Functional Characterization of Cyanobacterial Glycolate Metabolic Pathway Genes in Arabidopsis thaliana

  • Oral Presentation
  • Plant Cell Biology and Biochemistry
  • 13 Jun 2018 12:50
  • FS-G01, UCD Agriculture and food science Centre
  • View all IPSAM abstracts

Misbah Bilal*
University College Dublin, Ireland
COMSATS Institute of Information Technology, Pakistan

Charilaos Yiotis
University College Dublin, Ireland

Joanna Kacprzyk
University College Dublin, Ireland

Raza Ahmad
COMSATS Institute of Information Technology, Pakistan

Bruce Osborne
University College Dublin, Ireland

*Presenting Author

Photorespiration is often regarded as an inefficient metabolic pathway that results in significant losses of carbon as CO2. Despite extensive investigations over several decades attempts improve crop productivity by reducing photorespiration have been unsuccessful largely because modification to the first reaction of the pathway the oxidation of ribulose 1, 5 bisphosphate has proved intractable. In recent years the focus has been on modifications that bypass some of the photorespiratory reactions through the introduction of novel prokaryotic genes that metabolise glycolate one of the first products of photorespiration. In the present study, genes corresponding to a novel cyanobacterial biochemical pathway for glycolate metabolism were transformed in chloroplasts of Arabidopsis thaliana. Independent A. thaliana homozygous transgenic lines expressing the genes glycolate dehydrogenase 1 (glcd1), hydroxyacid dehydrogenase (hdh), oxalate decarboxylase (oxc) and (hdh::oxc) were developed. Chimeric gene integration and stable expression were evaluated by genomic and RT-PCR, respectively. At least 5 lines from each transgenic line were selected for further morphological, biochemical and physiological characterization. The morphological parameters; rosette diameter, leaf area, bolt height, number of leaves per plant and total dry weight measurements indicated that plant productivity is enhanced in transgenic lines. Preliminary measurements also indicate that the transgenic lines have higher leaf photosynthesis rates in comparison to the wild type. Our results indicate that modifications to photorespiration through a partial, glycolate-related, bypass of photorespiration can lead to enhanced productivity and that the establishment of a complete decarboxylation pathway could lead to greater productivity increases.