Comparison of three expression systems for heterologous xylanase production by S. cerevisiae in defined medium

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dc.contributor.authorGorgens J.F.
dc.contributor.authorPlanas J.
dc.contributor.authorvan Zyl W.H.
dc.contributor.authorKnoetze J.H.
dc.contributor.authorHahn-Hagerdal B.
dc.date.accessioned2011-05-15T16:05:34Z
dc.date.available2011-05-15T16:05:34Z
dc.date.issued2004
dc.description.abstractThe influence of the auxotrophic deficiencies of the host strain and expression vector selection on the production of a heterologous protein was investigated. Heterologous xylanase production by two prototrophic S. cerevisiae transformants, containing either a plasmid-based, YEp-type expression system or an integrative, YIp-type expression system, were compared with production by an auxotrophic transformant, containing an identical YEp-type expression system, in batch and continuous cultivation, using a chemically defined medium. Heterologous xylanase production by the auxotrophic strains in defined medium was critically dependent on the availability of amino acids, as extracellular xylanase production increased dramatically when amino acids were over-consumed from the medium to the point of saturating the cell. Saturation with amino acids, indicated by an increased leakage of amino acids from the cell, was thus a prerequisite for high level of heterologous; protein production by the auxotrophic strain. Maximal xylanase production levels by the auxotrophic strain corresponded to the levels obtained with a similar prototrophic strain during cultivation in defined medium without amino acids. Superfluous auxotrophic markers thus had a strong deleterious effect on heterologous protein production by recombinant yeasts, and the use of such strains should be limited to initial exploratory investigations. The increased copy number and foreign gene dosage of the YEp-based expression vector, stabilized by the ura3 fur1 autoselection system, significantly improved production levels of heterologous xylanase, compared to the YIp system, which is based on a single integration into the yeast genome. No evidence was found of the possible saturation of the host secretory capacity by multicopy overexpression. Stable production of heterologous xylanase at high levels by the prototrophic YEp-based recombinant strain, compared to the YIp system, was demonstrated. Copyright © 2004 John Wiley & Sons, Ltd.
dc.description.versionArticle
dc.identifier.citationYeast
dc.identifier.citation21
dc.identifier.citation14
dc.identifier.issn0749503X
dc.identifier.other10.1002/yea.1175
dc.identifier.urihttp://hdl.handle.net/10019.1/13189
dc.subjectamino acid
dc.subjectxylan endo 1,3 beta xylosidase
dc.subjectarticle
dc.subjectauxotrophy
dc.subjectcontinuous culture
dc.subjectcontrolled study
dc.subjectculture medium
dc.subjectenzyme synthesis
dc.subjectexpression vector
dc.subjectfungal strain
dc.subjectgene dosage
dc.subjectgenetic transformation
dc.subjectgenome
dc.subjecthost
dc.subjectnonhuman
dc.subjectplasmid
dc.subjectpriority journal
dc.subjectprotein expression
dc.subjectSaccharomyces cerevisiae
dc.subjectyeast cell
dc.subjectAmino Acids
dc.subjectBiomass
dc.subjectBioreactors
dc.subjectEndo-1,4-beta Xylanases
dc.subjectFermentation
dc.subjectGenetic Vectors
dc.subjectPlasmids
dc.subjectSaccharomyces cerevisiae
dc.subjectTransformation, Genetic
dc.titleComparison of three expression systems for heterologous xylanase production by S. cerevisiae in defined medium
dc.typeArticle
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