Cargando…

Isocitrate Lyase and Succinate Semialdehyde Dehydrogenase Mediate the Synthesis of α-Ketoglutarate in Pseudomonas fluorescens

Glycerol is an important by-product of the biodiesel industry and its transformation into value-added products like keto acids is being actively pursued in order to improve the efficacy of this renewable energy sector. Here, we report that the enhanced production of α-ketoglutarate (KG) effected by...

Descripción completa

Detalles Bibliográficos
Autores principales: Alhasawi, Azhar A., Thomas, Sean C., Tharmalingam, Sujeethar, Legendre, Felix, Appanna, Vasu D.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6716453/
https://www.ncbi.nlm.nih.gov/pubmed/31507554
http://dx.doi.org/10.3389/fmicb.2019.01929
_version_ 1783447379868909568
author Alhasawi, Azhar A.
Thomas, Sean C.
Tharmalingam, Sujeethar
Legendre, Felix
Appanna, Vasu D.
author_facet Alhasawi, Azhar A.
Thomas, Sean C.
Tharmalingam, Sujeethar
Legendre, Felix
Appanna, Vasu D.
author_sort Alhasawi, Azhar A.
collection PubMed
description Glycerol is an important by-product of the biodiesel industry and its transformation into value-added products like keto acids is being actively pursued in order to improve the efficacy of this renewable energy sector. Here, we report that the enhanced production of α-ketoglutarate (KG) effected by Pseudomonas fluorescens in a mineral medium supplemented with manganese (Mn) is propelled by the increased activities of succinate semialdehyde dehydrogenase (SSADH), γ-aminobutyric acid aminotransaminase (GABAT), and isocitrate lyase (ICL). The latter generates glyoxylate and succinate two key metabolites involved in this process. Fumarate reductase (FRD) also aids in augmenting the pool of succinate, a precursor of succinate semialdehyde (SSA). The latter is then carboxylated to KG with the assistance of α-ketoglutarate decarboxylase (KDC). These enzymes work in tandem to ensure copious secretion of the keto acid. When incubated with glycerol in the presence of bicarbonate ([Formula: see text]), cell-free extracts readily produce KG with a metabolite fingerprint attributed to glutamate, γ-aminobutyric acid (GABA), succinate and succinate semialdehyde. Further targeted metabolomic and functional proteomic studies with high-performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR) and gel electrophoresis techniques provided molecular insights into this KG-generating machinery. Real-time quantitative polymerase chain reaction (RT-qPCR) analyses revealed the transcripts responsible for ICL and SSADH were elevated in the Mn-supplemented cultures. This hitherto unreported metabolic network where ICL and SSADH orchestrate the enhanced production of KG from glycerol, provides an elegant means of converting an industrial waste into a keto acid with wide-ranging application in the medical, cosmetic, and chemical sectors.
format Online
Article
Text
id pubmed-6716453
institution National Center for Biotechnology Information
language English
publishDate 2019
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-67164532019-09-10 Isocitrate Lyase and Succinate Semialdehyde Dehydrogenase Mediate the Synthesis of α-Ketoglutarate in Pseudomonas fluorescens Alhasawi, Azhar A. Thomas, Sean C. Tharmalingam, Sujeethar Legendre, Felix Appanna, Vasu D. Front Microbiol Microbiology Glycerol is an important by-product of the biodiesel industry and its transformation into value-added products like keto acids is being actively pursued in order to improve the efficacy of this renewable energy sector. Here, we report that the enhanced production of α-ketoglutarate (KG) effected by Pseudomonas fluorescens in a mineral medium supplemented with manganese (Mn) is propelled by the increased activities of succinate semialdehyde dehydrogenase (SSADH), γ-aminobutyric acid aminotransaminase (GABAT), and isocitrate lyase (ICL). The latter generates glyoxylate and succinate two key metabolites involved in this process. Fumarate reductase (FRD) also aids in augmenting the pool of succinate, a precursor of succinate semialdehyde (SSA). The latter is then carboxylated to KG with the assistance of α-ketoglutarate decarboxylase (KDC). These enzymes work in tandem to ensure copious secretion of the keto acid. When incubated with glycerol in the presence of bicarbonate ([Formula: see text]), cell-free extracts readily produce KG with a metabolite fingerprint attributed to glutamate, γ-aminobutyric acid (GABA), succinate and succinate semialdehyde. Further targeted metabolomic and functional proteomic studies with high-performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR) and gel electrophoresis techniques provided molecular insights into this KG-generating machinery. Real-time quantitative polymerase chain reaction (RT-qPCR) analyses revealed the transcripts responsible for ICL and SSADH were elevated in the Mn-supplemented cultures. This hitherto unreported metabolic network where ICL and SSADH orchestrate the enhanced production of KG from glycerol, provides an elegant means of converting an industrial waste into a keto acid with wide-ranging application in the medical, cosmetic, and chemical sectors. Frontiers Media S.A. 2019-08-23 /pmc/articles/PMC6716453/ /pubmed/31507554 http://dx.doi.org/10.3389/fmicb.2019.01929 Text en Copyright © 2019 Alhasawi, Thomas, Tharmalingam, Legendre and Appanna. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Microbiology
Alhasawi, Azhar A.
Thomas, Sean C.
Tharmalingam, Sujeethar
Legendre, Felix
Appanna, Vasu D.
Isocitrate Lyase and Succinate Semialdehyde Dehydrogenase Mediate the Synthesis of α-Ketoglutarate in Pseudomonas fluorescens
title Isocitrate Lyase and Succinate Semialdehyde Dehydrogenase Mediate the Synthesis of α-Ketoglutarate in Pseudomonas fluorescens
title_full Isocitrate Lyase and Succinate Semialdehyde Dehydrogenase Mediate the Synthesis of α-Ketoglutarate in Pseudomonas fluorescens
title_fullStr Isocitrate Lyase and Succinate Semialdehyde Dehydrogenase Mediate the Synthesis of α-Ketoglutarate in Pseudomonas fluorescens
title_full_unstemmed Isocitrate Lyase and Succinate Semialdehyde Dehydrogenase Mediate the Synthesis of α-Ketoglutarate in Pseudomonas fluorescens
title_short Isocitrate Lyase and Succinate Semialdehyde Dehydrogenase Mediate the Synthesis of α-Ketoglutarate in Pseudomonas fluorescens
title_sort isocitrate lyase and succinate semialdehyde dehydrogenase mediate the synthesis of α-ketoglutarate in pseudomonas fluorescens
topic Microbiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6716453/
https://www.ncbi.nlm.nih.gov/pubmed/31507554
http://dx.doi.org/10.3389/fmicb.2019.01929
work_keys_str_mv AT alhasawiazhara isocitratelyaseandsuccinatesemialdehydedehydrogenasemediatethesynthesisofaketoglutarateinpseudomonasfluorescens
AT thomasseanc isocitratelyaseandsuccinatesemialdehydedehydrogenasemediatethesynthesisofaketoglutarateinpseudomonasfluorescens
AT tharmalingamsujeethar isocitratelyaseandsuccinatesemialdehydedehydrogenasemediatethesynthesisofaketoglutarateinpseudomonasfluorescens
AT legendrefelix isocitratelyaseandsuccinatesemialdehydedehydrogenasemediatethesynthesisofaketoglutarateinpseudomonasfluorescens
AT appannavasud isocitratelyaseandsuccinatesemialdehydedehydrogenasemediatethesynthesisofaketoglutarateinpseudomonasfluorescens