Recombinant Escherichia coli Protein translocase subunit SecA (secA), partial

1. SecA cotranslationally recognizes the nascent chain of an inner membrane protein, RodZ, with high affinity and specificity and SecA is necessary and sufficient to direct the targeting and translocation of RodZ to the bacterial plasma membrane. PMID: 28928132
2. Both the preprotein mature domain targeting signals (MTSs) and their receptor site on SecA are essential for protein secretion. PMID: 28404644
3. SecA gains access to the SecYEG complex via a lipid-bound intermediate state, whereas acidic phospholipids allosterically activate SecA for ATP-dependent protein translocation. PMID: 27613865
4. Moreover, biphasic responses of inhibition of ion current and protein translocation activities were observed for many PrlA/SecY and PrlG/SecE suppressor membranes, with a low IC50 value similar to that of the SecA-only channels and a very high IC50. However, the suppressor strains are as sensitive to the inhibitor as the parental strain, suggesting that SecA-only channels have some essential physiological function(s) in t PMID: 27856243
5. A single conserved SecA signal peptide-binding site was identified in the two-helix finger subdomain of SecA. PMID: 26854513
6. Such lipid enrichment was not found with separately extracted SecDFyajC or YidC, which demonstrates a specific interaction between SecYEG and negatively charged lipids. PMID: 26129641
7. The model of interactions presented suggests a way that binding between SecA and SecB might decrease the affinity of precursor polypeptides for SecB and facilitate the transfer to SecA. PMID: 25534082
8. SecA defects are accompanied by dysregulation of MukB, gyrB, chromosome partitioning and DNA superhelicity. PMID: 24858081
9. The first small helix, the linker and part of the second helix (Delta2-22) were dispensable for SecA activity in complementing the growth of a SecA ts mutant. However, deletions of N-terminal residues 23-25 resulted in progressive retardation of growth. PMID: 25264203
10. Study shows that SecA moves polypeptides through the SecY channel by a "push and slide" mechanism. In its ATP-bound state, SecA interacts through a two-helix finger with a subset of amino acids in a substrate, pushing them into the channel. PMID: 24906156
11. this study identified the N-terminal helix of SecA required for a stable association with the ribosome. The structures indicate a possible function of the dimeric form of SecA at the ribosome. PMID: 24443566
12. Data suggest that YidC, SecE, and SecA are involved in membrane insertion of M13 procoat lep protein. PMID: 24275657
13. The amino terminus in the nucleotide binding domain (residues 2 to 11), Phe263 in the preprotein binding domain, and Tyr794 and Arg805 in the intramolecular regulator of the ATPase 1 domain were identified to be involved in ecSecA dimerization. PMID: 23585536
14. model for protein translocation, in which the mobility of the PPXD (pre-protein cross-linking domain) facilitates the transfer of pre-protein from SecA to SecYEG PMID: 23126322
15. The observed conformational changes thus position SecA for productive interaction with the SecYEG translocon and for transfer of segments of its passenger protein across the translocon PMID: 22304380
16. SecA can promote protein translocation and ion channel activities both when it is bound to lipids at low affinity sites and when it is bound to SecYEG with high affinity. PMID: 22033925
17. The authors found that signal peptide mutations that alter targeting kinetics and insertions or deletions that change the distance between the SecM signal peptide and the arrest motif perturb the regulation of SecA synthesis. PMID: 21635582
18. preprotein translocation, the two SecA protomers are different in structure and may play different roles. PMID: 21304597
19. Data show that FtsY, the bacterial SRalpha homologue, binds to the exposed C4/C5 loops of SecY, the central component of the bacterial Sec translocon, and that the same loops serve also as binding sites for SecA and the ribosome. PMID: 21255212
20. The dimeric state of SecA is required for protein translocation. PMID: 21397193
21. Data indicate that the SecA loop region populates a predominantly flexible state, even in the presence of structuring agent. PMID: 21337475
22. report a specific interaction between SecA and the ribosome at a site near the polypeptide exit channel PMID: 21292166
23. Results indicate that the presence of preprotein introduces asymmetry into translocation intermediates, while SecA remains dimeric during the translocation process. PMID: 21104364
24. Demonstrated directly an interaction between the N-terminal residues 2 through 11 of SecA and the C-terminal 13 residues of SecB by isothermal titration calorimetry and analytical sedimentation velocity centrifugation. PMID: 20512970
