Optimization of Candida tropicalis cytochrome P450alk gene expression in Saccharomyces cerevisiae with continuous cultures
Details
Serval ID
serval:BIB_06B429E3537B
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Optimization of Candida tropicalis cytochrome P450alk gene expression in Saccharomyces cerevisiae with continuous cultures
Journal
Applied Microbiology and Biotechnology
ISSN
0175-7598 (Print)
Publication state
Published
Issued date
10/1991
Volume
36
Number
1
Pages
48-60
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Oct
Research Support, Non-U.S. Gov't --- Old month value: Oct
Abstract
The cytochrome P450alk gene (P45alk) from Candida tropicalis ATCC 750 was expressed in Saccharomyces cerevisiae GRF18 under control of the alcohol dehydrogenase I (ADHI) promoter. To achieve stable expression over long time periods, a 2-microns derived replicative and an integrative expression system were tested in continuous culture. The 2-microns derived replicative system could not be maintained in cells over high generation numbers. In continuous culture, the instability was more pronounced at high dilution rates (D) and high histidine concentration, for which the yeast is auxotrophic. The nature of the instability was probably due to a gene conversion event between the plasmid and the yeast chromosome. In contrast, the integrative expression system was stably maintained in cells over prolonged cultivation times. Since this work focused on the production of large quantities of P450 by heterologous expression in yeast over prolonged time periods, the integrant was used to optimize P450alk expression by varying continuous culture parameters. The P450alk expression was shown to be dependent on the D applied to the culture. The highest P450alk expression levels were obtained at high D, when cell metabolism was shifted to partial glucose oxidation, yielding ethanol as a major metabolite in the culture supernatant. In contrast, when glucose was completely oxidized at low D, the ADHI-dependent P450alk expression was reduced and followed by a corresponding decrease in heterologous protein.
Keywords
Alcohol Dehydrogenase/genetics
Alkane 1-Monooxygenase
Candida/*genetics
Chromosomes, Fungal/metabolism
Cytochrome P-450 Enzyme System/*biosynthesis/genetics
Fungal Proteins/*biosynthesis/genetics
Gene Conversion
*Gene Expression Regulation, Fungal
Genes, Fungal
Genetic Vectors
Mixed Function Oxygenases/*biosynthesis/genetics
Plasmids
Promoter Regions (Genetics)
Recombinant Fusion Proteins/*biosynthesis/genetics
Recombination, Genetic
Saccharomyces cerevisiae/genetics/growth & development/*metabolism
Pubmed
Web of science
Create date
25/01/2008 15:40
Last modification date
20/08/2019 13:28