ACCUMULATION OF INTRACELLULAR INORGANIC SULFATE BY PENICILLIUM CHRYSOGENUM

Abstract

The intracellular distribution and concentration of sulfur-35 was investigated in the mycelium of several related strains of P. chrysogenum grown on Na2S35O4 as the sole S source. It was found that a high 24 as the sole S source. It was found that a high penicillin-producing strain (51-20F3) could concentrate inorganic sulfate within its mycelium to a level of 25 to 35 m[image] (5-6 times that in the extracellular medium). Other high and low penicillin-producing strains could concentrate inorganic sulfate only to a level of about 5 m[image]. The enhanced ability of strain 51-20F3 to accumulate inorganic sulfate may be a reflection of the same mutation that resulted in the ability of this strain to produce increased yields of penicillin on media containing penicillin R-group precursor. The mutation probably resulted in the loss of a specific control mechanism that limits the operation of the sulfate-transfer mechanism. The accumulated sulfate appears to be free ionic sulfate. It was observed that cysteine or methionine, when present in the medium in equimolar amounts (6.9 mM) with inorganic sulfate, apparently suppressed the intracellular sulfate accumulation by 65-80%.