Influence of oxygen starvation on the respiratory capacity of Penicillium chrysogenum

SummaryThe sensitivity of Penicillium chrysogenum to oxygen starvation and to azide was investigated on cells taken from different phases of a penicillin process. These treatments caused irreversible inhibition of the oxygen uptake rate during the tropophase while the idiophase cells were resistant to either treatment. The azide resistance is supposed to depend only on the dissociation of the hydrazoic acid when the process pH increases, but the shift from sensitive to resistant cells with respect to oxygen starvation was neither caused by the pH-change nor by the glucose limitation. Inactivation (IOUR, percentage) of tropophase cells followed 1st order kinetics according to ln (1-IOUR/100)-1=0.048·t, where t is given in minutes. This means that the 1st minute of oxygen starvation may reduce the metabolic capacity by 4.7%.