Morphological and Physiological Studies of the Carbon Concentrating Mechanism in Chlamydomonas reinhardtii

Chlamydomonas reinhardtii possesses a single-cell-based CO2-concentrating mechanism (CCM). The CCM is an important element of algal photosynthesis, metabolism, growth and biomass production, which works by increasing the concentration of inorganic carbon (Ci) in the pyrenoid, a dense RuBisCO-packed structure within the chloroplast. This suppresses RuBisCO oxygenase activity and associated photorespiration. The enhanced efficiency of CO2 assimilation in the pyrenoid via CCM had been modelled theoretically as a requirement for successful CCM in higher plant systems. The ultimate aim of my research is to understand the biogenesis of the pyrenoid using a set of CCM mutants with pyrenoidal defects. Immunofluorescence methods and spot growth tests under different CO2 concentrations were performed on mutants with CCM defects generated by an insertional mutagenesis screen. Morphological and physiological characterisation of these mutants revealed differences in the pyrenoid morphology, the ability for RuBisCO to aggregate into the pyrenoid and the formation of thylakoidal tubule network associated with the pyrenoid. The thylakoid tubule network may be linked to the transport of inorganic carbon into the pyrenoid as part of the CCM. Further characterisation of one of the mutants gave rise to the hypothesis that the gene of interest, Cre11.g467712 (SAGA), is a multi-functional anchor protein related to the structural formation of the pyrenoid and may be another essential component of the pyrenoid.

Name dc:type.qualificationname

Doctor of Philosophy (PhD)

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

University of Cambridge

Year dc:date.issued

2019

Author dc:creator

• Chan, Kher Xing

Advisor dc:contributor.advisor

• Griffiths, Howard

• Chlamydomonas reinhardtii
• Carbon concentrating mechanism
• Green alga
• pyrenoid
• Thylakoid tubule network
• CO2
• carbon dioxide
• single-cell CCM
• CCM
• Rubisco
• Immunofluorescence
• Electron microscopy
• Immunogold labelling
• Western blotting
• Proteomics
• Microscopy

Licence

• https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/f229e8a3-123f-471b-b507-2906b2a8ab21/download
• https://www.rioxx.net/licenses/all-rights-reserved/

Language dc:language

en

Author Identifier

0000-0002-0236-6378

OAI identifier oai:identifier

oai:www.repository.cam.ac.uk:1810/276829