4o2x

Structure of a malarial proteinStructure of a malarial protein

Structural highlights 4o2x is a 2 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function [MALE_ECOLI] Involved in the high-affinity maltose membrane transport system MalEFGK. Initial receptor for the active transport of and chemotaxis toward maltooligosaccharides. Publication Abstract from PubMed The N-end rule pathway uses an evolutionarily conserved mechanism in bacteria and eukaryotes that marks proteins for degradation by ATP-dependent chaperones and proteases such as the Clp chaperones and proteases. Specific N-terminal amino acids (N-degrons) are sufficient to target substrates for degradation. In bacteria, the ClpS adaptor binds and delivers N-end rule substrates for their degradation upon association with the ClpA/P chaperone/protease. Here, we report the first crystal structure, solved at 2.7 A resolution, of a eukaryotic homolog of bacterial ClpS from the malaria apicomplexan parasite Plasmodium falciparum (Pfal). Despite limited sequence identity, Plasmodium ClpS is very similar to bacterial ClpS. Akin to its bacterial orthologs, plasmodial ClpS harbors a preformed hydrophobic pocket whose geometry and chemical properties are compatible with the binding of N-degrons. However, while the N-degron binding pocket in bacterial ClpS structures is open and accessible, the corresponding pocket in Plasmodium ClpS is occluded by a conserved surface loop that acts as a latch. Despite the closed conformation observed in the crystal, we show that, in solution, Pfal-ClpS binds and discriminates peptides mimicking bona fide N-end rule substrates. The presence of an apicoplast targeting peptide suggests that Pfal-ClpS localizes to this plastid-like organelle characteristic of all Apicomplexa and hosting most of its Clp machinery. By analogy with the related ClpS1 from plant chloroplasts and cyanobacteria, Plasmodium ClpS likely functions in association with ClpC in the apicoplast. Our findings open new venues for the design of novel anti-malarial drugs aimed at disrupting parasite-specific protein quality control pathways. Structure of a putative ClpS N-end rule adaptor protein from the malaria pathogen Plasmodium falciparum.,AhYoung AP, Koehl A, Vizcarra CL, Cascio D, Egea PF Protein Sci. 2016 Mar;25(3):689-701. doi: 10.1002/pro.2868. Epub 2016 Jan 13. PMID:26701219 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 4o2x, resolution 2.70Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image