In contrast to the antiparallel folds, the propeller fold (parallel stranded) featured an intense peak at ∼264 nm and a negative peak at 240 nm.
In the dimer, the two α subunits interact via β strands from propeller blades W7 and W8, forming an extended β sheet network.
French aviation pioneer Alphonse Penaud was the first to produce an inherently stable aircraft, the Planophore (1871), which featured a pusher propeller powered by twisted rubber strands.
In E. coli, Pal binds to a β-strand from the propeller structure of the protein TolB, through an "induced fit": a short segment in helix 3 of Pal is unwound and reforms as a β-structure paired with the TolB β-propeller [61].
In particular, the beta strands in the propeller folds never have an interleave >3, which means that full SMURF, as we know, is tractable on these folds.
In order to localize the position of the six small loops switching strands in beta propeller surrounding the active site, we analyzed PON1mut trajectories of MD simulations using PyMol viewer (Fig. 11).
In the RACK1 structure each propeller blade consists of a four-stranded antiparallel β-sheet, where strand A lines the central canal of the protein, and strand D is present on the outer circumference.
Each propeller blade consists of a four-stranded antiparallel β-sheet, where strand A lines the central canal of the protein, a channel of ~9 Å width, and strand D is presented on the outer circumference.
Structural modelling of the Nek8 RCC1-like domain reveals that H425 lies within a conserved motif that is commonly found in the loop between the third and fourth β-strands of RCC1-like propeller blades (Fig. 8B).
For example, the opening residue in β-strand A that lies proximal to the B-C turn is almost invariably valine or isoleucine and fits into the space between the B- and C-strands of the preceding propeller blade, directly behind the P-0 aspartic acid of the B-C turn on that blade and regulating inter-blade spacing at that point.
