Transcriptional monitoring of steady state and effects of anaerobic phases in chemostat cultures of the filamentous fungus Trichoderma reesei

Abstract

Background: Chemostat cultures are commonly used in production of cellular material for systems-wide biological studies. We have used the novel TRAC (transcript analysis with aid of affinity capture) method to study expression stability of approximately 30 process relevant marker genes in chemostat cultures of the filamentous fungus Trichoderma reesei and its transformant expressing laccase from Melanocarpus albomyces. Transcriptional responses caused by transient oxygen deprivations and production of foreign protein were also studied in T. reesei by TRAC.

Systems biological approaches towards understanding cellulase production by Trichoderma reesei

“…Rautio et al (2006) also found that the respiratory pathway in T. reesei is not regulated by the carbon catabolite repressor CRE1, and only minor differences were observed in the ratio of the relative anaplerotic flux to the respirative pathway flux of the wild type and the Δ cre1 T. reesei strains. This indicates that CRE1 does not mediate carbon source dependent metabolic state alterations in the central carbon metabolism of T. reesei , what is consistent with the transcriptomic data by Portnoy et al (2011; vide supra ).…”

“…Towards a quantitative description of metabolic fluxes during cellulase formation, Rautio et al (2006) used a metabolomic C13 partitioning analysis for quantifying fluxes through the carbon catabolic and anabolic pathways. They found that the induction of cellulase gene expression with sophorose did not result in significant changes in the ratio of anabolic and oxidative activities of the TCA cycle.…”

Central carbon metabolism ofSaccharomyces cerevisiaein anaerobic, oxygen-limited and fully aerobic steady-state conditions and following a shift to anaerobic conditions

“…in aerobic and anaerobic conditions), but rather provides an indication of the ongoing cellular response to the shift, relative to the stable condition prior to it. It is also worth noting that S. cerevisiae appears to require more time to adjust to a change in conditions than does the filamentous fungus Trichoderma reesei, which is able to attain transcriptional steady state within less than one generation (Rautio et al, 2006b). The adaptation to anaerobic conditions (four to five generations) was, however, more rapid than the time needed for S. cerevisiae to achieve transcriptional steady state following a shift from growth on galactose to growth on glucose (4 10 generations; 4 43 h at D = 0.16 h À1 ; Braun & Brenner, 2004).…”

The Genomes of Three Uneven Siblings: Footprints of the Lifestyles of Three Trichoderma Species

“…Members of this family were also shown to be induced during developmental changes (910). In T. reesei the transcription of HSP70 was strongly induced under anaerobic conditions (911). The overexpression of the HSP70 gene of T. harzianum resulted in a higher tolerance to oxidative, osmotic, and salt stress factors after heat pretreatment of the conidia (912).…”