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Screening non-conventional yeasts for acid tolerance and engineering Pichia occidentalis for production of muconic acid.

ABSTRACT: Saccharomyces cerevisiae is a workhorse of industrial biotechnology owing to the organism's prominence in alcohol fermentation and the suite of sophisticated genetic tools available to manipulate its metabolism. However, S. cerevisiae is not suited to overproduce many bulk bioproducts, as toxicity constrains production at high titers. Here, we employ a high-throughput assay to screen 108 publicly accessible yeast strains for tolerance to 20 g L^-1 adipic acid (AA), a nylon precursor. We identify 15 tolerant yeasts and select Pichia occidentalis for production of cis,cis-muconic acid (CCM), the precursor to AA. By developing a genome editing toolkit for P. occidentalis, we demonstrate fed-batch production of CCM with a maximum titer (38.8 g L^-1), yield (0.134 g g^-1 glucose) and productivity (0.511 g L^-1 h^-1) that surpasses all metrics achieved using S. cerevisiae. This work brings us closer to the industrial bioproduction of AA and underscores the importance of host selection in bioprocessing.

SUBMITTER: Pyne ME

PROVIDER: S-EPMC10471774 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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Screening non-conventional yeasts for acid tolerance and engineering Pichia occidentalis for production of muconic acid.

Pyne Michael E ME Bagley James A JA Narcross Lauren L Kevvai Kaspar K Exley Kealan K Davies Meghan M Wang Qingzhao Q Whiteway Malcolm M Martin Vincent J J VJJ

Nature communications 20230831 1

Saccharomyces cerevisiae is a workhorse of industrial biotechnology owing to the organism's prominence in alcohol fermentation and the suite of sophisticated genetic tools available to manipulate its metabolism. However, S. cerevisiae is not suited to overproduce many bulk bioproducts, as toxicity constrains production at high titers. Here, we employ a high-throughput assay to screen 108 publicly accessible yeast strains for tolerance to 20 g L<sup>-1</sup> adipic acid (AA), a nylon precursor. W ...[more]

PMID: 37652930

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Dataset Information

Screening non-conventional yeasts for acid tolerance and engineering Pichia occidentalis for production of muconic acid.

Publications

Screening non-conventional yeasts for acid tolerance and engineering Pichia occidentalis for production of muconic acid.

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