| IED ID | IndEnz0002004597 |
| Enzyme Type ID | protease004597 |
| Protein Name |
Carboxysome assembly protein CcmM CcmM58 M58 Carbon dioxide concentrating mechanism protein CcmM Carboxysome shell associated protein CcmM |
| Gene Name | ccmM Synpcc7942_1423 |
| Organism | Synechococcus elongatus (strain PCC 7942 / FACHB-805) (Anacystis nidulans R2) |
| Taxonomic Lineage | cellular organisms Bacteria Terrabacteria group Cyanobacteria/Melainabacteria group Cyanobacteria Synechococcales Synechococcaceae Synechococcus Synechococcus elongatus Synechococcus elongatus (strain PCC 7942 / FACHB-805) (Anacystis nidulans R2) |
| Enzyme Sequence | MPSPTTVPVATAGRLAEPYIDPAAQVHAIASIIGDVRIAAGVRVAAGVSIRADEGAPFQVGKESILQEGAVIHGLEYGRVLGDDQADYSVWIGQRVAITHKALIHGPAYLGDDCFVGFRSTVFNARVGAGSVIMMHALVQDVEIPPGRYVPSGAIITTQQQADRLPEVRPEDREFARHIIGSPPVIVRSTPAATADFHSTPTPSPLRPSSSEATTVSAYNGQGRLSSEVITQVRSLLNQGYRIGTEHADKRRFRTSSWQPCAPIQSTNERQVLSELENCLSEHEGEYVRLLGIDTNTRSRVFEALIQRPDGSVPESLGSQPVAVASGGGRQSSYASVSGNLSAEVVNKVRNLLAQGYRIGTEHADKRRFRTSSWQSCAPIQSSNERQVLAELENCLSEHEGEYVRLLGIDTASRSRVFEALIQDPQGPVGSAKAAAAPVSSATPSSHSYTSNGSSSSDVAGQVRGLLAQGYRISAEVADKRRFQTSSWQSLPALSGQSEATVLPALESILQEHKGKYVRLIGIDPAARRRVAELLIQKP |
| Enzyme Length | 539 |
| Uniprot Accession Number | Q03513 |
| Absorption | |
| Active Site | |
| Activity Regulation | |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | |
| DNA Binding | |
| EC Number | |
| Enzyme Function | FUNCTION: Functions as a scaffold protein for the assembly of beta-carboxysomes, initiates carboxysome assembly by coalescing RuBisCO (ribulose bisphosphate carboxylase, rbcL-rbcS) (Probable) (PubMed:24267892). Produced as a full-length (M58) and a shorter form (M35); both forms are required for correct carboxysome assembly and growth (PubMed:20304968). The short form is more abundant (PubMed:17675289, PubMed:20304968, PubMed:28963440, PubMed:31048338). Despite its strong similarity to gamma-class carbonic anhydrase (CA) it does not have detectable CA activity (Ref.3). {ECO:0000269|PubMed:17675289, ECO:0000269|PubMed:20304968, ECO:0000269|PubMed:24267892, ECO:0000269|PubMed:28963440, ECO:0000269|PubMed:31048338, ECO:0000269|Ref.3, ECO:0000305|PubMed:17675289, ECO:0000305|PubMed:20304968}.; FUNCTION: [Isoform CcmM35]: The M35 isoform is able to condense RuBisCO into a liquid matrix; the presence of disulfide bonds in M35 reduces affinity for RuBisCO, while mutating all 4 Cys to Ser causes a 4-fold increase in doubling time, more than 15% increase in CO(2) requirement, and abnormal carboxysomes. {ECO:0000269|PubMed:30675061}.; FUNCTION: Beta-carboxysome assembly initiates when soluble RuBisCO is condensed into a liquid matrix in a pre-carboxysome by the RbcS-like domains of probably both CcmM58 and CcmM35. CcmN interacts with the N-terminus of CcmM58, and then recruits the CcmK2 major shell protein plus other less abundant CcmK proteins via CcmN's encapsulation peptide. Shell formation requires CcmK proteins and CcmO. CcmL caps the otherwise elongated carboxysome. Once fully encapsulated carboxysomes are formed, they migrate within the cell probably via interactions with the cytoskeleton. {ECO:0000269|PubMed:24267892, ECO:0000269|PubMed:28963440, ECO:0000269|PubMed:30675061}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | |
| nucleotide Binding | |
| Features | Alternative sequence (2); Beta strand (3); Chain (1); Compositional bias (1); Disulfide bond (2); Helix (3); Mutagenesis (5); Region (3); Repeat (3); Turn (2) |
| Keywords | 3D-structure;Alternative initiation;Bacterial microcompartment;Carbon dioxide fixation;Carboxysome;Direct protein sequencing;Disulfide bond;Photosynthesis;Reference proteome;Repeat |
| Interact With | |
| Induction | INDUCTION: Carboxysome size and components vary with growth conditions. When grown in ambient air at medium light (50 uE meter(-2) second(-1)) there are 719 units (both forms are included in this measure) of this protein per carboxysome, the numbers decrease under low light and high CO(2), and increase under high light (at protein level). {ECO:0000269|PubMed:31048338}. |
| Subcellular Location | SUBCELLULAR LOCATION: Carboxysome {ECO:0000269|PubMed:17675289, ECO:0000269|PubMed:20304968, ECO:0000269|PubMed:28616951, ECO:0000269|PubMed:31048338, ECO:0000269|Ref.4}. Note=This cyanobacterium makes beta-type carboxysomes (Ref.4). Both isoforms are found equally distributed in the interior of the carboxysome (PubMed:28963440). {ECO:0000269|PubMed:28963440, ECO:0000269|Ref.4}. |
| Modified Residue | |
| Post Translational Modification | PTM: Identified as 2 proteins of 58 and 38 kDa by mass spectrometry, called M58 and M35, the shorter protein is translated starting at Val-216. Protease inhibitors do not alter the appearance of M35 (Ref.4, PubMed:20304968). In isolated carboxysomes M35 is 4-5 fold more abundant. The first amino acid (equivalent to Val-216) is not seen in Edman degradation, while Tyr-219 and Gln-222 may be post-translationally modified (PubMed:17675289). {ECO:0000269|PubMed:17675289, ECO:0000269|PubMed:20304968, ECO:0000269|Ref.4}. |
| Signal Peptide | |
| Structure 3D | Electron microscopy (1); X-ray crystallography (3) |
| Cross Reference PDB | 6HBA; 6HBB; 6HBC; 7D6C; |
| Mapped Pubmed ID | 33928692; |
| Motif | |
| Gene Encoded By | |
| Mass | 57,833 |
| Kinetics | |
| Metal Binding | |
| Rhea ID | |
| Cross Reference Brenda |