Impact of Classical Strain Improvement of Penicillium rubens on Amino Acid Metabolism during β-Lactam Production.

ABSTRACT: To produce high levels of β-lactams, the filamentous fungus Penicillium rubens (previously named Penicillium chrysogenum) has been subjected to an extensive classical strain improvement (CSI) program during the last few decades. This has led to the accumulation of many mutations that were spread over the genome. Detailed analysis reveals that several mutations targeted genes that encode enzymes involved in amino acid metabolism, in particular biosynthesis of l-cysteine, one of the amino acids used for β-lactam production. To examine the impact of the mutations on enzyme function, the respective genes with and without the mutations were cloned and expressed in Escherichia coli, purified, and enzymatically analyzed. Mutations severely impaired the activities of a threonine and serine deamina

SUBMITTER: Wu M 

PROVIDER: S-EPMC6974646 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature