5B5X

Crystal structure of limiting CO2-inducible protein LCIC

Summary for 5B5X

• Entry DOI: 10.2210/pdb5b5x/pdb
• Related: 5B5Y 5B5Z 5B60 5K5W
• Descriptor: limiting CO2-inducible protein LCIC, ZINC ION, SULFATE ION, ... (4 entities in total)
• Functional Keywords: metalloprotein, metal binding protein
• Biological source: Chlamydomonas reinhardtii
• Total number of polymer chains: 1
• Total formula weight: 33415.51

Authors

Jin, S.,Sun, J.,Wunder, T.,Tang, D.,Mueller-Cajar, O.M.,Gao, Y. (deposition date: 2016-05-24, release date: 2016-12-07, Last modification date: 2024-03-20)

Primary citation

Jin, S.,Sun, J.,Wunder, T.,Tang, D.,Cousins, A.B.,Sze, S.K.,Mueller-Cajar, O.,Gao, Y.G.
Structural insights into the LCIB protein family reveals a new group of beta-carbonic anhydrases
Proc. Natl. Acad. Sci. U.S.A., 113:14716-14721, 2016

PubMed Abstract: Aquatic microalgae have evolved diverse CO-concentrating mechanisms (CCMs) to saturate the carboxylase with its substrate, to compensate for the slow kinetics and competing oxygenation reaction of the key photosynthetic CO-fixing enzyme rubisco. The limiting CO-inducible B protein (LCIB) is known to be essential for CCM function in Chlamydomonas reinhardtii To assign a function to this previously uncharacterized protein family, we purified and characterized a phylogenetically diverse set of LCIB homologs. Three of the six homologs are functional carbonic anhydrases (CAs). We determined the crystal structures of LCIB and limiting CO-inducible C protein (LCIC) from C. reinhardtii and a CA-functional homolog from Phaeodactylum tricornutum, all of which harbor motifs bearing close resemblance to the active site of canonical β-CAs. Our results identify the LCIB family as a previously unidentified group of β-CAs, and provide a biochemical foundation for their function in the microalgal CCMs.

PubMed: 27911826
DOI: 10.1073/pnas.1616294113

Experimental method

X-RAY DIFFRACTION (2.511 Å)