Comparative Proteomics Analysis of Engineered Saccharomyces cerevisiae with Enhanced Biofuel Precursor Production

Abstract

The yeast Saccharomyces cerevisiae was metabolically modified for enhanced biofuel precursor production by knocking out genes encoding mitochondrial isocitrate dehydrogenase and over-expression of a heterologous ATP-citrate lyase. A comparative iTRAQ-coupled 2D LC-MS/MS analysis was performed to obtain a global overview of ubiquitous protein expression changes in S. cerevisiae engineered strains. More than 300 proteins were identified. Among these proteins, 37 were found differentially expressed in engineered strains and they were classified into specific categories based on their enzyme functions. Most of the proteins involved in glycolytic and pyruvate branch-point pathways were found to be up-regulated and the proteins involved in respiration and glyoxylate pathway were however found to be down-regulated in engineered strains. Moreover, the metabolic modification of S. cerevisiae cells resulted in a number of up-regulated proteins involved in stress response and differentially expressed proteins involved in amino acid metabolism and protein biosynthesis pathways. These LC-MS/MS based proteomics analysis results not only offered extensive information in identifying potential protein-protein interactions, signal pathways and ubiquitous cellular changes elicited by the engineered pathways, but also provided a meaningful biological information platform serving further modification of yeast cells for enhanced biofuel production.

Quantitative mass spectrometry-based multiplexing compares the abundance of 5000 S. cerevisiae proteins across 10 carbon sources

“…In industrial applications, S. cerevisiae has been used traditionally for brewing and baking, and more recently for the development of biofuels [2, 3]. A common mechanism of manipulating the metabolic processes governing S. cerevisiae is shifting carbon sources [4].…”

Proteome-wide quantitative multiplexed profiling of protein expression: carbon-source dependency inSaccharomyces cerevisiae

“…In industrial applications, S. cerevisiae has been used traditionally for brewing and baking, and more recently for biofuels ( Raghavulu et al. , 2011 ; Tang et al. , 2013b ).…”

The significance of proline and glutamate on butanol chaotropic stress in Bacillus subtilis 168

“…Nevertheless, it is worthwhile to note some differences. While a native butanol-producing strain, Clostridium acetobutylicum , responded to butanol-challenged conditions with 102 responsive proteins that are mainly involved in amino acid metabolism and protein synthesis in addition to solvent formation-related proteins [ 43 ], other potential heterologous hosts for butanol production exhibited various numbers of differentially expressed proteins (generally at 1.5- to 2-fold changes) when subjected to butanol stress, the majority of which are transporters, oxidative stress response proteins, and proteins related to energy metabolism [ 41 – 46 ]; these include (in brackets, the numbers of butanol-responsive proteins assessed by proteomic analysis of each organism) E. coli [997] [ 44 ], P. putida [138] [ 41 ], Staphylococcus warneri SG1 [108] [ 42 ], Saccharomyces cerevisiae [>300] [ 47 ], and Synechocystis sp. PCC 6803 [177] [ 45 ].…”