The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis.
Trypanosoma brucei is a causative agent of the Human and Animal African Trypanosomiases. The mammalian stage parasites infect various tissues and organs including the bloodstream, central nervous system, skin, adipose tissue and lungs. They rely on ATP produced in glycolysis, consuming large amounts...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2024-02-01
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| Series: | PLoS Neglected Tropical Diseases |
| Online Access: | https://journals.plos.org/plosntds/article/file?id=10.1371/journal.pntd.0012007&type=printable |
| _version_ | 1797265464509857792 |
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| author | Julie Kovářová Martin Moos Michael P Barrett David Horn Alena Zíková |
| author_facet | Julie Kovářová Martin Moos Michael P Barrett David Horn Alena Zíková |
| author_sort | Julie Kovářová |
| collection | DOAJ |
| description | Trypanosoma brucei is a causative agent of the Human and Animal African Trypanosomiases. The mammalian stage parasites infect various tissues and organs including the bloodstream, central nervous system, skin, adipose tissue and lungs. They rely on ATP produced in glycolysis, consuming large amounts of glucose, which is readily available in the mammalian host. In addition to glucose, glycerol can also be used as a source of carbon and ATP and as a substrate for gluconeogenesis. However, the physiological relevance of glycerol-fed gluconeogenesis for the mammalian-infective life cycle forms remains elusive. To demonstrate its (in)dispensability, first we must identify the enzyme(s) of the pathway. Loss of the canonical gluconeogenic enzyme, fructose-1,6-bisphosphatase, does not abolish the process hence at least one other enzyme must participate in gluconeogenesis in trypanosomes. Using a combination of CRISPR/Cas9 gene editing and RNA interference, we generated mutants for four enzymes potentially capable of contributing to gluconeogenesis: fructose-1,6-bisphoshatase, sedoheptulose-1,7-bisphosphatase, phosphofructokinase and transaldolase, alone or in various combinations. Metabolomic analyses revealed that flux through gluconeogenesis was maintained irrespective of which of these genes were lost. Our data render unlikely a previously hypothesised role of a reverse phosphofructokinase reaction in gluconeogenesis and preclude the participation of a novel biochemical pathway involving transaldolase in the process. The sustained metabolic flux in gluconeogenesis in our mutants, including a triple-null strain, indicates the presence of a unique enzyme participating in gluconeogenesis. Additionally, the data provide new insights into gluconeogenesis and the pentose phosphate pathway, and improve the current understanding of carbon metabolism of the mammalian-infective stages of T. brucei. |
| first_indexed | 2024-04-25T00:45:13Z |
| format | Article |
| id | doaj.art-80c616d10ccd4ebb9a94e244ed85dd6a |
| institution | Directory Open Access Journal |
| issn | 1935-2727 1935-2735 |
| language | English |
| last_indexed | 2024-04-25T00:45:13Z |
| publishDate | 2024-02-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Neglected Tropical Diseases |
| spelling | doaj.art-80c616d10ccd4ebb9a94e244ed85dd6a2024-03-12T05:31:34ZengPublic Library of Science (PLoS)PLoS Neglected Tropical Diseases1935-27271935-27352024-02-01182e001200710.1371/journal.pntd.0012007The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis.Julie KovářováMartin MoosMichael P BarrettDavid HornAlena ZíkováTrypanosoma brucei is a causative agent of the Human and Animal African Trypanosomiases. The mammalian stage parasites infect various tissues and organs including the bloodstream, central nervous system, skin, adipose tissue and lungs. They rely on ATP produced in glycolysis, consuming large amounts of glucose, which is readily available in the mammalian host. In addition to glucose, glycerol can also be used as a source of carbon and ATP and as a substrate for gluconeogenesis. However, the physiological relevance of glycerol-fed gluconeogenesis for the mammalian-infective life cycle forms remains elusive. To demonstrate its (in)dispensability, first we must identify the enzyme(s) of the pathway. Loss of the canonical gluconeogenic enzyme, fructose-1,6-bisphosphatase, does not abolish the process hence at least one other enzyme must participate in gluconeogenesis in trypanosomes. Using a combination of CRISPR/Cas9 gene editing and RNA interference, we generated mutants for four enzymes potentially capable of contributing to gluconeogenesis: fructose-1,6-bisphoshatase, sedoheptulose-1,7-bisphosphatase, phosphofructokinase and transaldolase, alone or in various combinations. Metabolomic analyses revealed that flux through gluconeogenesis was maintained irrespective of which of these genes were lost. Our data render unlikely a previously hypothesised role of a reverse phosphofructokinase reaction in gluconeogenesis and preclude the participation of a novel biochemical pathway involving transaldolase in the process. The sustained metabolic flux in gluconeogenesis in our mutants, including a triple-null strain, indicates the presence of a unique enzyme participating in gluconeogenesis. Additionally, the data provide new insights into gluconeogenesis and the pentose phosphate pathway, and improve the current understanding of carbon metabolism of the mammalian-infective stages of T. brucei.https://journals.plos.org/plosntds/article/file?id=10.1371/journal.pntd.0012007&type=printable |
| spellingShingle | Julie Kovářová Martin Moos Michael P Barrett David Horn Alena Zíková The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis. PLoS Neglected Tropical Diseases |
| title | The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis. |
| title_full | The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis. |
| title_fullStr | The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis. |
| title_full_unstemmed | The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis. |
| title_short | The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis. |
| title_sort | bloodstream form of trypanosoma brucei displays non canonical gluconeogenesis |
| url | https://journals.plos.org/plosntds/article/file?id=10.1371/journal.pntd.0012007&type=printable |
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