Investigation of the Gracilaria gracilis proteome response to nitrogen limitation
type: CreativeWork
description: Gracilaria gracilis, a commercially important red macroalgal species found on the west coast of South Africa, is one of two Gracilaria species used in the production of hydrocolloid agar. In the past, commercial quantities of G. gracilis were harvested from Saldanha Bay until population collapses of the natural resource necessitated the need for research into alternative aquaculture programs for G. gracilis cultivation. One of the reasons for the G. gracilis population collapse was attributed to adverse conditions during summer which led to thermal stratification of the water column and subsequent nutrient limiting conditions. Inorganic nitrogen has been identified as the major nutrient factor limiting growth and production of G. gracilis populations in South Africa. Although the physiological mechanisms implemented by G. gracilis which allow adaption to low nitrogen environments have been investigated, not much is known about the molecular mechanisms which underlie these adaptions. Thus, it is necessary to elucidate the molecular basis of these adaptions in G. gracilis to complement the existing physiological data. In this study, a differential proteomics approach employing two-dimensional gel electrophoresis and liquid chromatography tandem mass spectrometry was used to investigate G. gracilis proteome changes in response to nitrogen limitation and recovery. Putative identities of 22 proteins that were changed significantly (P<O.05) in their abundance in response to nitrogen limitation and recovery were obtained. The identified proteins functioned in a range of biological processes including glycolysis, photosynthesis, A TP synthesis, galactose metabolism, protein-refolding and biosynthesis, nitrogen metabolism and cytoskeleton remodelling. A detailed discussion proposing the possible role(s) of each putative G. gracilis protein, along with the associated metabolic pathways activated or repressed in response to N stress, is provided. Fructose 1, 6 biphosphate aldo…
abstract: Gracilaria gracilis, a commercially important red macroalgal species found on the west coast of South Africa, is one of two Gracilaria species used in the production of hydrocolloid agar. In the past, commercial quantities of G. gracilis were harvested from Saldanha Bay until population collapses of the natural resource necessitated the need for research into alternative aquaculture programs for G. gracilis cultivation. One of the reasons for the G. gracilis population collapse was attributed to adverse conditions during summer which led to thermal stratification of the water column and subsequent nutrient limiting conditions. Inorganic nitrogen has been identified as the major nutrient factor limiting growth and production of G. gracilis populations in South Africa. Although the physiological mechanisms implemented by G. gracilis which allow adaption to low nitrogen environments have been investigated, not much is known about the molecular mechanisms which underlie these adaptions. Thus, it is necessary to elucidate the molecular basis of these adaptions in G. gracilis to complement the existing physiological data. In this study, a differential proteomics approach employing two-dimensional gel electrophoresis and liquid chromatography tandem mass spectrometry was used to investigate G. gracilis proteome changes in response to nitrogen limitation and recovery. Putative identities of 22 proteins that were changed significantly (P<O.05) in their abundance in response to nitrogen limitation and recovery were obtained. The identified proteins functioned in a range of biological processes including glycolysis, photosynthesis, A TP synthesis, galactose metabolism, protein-refolding and biosynthesis, nitrogen metabolism and cytoskeleton remodelling. A detailed discussion proposing the possible role(s) of each putative G. gracilis protein, along with the associated metabolic pathways activated or repressed in response to N stress, is provided. Fructose 1, 6 biphosphate aldo…
author: Naidoo, René Kathleen
language: eng
date published: 2012
date modified: 2026-07-22T22:22:52Z
provider: University of Cape Town
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Department of Molecular and Cell Biology

PropertyValue
property ID: Handle
value: http://hdl.handle.net/11427/13095