25. Data suggest that precursor movement results predominantly from Brownian motion and that the SecA ATPase regulates pore accessibility. PMID: 19656854
26. Data report the solution NMR structure of a fragment corresponding to the C-terminal domain of Escherichia coli SecA PMID: 15488768
27. extreme terminal SecA residues are not essential for SecA catalysis and dimerization PMID: 15710424
28. a conserved glutamate residue in the Escherichia coli SecA ATPase does not play a key role in catalysis PMID: 15710614
29. binding between the two symmetric molecules is asymmetric and that the C-terminal alpha-helices of SecB bind in the interfacial region of the SecA dimer PMID: 15811382
30. The fluorescence spectral properties of the single tryptophans of SecA and their accessibility to quencher acrylamide reveal that SecA undergoes a conformational change resulting in a more compact structure upon ATP binding and binding to the SecYEG pore. PMID: 15850376
31. the positive charges at the n-region and the hydrophobic helical h-region are the selective features for recognition of signal sequences by SecA, and the signal peptide-binding site on SecA is not fully buried within its structure PMID: 16046390
32. dissociation of the SecA dimer is not an essential feature of the protein translocation reaction PMID: 16115882
33. cytosolic SecA participates in the selection of proteins for export by co-translationally binding to the signal sequences of non-membrane proteins and directing those nascent chains to the translocon. PMID: 16120599
34. signal recognition particle- and SecA-dependent multiple spanning membrane protein YidC becomes SecA-independent if the large periplasmic loop connecting transmembrane domains 1 and 2 is reduced to less than 30 amino acids PMID: 16186099
35. the preprotein binding domain of SecA is a preprotein receptor and a physical bridge connecting bound preproteins to the DEAD motor PMID: 16243836
36. SecB and SecA display twofold symmetry and yet the complex between the two is stabilized by contacts that are distributed asymmetrically, we identify a third distinct region of their interaction PMID: 16731972
37. Signal peptide increased oligomerization of soluble SecA and thereby the membrane binding of SecA, while ATP induced dissociation of SecA oligomer and inhibited the interaction of soluble SecA with membranes. PMID: 16756762
38. Plasticity and functional disorder-order folding transitions coupled to ligand binding provide control of the catalytic activation process and simple regulation of allosteric mechanisms. PMID: 16783375
39. the motor function of SecA is realized by ligand-activated ATPase engine and its HSD-mediated conversion into the mechanical work of preprotein translocation PMID: 17005557
40. C6 tail of SecY interacts with the working form of SecA, whereas C4-C5 loops may offer constitutive SecA-binding sites PMID: 17060619
41. Data demonstrate that allosteric regulation of SecA by magnesium binding involves a large conformational change to the SecA dimer, which exerts a strong influence on the turnover and affinity for ATP, as well as the affinity for ADP. PMID: 17416585
42. structural details of SecA on lipid layers; the pore structure is altered after transferring crystals to the SecB solution, indicating that the lipid-specific SecA structure has the SecB binding activity. PMID: 17419072
43. The conserved arginine 357 of SecY is essential for the initiation of SecA-dependent translocation only. PMID: 17433305
44. inversion of SecG is essential for cytosolic SecA-dependent stimulation of protein translocation PMID: 17704542
45. interaction with SecYEG simultaneously decreases the affinity of SecA for ATP and inhibitory magnesium, favouring a previously identified active state of the ATPase PMID: 17964601
46. Data show that SecA interconverts between two conformations in solution, suggesting a simple mechanism for polypeptide translocation. PMID: 18022369
47. Study conclude that SecA functions as a dimer in the membrane and dissociation into monomers is not necessary during protein translocation. PMID: 18065528
48. The studies showed that the nonessential carboxyl-terminal 70 residues of SecA play no role in its dimerization, while amino-terminal region of SecA from 8 to 11 has a role in SecA dimerization and in vivo function. PMID: 18723626
49. cryo-electron microscopy reveals that SecA dimerizes in a closed conformation in solution PMID: 18772144
50. Variants of SecA and of SecB that populate complexes were used to examine both the hydrolysis of ATP and the translocation of polypeptides. PMID: 18978043

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KEGG: ecj:JW0096

STRING: 316385.ECDH10B_0080