Effects of replacement of promoters and modification of the leader peptide region of the amy gene of Streptomyces griseus on synthesis and secretion of α-amylase by Streptomyces lividans
✍ Scribed by Vigal, Tomás ;Gil, José A. ;Daza, Antonio ;García-González, M. Dolores ;Villadas, Pablo ;Martín, Juan F.
- Book ID
- 104708736
- Publisher
- Springer
- Year
- 1991
- Tongue
- English
- Weight
- 872 KB
- Volume
- 231
- Category
- Article
- ISSN
- 0026-8925
No coin nor oath required. For personal study only.
✦ Synopsis
Five different mutations were introduced into the leader peptide region of the alpha-amylase gene of Streptomyces griseus IMRU 3570. A mutation which increased the positive charge of the N-terminal region of the leader peptide enhanced the secretion of alpha-amylase by two- to threefold. Replacement of the native promoter of the amylase gene by the promoter of the Tn5 neo gene or by the promoter of the saf gene resulted in a 16-fold increase in alpha-amylase secretion. The enhanced secretion of alpha-amylase obtained by using the most efficient promoters was due to a correlated increase in the amount of transcript formed. The translation and secretion processes in S. lividans are not a bottleneck for enzyme secretion even at very high transcription rates, since stimulation of transcription of the alpha-amylase gene results in a proportionate increase in secretion of the enzyme.