期刊
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
卷 113, 期 35, 页码 9828-9833出版社
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1603112113
关键词
marine diatom; CGHR domain; luminal carbonic anhydrase; CO2-concentrating mechanism; pyrenoid
资金
- Japan Society for the Promotion of Science (JSPS) [24310015, 16H06557, 15K21531, 26870750, 15K16156]
- Science Research Promotion Fund Grant from the Japan Private School Promotion Foundation [g135011]
- MEXT-supported program for the Strategic Research Foundation for the Advancement of Environmental Protection Technology and for Development of Intelligent Self-Organized Biomaterials
- PMAC-supported Science Research Promotion Fund
- Grants-in-Aid for Scientific Research [15K16156, 16H06557, 15K21531, 26870750] Funding Source: KAKEN
The algal pyrenoid is a large plastid body, where the majority of the CO2-fixing enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) resides, and it is proposed to be the hub of the algal CO2-concentrating mechanism(CCM) and CO2 fixation. The thylakoid membrane is often in close proximity to or penetrates the pyrenoid itself, implying there is a functional cooperation between the pyrenoid and thylakoid. Here, GFP tagging and immunolocalization analyses revealed that a previously unidentified protein, Pt43233, is targeted to the lumen of the pyrenoid-penetrating thylakoid in the marine diatom Phaeodactylum tricornutum. The recombinant Pt43233 produced in Escherichia coli cells had both carbonic anhydrase (CA) and esterase activities. Furthermore, a Pt43233:GFP-fusion protein immunoprecipitated from P. tricornutum cells displayed a greater specific CA activity than detected for the purified recombinant protein. In an RNAi-generated Pt43233 knockdown mutant grown in atmospheric CO2 levels, photosynthetic dissolved inorganic carbon (DIC) affinity was decreased and growth was constantly retarded; in contrast, overexpression of Pt43233: GFP yielded a slightly greater photosynthetic DIC affinity. The discovery of a theta-type CA localized to the thylakoid lumen, with an essential role in photosynthetic efficiency and growth, strongly suggests the existence of a common role for the thylakoid-luminal CA with respect to the function of diverse algal pyrenoids.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据