Effect of ammonium as nitrogen source on production of .DELTA.-(L-.ALPHA.-aminoadiply)-L-cysteinyl-D-valine synthetase by Cephalosporium acremonium C-10.

Publisher Website
Google Scholar
Abstract
Cephalosporin production by Cephalosporium acremonium strain C-10 was suppressed when the organic nitrogen source (1.2% L-asparagine) was replaced by 1.2% (NH4)2SO4. A higher level of (NH4)2SO4 (3.5%) led to even greater suppression. Ammonium repression was exerted on formation of .delta.-(L-.alpha.-aminoadipyl)-L-cysteinyl-D-valine (ACV) synthetase, together with that of expandase; a lesser effect by ammonium was observed on cyclase production. Inhibition of ACV synthetase activity by ammonium was also observed (ca. 50% inhibition at 250 mM HN4+).