Comparative proteomics investigation of central carbon metabolism in Euglena gracilis grown under predominantly phototrophic, mixotrophic and heterotrophic cultivations

Mafruha T. Hasan, Angela Sun, Bishal Khatiwada, Leon McQuade, Mehdi Mirzaei, Junior Te'o, Graham Hobba, Anwar Sunna, Helena Nevalainen

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Euglena gracilis can use a wide range of organic carbon sources, as well as CO2 from the atmosphere. This metabolic versatility is owed to the genome of E. gracilis that can encode a wide range of enzymes. Many of these enzymes are regulated post-transcriptionally, allowing the cells to adapt quickly to changes in their surroundings. Here we investigated the effect of predominantly phototrophic (PT), mixotrophic (MT) and heterotrophic (HT) cultivation on central carbon metabolism in E. gracilis Z using label-free shotgun proteomics. Differential expression between isozymes was observed based on the cultivation condition. A hexokinase enzyme identified in the published transcriptome was not detected in the proteome. Instead, a high-specificity glucokinase appeared to conduct the first step of glycolysis. Two candidates for paramylon synthase were identified (EgGSL1 and EgGSL2), of which the predominant EgGSL2 protein was detected across all growth conditions, while EgGSL1 was only detected in the presence of light (PT and MT cultivations). Proteomic analysis revealed that the oxidative pentose phosphate pathway also plays a key role in glucose metabolism under MT and HT cultivation. Some chloroplast-encoded proteins and enzymes of the Calvin pathway were detected under HT cultivation indicating regulation at the post-translational level. The carbon metabolic pathways investigated here in terms of proteomic changes provide new information, as well as validate data presented elsewhere with quantitative proteomics, adding to the existing knowledge of metabolism in E. gracilis. Putative functional annotations of several proteins that were previously unidentified are also provided.

LanguageEnglish
Article number101638
Number of pages11
JournalAlgal Research
Volume43
DOIs
Publication statusPublished - Nov 2019

Fingerprint

Euglena gracilis
proteomics
metabolism
carbon
enzymes
glucokinase
hexokinase
proteins
pentoses
glycolysis
proteome
transcriptome
biochemical pathways
isozymes
chloroplasts
phosphates
glucose
genome
cells

Keywords

  • Carbon metabolism
  • Glucokinase
  • Paramylon synthesis
  • Post-transcriptional regulation
  • Euglena gracilis proteomics

Cite this

@article{cc2905f504e54018bf31528092e7e13d,
title = "Comparative proteomics investigation of central carbon metabolism in Euglena gracilis grown under predominantly phototrophic, mixotrophic and heterotrophic cultivations",
abstract = "Euglena gracilis can use a wide range of organic carbon sources, as well as CO2 from the atmosphere. This metabolic versatility is owed to the genome of E. gracilis that can encode a wide range of enzymes. Many of these enzymes are regulated post-transcriptionally, allowing the cells to adapt quickly to changes in their surroundings. Here we investigated the effect of predominantly phototrophic (PT), mixotrophic (MT) and heterotrophic (HT) cultivation on central carbon metabolism in E. gracilis Z using label-free shotgun proteomics. Differential expression between isozymes was observed based on the cultivation condition. A hexokinase enzyme identified in the published transcriptome was not detected in the proteome. Instead, a high-specificity glucokinase appeared to conduct the first step of glycolysis. Two candidates for paramylon synthase were identified (EgGSL1 and EgGSL2), of which the predominant EgGSL2 protein was detected across all growth conditions, while EgGSL1 was only detected in the presence of light (PT and MT cultivations). Proteomic analysis revealed that the oxidative pentose phosphate pathway also plays a key role in glucose metabolism under MT and HT cultivation. Some chloroplast-encoded proteins and enzymes of the Calvin pathway were detected under HT cultivation indicating regulation at the post-translational level. The carbon metabolic pathways investigated here in terms of proteomic changes provide new information, as well as validate data presented elsewhere with quantitative proteomics, adding to the existing knowledge of metabolism in E. gracilis. Putative functional annotations of several proteins that were previously unidentified are also provided.",
keywords = "Carbon metabolism, Glucokinase, Paramylon synthesis, Post-transcriptional regulation, Euglena gracilis proteomics",
author = "Hasan, {Mafruha T.} and Angela Sun and Bishal Khatiwada and Leon McQuade and Mehdi Mirzaei and Junior Te'o and Graham Hobba and Anwar Sunna and Helena Nevalainen",
year = "2019",
month = "11",
doi = "10.1016/j.algal.2019.101638",
language = "English",
volume = "43",
journal = "Algal Research",
issn = "2211-9264",
publisher = "Elsevier",

}

TY - JOUR

T1 - Comparative proteomics investigation of central carbon metabolism in Euglena gracilis grown under predominantly phototrophic, mixotrophic and heterotrophic cultivations

AU - Hasan, Mafruha T.

