Question

Describe some of the common protein structural motifs.

Short answer

Some common structural motifs in globular proteins are$\mathbf{\beta \alpha \beta }\mathbf{}\mathbf{motif}\mathbf{,}\mathbf{}\mathbf{\beta }\mathbf{}\mathbf{hairpin}\mathbf{}\mathbf{motifs}\mathbf{,}\mathbf{}\mathbf{\alpha \alpha }\mathbf{}\mathbf{motifs}\mathbf{,}\mathbf{}\mathbf{greek}\mathbf{}\mathbf{key}\mathbf{}\mathbf{motif}\mathbf{,}$etc.

Step-by-step solution

Protein structural motifs

Combining the secondary structural elements, such as α helices and β sheets, in a globular protein forms the supersecondary structuresormotifs of the protein.

βαβ motif

βαβ motifis the most common supersecondary structure, where an α helix joins two parallel β sheets.

β hairpin

β hairpinis another common supersecondary structure, where relatively tight reverse turns join the antiparallel β sheets.

αα motif

In this supersecondary structure, two successive antiparallel α helices connectwith their axis inclined. This connection allows the energetically favorable interactions in a coiled coil conformation.

Greek key motifs

In a greek key motif, a β hairpin folds over to form 4-stranded antiparallel β sheets.