Cargando…

Characterization of a Functional Role of the Bradyrhizobium japonicum Isocitrate Lyase in Desiccation Tolerance

Bradyrhizobium japonicum is a nitrogen-fixing symbiont of soybean. In previous studies, transcriptomic profiling of B. japonicum USDA110, grown under various environmental conditions, revealed the highly induced gene aceA, encoding isocitrate lyase (ICL). The ICL catalyzes the conversion of isocitra...

Descripción completa

Detalles Bibliográficos
Autores principales: Jeon, Jeong-Min, Lee, Hae-In, Sadowsky, Michael J., Sugawara, Masayuki, Chang, Woo-Suk
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4519974/
https://www.ncbi.nlm.nih.gov/pubmed/26204840
http://dx.doi.org/10.3390/ijms160716695
_version_ 1782383591284539392
author Jeon, Jeong-Min
Lee, Hae-In
Sadowsky, Michael J.
Sugawara, Masayuki
Chang, Woo-Suk
author_facet Jeon, Jeong-Min
Lee, Hae-In
Sadowsky, Michael J.
Sugawara, Masayuki
Chang, Woo-Suk
author_sort Jeon, Jeong-Min
collection PubMed
description Bradyrhizobium japonicum is a nitrogen-fixing symbiont of soybean. In previous studies, transcriptomic profiling of B. japonicum USDA110, grown under various environmental conditions, revealed the highly induced gene aceA, encoding isocitrate lyase (ICL). The ICL catalyzes the conversion of isocitrate to succinate and glyoxylate in the glyoxylate bypass of the TCA cycle. Here, we evaluated the functional role of B. japonicum ICL under desiccation-induced stress conditions. We purified AceA (molecular mass = 65 kDa) from B. japonicum USDA110, using a His-tag and Ni-NTA column approach, and confirmed its ICL enzyme activity. The aceA mutant showed higher sensitivity to desiccation stress (27% relative humidity (RH)), compared to the wild type. ICL activity of the wild type strain increased approximately 2.5-fold upon exposure to 27% RH for 24 h. The aceA mutant also showed an increased susceptibility to salt stress. Gene expression analysis of aceA using qRT-PCR revealed a 148-fold induction by desiccation, while other genes involved in the glyoxylate pathway were not differentially expressed in this condition. Transcriptome analyses revealed that stress-related genes, such as chaperones, were upregulated in the wild-type under desiccating conditions, even though fold induction was not dramatic (ca. 1.5–2.5-fold).
format Online
Article
Text
id pubmed-4519974
institution National Center for Biotechnology Information
language English
publishDate 2015
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-45199742015-08-03 Characterization of a Functional Role of the Bradyrhizobium japonicum Isocitrate Lyase in Desiccation Tolerance Jeon, Jeong-Min Lee, Hae-In Sadowsky, Michael J. Sugawara, Masayuki Chang, Woo-Suk Int J Mol Sci Article Bradyrhizobium japonicum is a nitrogen-fixing symbiont of soybean. In previous studies, transcriptomic profiling of B. japonicum USDA110, grown under various environmental conditions, revealed the highly induced gene aceA, encoding isocitrate lyase (ICL). The ICL catalyzes the conversion of isocitrate to succinate and glyoxylate in the glyoxylate bypass of the TCA cycle. Here, we evaluated the functional role of B. japonicum ICL under desiccation-induced stress conditions. We purified AceA (molecular mass = 65 kDa) from B. japonicum USDA110, using a His-tag and Ni-NTA column approach, and confirmed its ICL enzyme activity. The aceA mutant showed higher sensitivity to desiccation stress (27% relative humidity (RH)), compared to the wild type. ICL activity of the wild type strain increased approximately 2.5-fold upon exposure to 27% RH for 24 h. The aceA mutant also showed an increased susceptibility to salt stress. Gene expression analysis of aceA using qRT-PCR revealed a 148-fold induction by desiccation, while other genes involved in the glyoxylate pathway were not differentially expressed in this condition. Transcriptome analyses revealed that stress-related genes, such as chaperones, were upregulated in the wild-type under desiccating conditions, even though fold induction was not dramatic (ca. 1.5–2.5-fold). MDPI 2015-07-22 /pmc/articles/PMC4519974/ /pubmed/26204840 http://dx.doi.org/10.3390/ijms160716695 Text en © 2015 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Jeon, Jeong-Min
Lee, Hae-In
Sadowsky, Michael J.
Sugawara, Masayuki
Chang, Woo-Suk
Characterization of a Functional Role of the Bradyrhizobium japonicum Isocitrate Lyase in Desiccation Tolerance
title Characterization of a Functional Role of the Bradyrhizobium japonicum Isocitrate Lyase in Desiccation Tolerance
title_full Characterization of a Functional Role of the Bradyrhizobium japonicum Isocitrate Lyase in Desiccation Tolerance
title_fullStr Characterization of a Functional Role of the Bradyrhizobium japonicum Isocitrate Lyase in Desiccation Tolerance
title_full_unstemmed Characterization of a Functional Role of the Bradyrhizobium japonicum Isocitrate Lyase in Desiccation Tolerance
title_short Characterization of a Functional Role of the Bradyrhizobium japonicum Isocitrate Lyase in Desiccation Tolerance
title_sort characterization of a functional role of the bradyrhizobium japonicum isocitrate lyase in desiccation tolerance
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4519974/
https://www.ncbi.nlm.nih.gov/pubmed/26204840
http://dx.doi.org/10.3390/ijms160716695
work_keys_str_mv AT jeonjeongmin characterizationofafunctionalroleofthebradyrhizobiumjaponicumisocitratelyaseindesiccationtolerance
AT leehaein characterizationofafunctionalroleofthebradyrhizobiumjaponicumisocitratelyaseindesiccationtolerance
AT sadowskymichaelj characterizationofafunctionalroleofthebradyrhizobiumjaponicumisocitratelyaseindesiccationtolerance
AT sugawaramasayuki characterizationofafunctionalroleofthebradyrhizobiumjaponicumisocitratelyaseindesiccationtolerance
AT changwoosuk characterizationofafunctionalroleofthebradyrhizobiumjaponicumisocitratelyaseindesiccationtolerance