AU - Sun, Angela

AU - Khatiwada, Bishal

AU - McQuade, Leon

AU - Mirzaei, Mehdi

AU - Te'o, Junior

AU - Hobba, Graham

AU - Sunna, Anwar

AU - Nevalainen, Helena

PY - 2019/11

Y1 - 2019/11

N2 - Euglena gracilis can use a wide range of organic carbon sources, as well as CO2 from the atmosphere. This metabolic versatility is owed to the genome of E. gracilis that can encode a wide range of enzymes. Many of these enzymes are regulated post-transcriptionally, allowing the cells to adapt quickly to changes in their surroundings. Here we investigated the effect of predominantly phototrophic (PT), mixotrophic (MT) and heterotrophic (HT) cultivation on central carbon metabolism in E. gracilis Z using label-free shotgun proteomics. Differential expression between isozymes was observed based on the cultivation condition. A hexokinase enzyme identified in the published transcriptome was not detected in the proteome. Instead, a high-specificity glucokinase appeared to conduct the first step of glycolysis. Two candidates for paramylon synthase were identified (EgGSL1 and EgGSL2), of which the predominant EgGSL2 protein was detected across all growth conditions, while EgGSL1 was only detected in the presence of light (PT and MT cultivations). Proteomic analysis revealed that the oxidative pentose phosphate pathway also plays a key role in glucose metabolism under MT and HT cultivation. Some chloroplast-encoded proteins and enzymes of the Calvin pathway were detected under HT cultivation indicating regulation at the post-translational level. The carbon metabolic pathways investigated here in terms of proteomic changes provide new information, as well as validate data presented elsewhere with quantitative proteomics, adding to the existing knowledge of metabolism in E. gracilis. Putative functional annotations of several proteins that were previously unidentified are also provided.

AB - Euglena gracilis can use a wide range of organic carbon sources, as well as CO2 from the atmosphere. This metabolic versatility is owed to the genome of E. gracilis that can encode a wide range of enzymes. Many of these enzymes are regulated post-transcriptionally, allowing the cells to adapt quickly to changes in their surroundings. Here we investigated the effect of predominantly phototrophic (PT), mixotrophic (MT) and heterotrophic (HT) cultivation on central carbon metabolism in E. gracilis Z using label-free shotgun proteomics. Differential expression between isozymes was observed based on the cultivation condition. A hexokinase enzyme identified in the published transcriptome was not detected in the proteome. Instead, a high-specificity glucokinase appeared to conduct the first step of glycolysis. Two candidates for paramylon synthase were identified (EgGSL1 and EgGSL2), of which the predominant EgGSL2 protein was detected across all growth conditions, while EgGSL1 was only detected in the presence of light (PT and MT cultivations). Proteomic analysis revealed that the oxidative pentose phosphate pathway also plays a key role in glucose metabolism under MT and HT cultivation. Some chloroplast-encoded proteins and enzymes of the Calvin pathway were detected under HT cultivation indicating regulation at the post-translational level. The carbon metabolic pathways investigated here in terms of proteomic changes provide new information, as well as validate data presented elsewhere with quantitative proteomics, adding to the existing knowledge of metabolism in E. gracilis. Putative functional annotations of several proteins that were previously unidentified are also provided.

KW - Carbon metabolism

KW - Glucokinase

KW - Paramylon synthesis

KW - Post-transcriptional regulation

KW - Euglena gracilis proteomics

UR - http://www.scopus.com/inward/record.url?scp=85070522663&partnerID=8YFLogxK

UR - http://purl.org/au-research/grants/arc/IC130100009

U2 - 10.1016/j.algal.2019.101638

DO - 10.1016/j.algal.2019.101638

M3 - Article

VL - 43

JO - Algal Research

T2 - Algal Research

JF - Algal Research

SN - 2211-9264

M1 - 101638

ER -