The quaternary structure of ABC transporters is a highly debated question, since higher oligomeric states than the minimal functional unit (i.e. two TMDs plus two NBDs) have been reported for various ABC transporters, including CFTR [60], [61], [62], [63], BCRP [64], [65], [66], [67] or ABCA1 [68] (for a recent review see [69]).
Lukin, J.A. et al. Quaternary structure of hemoglobin in solution.
Hence, it is unlikely that viral quaternary structure evolves merely to evade immune recognition.
Biasini, M. et al. SWISS-MODEL: modelling protein tertiary and quaternary structure using evolutionary information.
The nature of the quaternary structure is demonstrated by the structure of hemoglobin.
Biasini M, Bienert S, Waterhouse A et al. SWISS-MODEL: Modelling protein tertiary and quaternary structure using evolutionary information.
However, often a fourth level is needed to describe the final protein's structure; this level is called quaternary structure.
Denaturation is a loss of structure and function in proteins through disruption of the network of noncovalent interactions, which maintain secondary, tertiary and quaternary structure.
The catchments studied are located in regions with minimal Quaternary tectonic activity and span different climates over 12o latitude.
Here, we demonstrate quaternary structure determination in biological samples using a combination of chemical cross-linking, high-resolution mass spectrometry and high-accuracy protein structure modeling.
