cpSRP43 Is Both Highly Flexible and Stable: Structural Insights Using a Combined Experimental and Computational Approach

• DOI: 10.1021/acs.jcim.3c00319
• Publication Date: 2023-06-19T23:34:15Z
• Authors: Mitchell Benton; Mercede Furr; Vivek Govind Kumar; Adithya Polasa; Feng Gao; Colin David Heyes; Thallapuranam Kri...; Mahmoud Moradi
• Keywords: Microsecond

The novel multidomain protein, cpSRP43, is a unique subunit of the post-translational chloroplast signal recognition particle (cpSRP) targeting pathway in higher plants. cpSRP responsible for and insertion light-harvesting chlorophyll a/b binding proteins (LHCPs) to thylakoid membrane. Upon emergence into stroma, LHCPs form soluble transit complex with heterodimer, which composed cpSRP43 cpSRP54. irreplaceable as chaperone their translocation membrane remarkable its ability dissolve aggregates without need external energy input. In previous studies, has demonstrated significant flexibility interdomain dynamics. this study, we explore structural stability using combination computational experimental techniques find that protein concurrently highly stable flexible. addition microsecond-level unbiased molecular dynamics (MD), biased MD simulations based on system-specific collective variables are used along biophysical experimentation explain basis showing free cpSRP54-bound substantially different conformations conformational