Thesis (Ph.D.) - University of Warwick, 1999.
|Statement||Peter John Hynds.|
|The Physical Object|
|Number of Pages||222|
There is no evidence for a threshold level of Delta pH which is required to drive translocation of the kDa protein, Addition of uncouplers midway during import incubations results in a rapid and complete inhibition of translocation, showing that the continuous presence of the Delta pH is required for translocation to take place, During import into intact chloroplasts, the intermediate-size kDa protein substrate for the thylakoidal protein transport machinery . The delta pH‐driven and Sec‐related thylakoidal protein translocases recognise distinct types of thylakoid transfer signal, yet all transfer signals resemble bacterial signal peptides in structural by: The delta pH-driven and Sec-related thylakoidal protein translocases recognise distinct types of thylakoid transfer signal, yet all transfer signals resemble bacterial signal peptides in. 1. Introduction. Among the mechanisms catalyzing the transport of proteins across cellular membranes the Twin-arginine translocation (Tat) mechanism is distinguished by the fact that it can translocate proteins in a fully folded conformation [1,2].It is found operating at the cytoplasmic membranes of bacteria and archaea as well as at the thylakoid membranes of chloroplasts and their.
Abstract. The Delta pH-driven and Sec-related thylakoidal protein translocases recognise distinct types of thylakoid transfer signal, yet all transfer signals resemble bacterial signal peptides in structural terms, Comparison of known transfer signals reveals a single concrete difference: signals for the Delta pH-dependent system contain a common twin-arginine motif immediately before the. Membrane insertion is probably still reversible at this stage, and presumably driven by membrane-induced conformational changes. 45 (b) Lateral movement within the lipid bilayer of the membrane-inserted translocation intermediate to the TatB/C receptor complex, which probably corresponds to the kDa to kDa complexes described in the. The thylakoidal Tat translocation mechanism has been widely studied in vitro using well-established translocation assays. These assays have involved the incubation of intact chloroplasts or isolated thylakoids with in vitro -synthesized substrates, and the combined data have shown translocation by the thylakoid Tat system to be efficient. Among the protein translocation pathways of the thylakoid membrane in chloroplasts, the ΔpH/TAT pathway is unique in several aspects. In vitro transport assays with isolated chloroplasts or thylakoids have defined the trans-thylakoidal proton gradient as the sole requirement for effecting transport. From these studies, evidence has also.
S Brink, E Bogsch, W R Edwards, P J Hynds, C Robinson Targeting of thylakoid proteins by the Delta pH-driven twin-arginine translocation pathway requires a specific signal in the hydrophobic domain in conjunction with the twin-arginine motif. FEBS LETTERS 3. Ralf Bernd Klösgen's research works with 3, citations and 3, reads, including: Dual targeting of TatA points to a chloroplast-like Tat pathway in plant mitochondria. Protein translocation across biological membranes can expend a large portion of the total cellular metabolic energy. Although energy sources for this process have been well characterized, its total energy cost was unclear. Recently, this problem was addressed in the thylakoidal . A third thylakoid pathway is termed the Delta pH pathway because it employs the thylakoidal pH gradient as sole energy source for transport of lumenal proteins (Cline et al. ). The Delta pH pathway is responsible for transport of OE23, OE17, PSI-N, and PSII-T and exhibits several distinctive and unusual features.