RT Journal Article SR Electronic(1) A1 Gadd, G. M. A1 Chudek, J. A. A1 Foster, R. A1 Reed, R. H.YR 1984 T1 The Osmotic Responses of Penicillium ochro-chloron: Changes in Internal Solute Levels in Response to Copper and Salt Stress JF Microbiology, VO 130 IS 8 SP 1969 OP 1975 DO https://doi.org/10.1099/00221287-130-8-1969 PB Microbiology Society, SN 1465-2080, AB The marked copper tolerance of Penicillium ochro-chloron has been confirmed as has its ability to grow in solutions of high salinity. The major low molecular weight organic solutes present in P. ochro-chloron were glycerol, erythritol, arabitol, mannitol, sorbitol and trehalose. Of these, glycerol increased significantly during growth in high concentrations of Na+ or Cu2+, a 15-fold increase, relative to the control, occurring in concentrations of 0.5 M. Cell K+ increased with elevated external Na+ but decreased slightly with elevated external Cu2+. With high external Cu2+ mycelium maintained a constant level of Cu2+, with low levels of Na+ in all treatments. It is concluded that the high concentrations of glycerol induced by high external Na+ or Cu2+ had a significant osmotic effect, allowing growth in media of high osmolality. The exclusion of ions may have a gratuitous role in the copper tolerance of P. ochro-chloron., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-130-8-1969