The role of Rubisco kinetics and pyrenoid morphology in shaping the CCM of haptophyte microalgae
The haptophyte algae are a cosmopolitan group of primary producers that contribute significantly to the marine carbon cycle and play a major role in paleo-climate studies. Despite their global importance, little is known about carbon assimilation in haptophytes, in particular the kinetics of their F...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Journal article |
| Published: |
Oxford University Press
2017
|
| _version_ | 1797056772402315264 |
|---|---|
| author | Heureux, A Young, J Whitney, S Eason Hubbard, M Lee, R Sharwood, R Rickaby, R |
| author_facet | Heureux, A Young, J Whitney, S Eason Hubbard, M Lee, R Sharwood, R Rickaby, R |
| author_sort | Heureux, A |
| collection | OXFORD |
| description | The haptophyte algae are a cosmopolitan group of primary producers that contribute significantly to the marine carbon cycle and play a major role in paleo-climate studies. Despite their global importance, little is known about carbon assimilation in haptophytes, in particular the kinetics of their Form 1D CO2-fixing enzyme, Rubisco. Here we examine Rubisco properties of three haptophytes with a range of pyrenoid morphologies (Pleurochrysis carterae, Tisochrysis lutea, and Pavlova lutheri) and the diatom Phaeodactylum tricornutum that exhibit contrasting sensitivities to the trade-offs between substrate affinity (Km) and turnover rate (kcat) for both CO2 and O2. The pyrenoid-containing T. lutea and P. carterae showed lower Rubisco content and carboxylation properties (KC and kCcat) comparable with those of Form 1D-containing non-green algae. In contrast, the pyrenoid-lacking P. lutheri produced Rubisco in 3-fold higher amounts, and displayed a Form 1B Rubisco kCcat–KC relationship and increased CO2/O2 specificity that, when modeled in the context of a C3 leaf, supported equivalent rates of photosynthesis to higher plant Rubisco. Correlation between the differing Rubisco properties and the occurrence and localization of pyrenoids with differing intracellular CO2:O2 microenvironments has probably influenced the divergent evolution of Form 1B and 1D Rubisco kinetics. |
| first_indexed | 2024-03-06T19:27:12Z |
| format | Journal article |
| id | oxford-uuid:1c29e57b-2a75-41ad-afb2-f57d70d9fcfc |
| institution | University of Oxford |
| last_indexed | 2024-03-06T19:27:12Z |
| publishDate | 2017 |
| publisher | Oxford University Press |
| record_format | dspace |
| spelling | oxford-uuid:1c29e57b-2a75-41ad-afb2-f57d70d9fcfc2022-03-26T11:04:16ZThe role of Rubisco kinetics and pyrenoid morphology in shaping the CCM of haptophyte microalgaeJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:1c29e57b-2a75-41ad-afb2-f57d70d9fcfcSymplectic Elements at OxfordOxford University Press2017Heureux, AYoung, JWhitney, SEason Hubbard, MLee, RSharwood, RRickaby, RThe haptophyte algae are a cosmopolitan group of primary producers that contribute significantly to the marine carbon cycle and play a major role in paleo-climate studies. Despite their global importance, little is known about carbon assimilation in haptophytes, in particular the kinetics of their Form 1D CO2-fixing enzyme, Rubisco. Here we examine Rubisco properties of three haptophytes with a range of pyrenoid morphologies (Pleurochrysis carterae, Tisochrysis lutea, and Pavlova lutheri) and the diatom Phaeodactylum tricornutum that exhibit contrasting sensitivities to the trade-offs between substrate affinity (Km) and turnover rate (kcat) for both CO2 and O2. The pyrenoid-containing T. lutea and P. carterae showed lower Rubisco content and carboxylation properties (KC and kCcat) comparable with those of Form 1D-containing non-green algae. In contrast, the pyrenoid-lacking P. lutheri produced Rubisco in 3-fold higher amounts, and displayed a Form 1B Rubisco kCcat–KC relationship and increased CO2/O2 specificity that, when modeled in the context of a C3 leaf, supported equivalent rates of photosynthesis to higher plant Rubisco. Correlation between the differing Rubisco properties and the occurrence and localization of pyrenoids with differing intracellular CO2:O2 microenvironments has probably influenced the divergent evolution of Form 1B and 1D Rubisco kinetics. |
| spellingShingle | Heureux, A Young, J Whitney, S Eason Hubbard, M Lee, R Sharwood, R Rickaby, R The role of Rubisco kinetics and pyrenoid morphology in shaping the CCM of haptophyte microalgae |
| title | The role of Rubisco kinetics and pyrenoid morphology in shaping the CCM of haptophyte microalgae |
| title_full | The role of Rubisco kinetics and pyrenoid morphology in shaping the CCM of haptophyte microalgae |
| title_fullStr | The role of Rubisco kinetics and pyrenoid morphology in shaping the CCM of haptophyte microalgae |
| title_full_unstemmed | The role of Rubisco kinetics and pyrenoid morphology in shaping the CCM of haptophyte microalgae |
| title_short | The role of Rubisco kinetics and pyrenoid morphology in shaping the CCM of haptophyte microalgae |
| title_sort | role of rubisco kinetics and pyrenoid morphology in shaping the ccm of haptophyte microalgae |
| work_keys_str_mv | AT heureuxa theroleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT youngj theroleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT whitneys theroleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT easonhubbardm theroleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT leer theroleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT sharwoodr theroleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT rickabyr theroleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT heureuxa roleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT youngj roleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT whitneys roleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT easonhubbardm roleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT leer roleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT sharwoodr roleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae AT rickabyr roleofrubiscokineticsandpyrenoidmorphologyinshapingtheccmofhaptophytemicroalgae |