potential of P. chrysogenum could be accounted for from the measured solute concentrations, but the proportion decreased when a glucose osmoticum was used, to 56% in the case of P. chrysogenum and to 65% for C. fastidium, when grown at an external potential of − 10 MPa. Higher polyols were present in considerable quantity in both species but did not appear to be involved in osmotic adjustment. Potassium was the predominant cation in both species when grown on glucose, but chloride was insufficient to maintain electroneutrality. The potassium to sodium ratios were considerably higher in C. fastidium than P. chrysogenum, and inversely related to the external potential in the former species only. Glycerol and glucose were present in greater amounts at the margin than in older parts of large colonies of P. chrysogenum. High turgor potentials were apparently maintained throughout these large colonies which meant that the observed osmotic potential could not be accounted for by the solutes measured in older parts of the colony. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-128-11-2563