Structural-functional analysis of biopolymers and their complexes. The radius of gyration is an indicator of protein structure compactness. The study analyzed 3769 protein domains of four major classes (α, β, α/β, and α+β) and found that each class has a characteristic radius of gyration that determines the protein structure compactness. α-proteins have the highest radius of gyration, suggesting less tight packing compared to β- and (α+β)-proteins. α/β-proteins have the lowest radius of gyration and the tightest packing. The protein radius of gyration normalized by the radius of gyration of a ball with the same volume is independent of the protein size. The study also found that proteins with a three-state folding mechanism are more compact than those with a two-state mechanism. The folding rate decreases with increasing protein size, but statistical analysis showed a correlation of about 60% between folding rate and protein size. The study also found that contact order correlates with the folding rate, but only for similarly sized proteins folding via the two-state mechanism. The study found that α-helices provide a folding barrier, and the folding rate depends on the effective length of the nonhelical regions of a protein chain. The compactness of a protein is defined as the ratio of the accessible surface area of the protein to the surface area of an ideal sphere of the same volume. The study found that α/β-proteins are the most compact, while α-proteins are the loosest. The study also found that proteins with a three-state folding mechanism are more compact than those folding via the two-state mechanism. The study used the SCOP database to analyze the protein domains and found that there were 3769 protein domains belonging to the four major structural classes. The study also used a database of proteins with experimentally determined folding rates. The radius of gyration is a parameter that describes the equilibrium conformation of a total system and is computed in two steps. First, the coordinates of the center of mass are determined, and then the radius of gyration is calculated. The study found that the radius of gyration is independent of the protein size. The study also found that the radius of gyration normalized by the radius of gyration of a ball with the same volume is independent of the protein size. The study found that α/β-proteins are the most compact, while α-proteins are the loosest. The study also found that proteins with a three-state folding mechanism are more compact than those folding via the two-state mechanism.Structural-functional analysis of biopolymers and their complexes. The radius of gyration is an indicator of protein structure compactness. The study analyzed 3769 protein domains of four major classes (α, β, α/β, and α+β) and found that each class has a characteristic radius of gyration that determines the protein structure compactness. α-proteins have the highest radius of gyration, suggesting less tight packing compared to β- and (α+β)-proteins. α/β-proteins have the lowest radius of gyration and the tightest packing. The protein radius of gyration normalized by the radius of gyration of a ball with the same volume is independent of the protein size. The study also found that proteins with a three-state folding mechanism are more compact than those with a two-state mechanism. The folding rate decreases with increasing protein size, but statistical analysis showed a correlation of about 60% between folding rate and protein size. The study also found that contact order correlates with the folding rate, but only for similarly sized proteins folding via the two-state mechanism. The study found that α-helices provide a folding barrier, and the folding rate depends on the effective length of the nonhelical regions of a protein chain. The compactness of a protein is defined as the ratio of the accessible surface area of the protein to the surface area of an ideal sphere of the same volume. The study found that α/β-proteins are the most compact, while α-proteins are the loosest. The study also found that proteins with a three-state folding mechanism are more compact than those folding via the two-state mechanism. The study used the SCOP database to analyze the protein domains and found that there were 3769 protein domains belonging to the four major structural classes. The study also used a database of proteins with experimentally determined folding rates. The radius of gyration is a parameter that describes the equilibrium conformation of a total system and is computed in two steps. First, the coordinates of the center of mass are determined, and then the radius of gyration is calculated. The study found that the radius of gyration is independent of the protein size. The study also found that the radius of gyration normalized by the radius of gyration of a ball with the same volume is independent of the protein size. The study found that α/β-proteins are the most compact, while α-proteins are the loosest. The study also found that proteins with a three-state folding mechanism are more compact than those folding via the two-state mechanism.