Enhancement of protein secretion in Saccharomyces cerevisiae by overproduction of Sso protein, a late-acting component of the secretory machinery

Laura Ruohonen, Jaana Toikkanen, Ville Tieaho, Mika Outola, Hans Söderlund, Sirkka Keränen*

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

71 Citations (Scopus)

Abstract

Increased production of secreted proteins in Saccharomyces cerevisiae was achieved by overexpressing the yeast syntaxins, Sso1 or Sso2 protein, the t-SNAREs functioning at the targeting/fusion of the Golgi-derived secretory vesicles to the plasma membrane. Up to four- or six-fold yields of a heterologous secreted protein, Bacillus α-amylase, or an endogenous secreted protein, invertase, were obtained respectively when expressing either one of the SSO genes, SSO1 or SSO2, from the ADH1 promoter on a multicopy plasmid. Direct correlation between the Sso protein level and the amount of secreted α-amylase was demonstrated by modulating the expression level of the SSO2 gene. Quantitation of the α-amylase activity in the culture medium, periplasmic space and cytoplasm suggests that secretion into the periplasmic space is the primary stage at which the SSO genes exert the secretion-enhancing function. Pulse-chase data also support enhanced secretion efficiency obtained by SSO overexpression. Our data suggest that the Sso proteins may be rate-limiting components of the protein secretion machinery at the exocytosis step in yeast.

Original languageEnglish
Pages (from-to)337-351
JournalYeast
Volume13
Issue number4
DOIs
Publication statusPublished - 1997
MoE publication typeA1 Journal article-refereed

Fingerprint

Dive into the research topics of 'Enhancement of protein secretion in Saccharomyces cerevisiae by overproduction of Sso protein, a late-acting component of the secretory machinery'. Together they form a unique fingerprint.

Cite this