Substrate cycles in <it>Penicillium chrysogenum</it> quantified by isotopic non-stationary flux analysis
<p>Abstract</p> <p>Background</p> <p><it>Penicillium chrysogenum</it>, the main production strain for penicillin-G, has a high content of intracellular carbohydrates, especially reduced sugars such as mannitol, arabitol, erythritol, as well as trehalose and...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2012-10-01
|
| Series: | Microbial Cell Factories |
| Online Access: | http://www.microbialcellfactories.com/content/11/1/140 |
| _version_ | 1818934608423550976 |
|---|---|
| author | Zhao Zheng ten Pierick Angela de Jonge Lodewijk Heijnen Joseph J Wahl S Aljoscha |
| author_facet | Zhao Zheng ten Pierick Angela de Jonge Lodewijk Heijnen Joseph J Wahl S Aljoscha |
| author_sort | Zhao Zheng |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p><it>Penicillium chrysogenum</it>, the main production strain for penicillin-G, has a high content of intracellular carbohydrates, especially reduced sugars such as mannitol, arabitol, erythritol, as well as trehalose and glycogen. In previous steady state <sup>13</sup>C wash-in experiments a delay of labeling enrichments in glycolytic intermediates was observed, which suggests turnover of storage carbohydrates. The turnover of storage pools consumes ATP which is expected to reduce the product yield for energy demanding production pathways like penicillin-G.</p> <p>Results</p> <p>In this study, a <sup>13</sup>C labeling wash-in experiment of 1 hour was performed to systematically quantify the intracellular flux distribution including eight substrate cycles. The experiments were performed using a mixed carbon source of 85% Cmol<sub>Glc</sub>/Cmol<sub>Glc+EtOH</sub> labeled glucose (mixture of 90% [1-<sup>13</sup>C<sub>1</sub>] and 10% [U-<sup>13</sup>C<sub>6</sub>]) and 15% ethanol [U-<sup>13</sup>C<sub>2</sub>]. It was found, that (1) also several extracellular pools are enriched with <sup>13</sup>C labeling rapidly (trehalose, mannitol, and others), (2) the intra- to extracellular metabolite concentration ratios were comparable for a large set of metabolites while for some carbohydrates (mannitol, trehalose, and glucose) the measured ratios were much higher.</p> <p>Conclusions</p> <p>The fast enrichment of several extracellular carbohydrates and a concentration ratio higher than the ratio expected from cell lysis (2%) indicate active (e.g. ATP consuming) transport cycles over the cellular membrane. The flux estimation indicates, that substrate cycles account for about 52% of the gap in the ATP balance based on metabolic flux analysis.</p> |
| first_indexed | 2024-12-20T05:06:59Z |
| format | Article |
| id | doaj.art-8440abeef41f4b149d025291f5e5678a |
| institution | Directory Open Access Journal |
| issn | 1475-2859 |
| language | English |
| last_indexed | 2024-12-20T05:06:59Z |
| publishDate | 2012-10-01 |
| publisher | BMC |
| record_format | Article |
| series | Microbial Cell Factories |
| spelling | doaj.art-8440abeef41f4b149d025291f5e5678a2022-12-21T19:52:22ZengBMCMicrobial Cell Factories1475-28592012-10-0111114010.1186/1475-2859-11-140Substrate cycles in <it>Penicillium chrysogenum</it> quantified by isotopic non-stationary flux analysisZhao Zhengten Pierick Angelade Jonge LodewijkHeijnen Joseph JWahl S Aljoscha<p>Abstract</p> <p>Background</p> <p><it>Penicillium chrysogenum</it>, the main production strain for penicillin-G, has a high content of intracellular carbohydrates, especially reduced sugars such as mannitol, arabitol, erythritol, as well as trehalose and glycogen. In previous steady state <sup>13</sup>C wash-in experiments a delay of labeling enrichments in glycolytic intermediates was observed, which suggests turnover of storage carbohydrates. The turnover of storage pools consumes ATP which is expected to reduce the product yield for energy demanding production pathways like penicillin-G.</p> <p>Results</p> <p>In this study, a <sup>13</sup>C labeling wash-in experiment of 1 hour was performed to systematically quantify the intracellular flux distribution including eight substrate cycles. The experiments were performed using a mixed carbon source of 85% Cmol<sub>Glc</sub>/Cmol<sub>Glc+EtOH</sub> labeled glucose (mixture of 90% [1-<sup>13</sup>C<sub>1</sub>] and 10% [U-<sup>13</sup>C<sub>6</sub>]) and 15% ethanol [U-<sup>13</sup>C<sub>2</sub>]. It was found, that (1) also several extracellular pools are enriched with <sup>13</sup>C labeling rapidly (trehalose, mannitol, and others), (2) the intra- to extracellular metabolite concentration ratios were comparable for a large set of metabolites while for some carbohydrates (mannitol, trehalose, and glucose) the measured ratios were much higher.</p> <p>Conclusions</p> <p>The fast enrichment of several extracellular carbohydrates and a concentration ratio higher than the ratio expected from cell lysis (2%) indicate active (e.g. ATP consuming) transport cycles over the cellular membrane. The flux estimation indicates, that substrate cycles account for about 52% of the gap in the ATP balance based on metabolic flux analysis.</p>http://www.microbialcellfactories.com/content/11/1/140 |
| spellingShingle | Zhao Zheng ten Pierick Angela de Jonge Lodewijk Heijnen Joseph J Wahl S Aljoscha Substrate cycles in <it>Penicillium chrysogenum</it> quantified by isotopic non-stationary flux analysis Microbial Cell Factories |
| title | Substrate cycles in <it>Penicillium chrysogenum</it> quantified by isotopic non-stationary flux analysis |
| title_full | Substrate cycles in <it>Penicillium chrysogenum</it> quantified by isotopic non-stationary flux analysis |
| title_fullStr | Substrate cycles in <it>Penicillium chrysogenum</it> quantified by isotopic non-stationary flux analysis |
| title_full_unstemmed | Substrate cycles in <it>Penicillium chrysogenum</it> quantified by isotopic non-stationary flux analysis |
| title_short | Substrate cycles in <it>Penicillium chrysogenum</it> quantified by isotopic non-stationary flux analysis |
| title_sort | substrate cycles in it penicillium chrysogenum it quantified by isotopic non stationary flux analysis |
| url | http://www.microbialcellfactories.com/content/11/1/140 |
| work_keys_str_mv | AT zhaozheng substratecyclesinitpenicilliumchrysogenumitquantifiedbyisotopicnonstationaryfluxanalysis AT tenpierickangela substratecyclesinitpenicilliumchrysogenumitquantifiedbyisotopicnonstationaryfluxanalysis AT dejongelodewijk substratecyclesinitpenicilliumchrysogenumitquantifiedbyisotopicnonstationaryfluxanalysis AT heijnenjosephj substratecyclesinitpenicilliumchrysogenumitquantifiedbyisotopicnonstationaryfluxanalysis AT wahlsaljoscha substratecyclesinitpenicilliumchrysogenumitquantifiedbyisotopicnonstationaryfluxanalysis |