6T4H
Crystal structure of the accessory translocation ATPase, SecA2, from Clostridium difficile, in complex with adenosine-5'-(gamma-thio)-triphosphate
Summary for 6T4H
Entry DOI | 10.2210/pdb6t4h/pdb |
Descriptor | Protein translocase subunit SecA 2, PHOSPHOTHIOPHOSPHORIC ACID-ADENYLATE ESTER (3 entities in total) |
Functional Keywords | seca2, atpase, pathogenesis, protein transport |
Biological source | Peptoclostridium difficile (strain 630) |
Total number of polymer chains | 1 |
Total formula weight | 89770.00 |
Authors | Lindic, N.,Loboda, J.,Usenik, A.,Turk, D. (deposition date: 2019-10-14, release date: 2020-11-18, Last modification date: 2024-01-31) |
Primary citation | Lindic, N.,Loboda, J.,Usenik, A.,Vidmar, R.,Turk, D. The Structure of Clostridioides difficile SecA2 ATPase Exposes Regions Responsible for Differential Target Recognition of the SecA1 and SecA2-Dependent Systems. Int J Mol Sci, 21:-, 2020 Cited by PubMed Abstract: SecA protein is a major component of the general bacterial secretory system. It is an ATPase that couples nucleotide hydrolysis to protein translocation. In some Gram-positive pathogens, a second paralogue, SecA2, exports a different set of substrates, usually virulence factors. To identify SecA2 features different from SecA(1)s, we determined the crystal structure of SecA2 from , an important nosocomial pathogen, in apo and ATP-γ-S-bound form. The structure reveals a closed monomer lacking the C-terminal tail (CTT) with an otherwise similar multidomain organization to its SecA(1) homologues and conserved binding of ATP-γ-S. The average in vitro ATPase activity rate of SecA2 was 2.6 ± 0.1 µmolPi/min/µmol. Template-based modeling combined with evolutionary conservation analysis supports a model where SecA2 in open conformation binds the target protein, ensures its movement through the SecY channel, and enables dimerization through PPXD/HWD cross-interaction of monomers during the process. Both approaches exposed regions with differences between SecA(1) and SecA2 homologues, which are in agreement with the unique adaptation of SecA2 proteins for a specific type of substrate, a role that can be addressed in further studies. PubMed: 32858965DOI: 10.3390/ijms21176153 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (2.9 Å) |
Structure validation
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