"000336643800002" . "Moody, NR" . . . "RIV/60461373:22340/14:43897069" . "The N-terminus of the B-chain of insulin may adopt two alternative conformations designated as the T- and R-states. Despite the recent structural insight into insulin-insulin receptor (IR) complexes, the physiological relevance of the T/R transition is still unclear. Hence, this study focused on the rational design, synthesis, and characterization of human insulin analogues structurally locked in expected R- or T-states. Sites B3, B5, and B8, capable of affecting the conformation of the N-terminus of the B-chain, were subjects of rational substitutions with amino acids with specific allowed and disallowed dihedral phi and psi main-chain angles. alpha-Aminoisobutyric acid was systematically incorporated into positions B3, B5, and B8 for stabilization of the R-state, and N-methylalanine and D-proline amino acids were introduced at position B8 for stabilization of the T-state. IR affinities of the analogues were compared and correlated with their T/R transition ability and analyzed against their crystal and nuclear magnetic resonance structures. Our data revealed that (i) the T-like state is indeed important for the folding efficiency of (pro)insulin, (ii) the R-state is most probably incompatible with an active form of insulin, (iii) the R-state cannot be induced or stabilized by a single substitution at a specific site, and (iv) the B1-B8 segment is capable of folding into a variety of low-affinity T-like states. Therefore, we conclude that the active conformation of the N-terminus of the B-chain must be different from the %22classical%22 T-state and that a substantial flexibility of the B1-B8 segment, where GlyB8 plays a key role, is a crucial prerequisite for an efficient insulin-IR interaction." . . . "53" . "0006-2960" . . . . "Turkenburg, J. P." . "Urbanov\u00E1, Marie" . "22340" . . "Insight into the Structural and Biological Relevance of the T/R Transition of the N-Terminus of the B-Chain in Human Insulin" . "RIV/60461373:22340/14:43897069!RIV15-GA0-22340___" . . "Veverka, V\u00E1clav" . . . . "I, P(GAP208/11/0105), P(GPP207/11/P430), P(LK11205), S" . "2"^^ . "Kosinov\u00E1, Lucie" . . . . . "Novotn\u00E1, Pavl\u00EDna" . "21" . . "Brzozowski, Andrzej" . "Collinsov\u00E1, Michaela" . . . "10.1021/bi500073z" . "10"^^ . . "Biochemistry" . "US - Spojen\u00E9 st\u00E1ty americk\u00E9" . "22041" . . "[0B1123BE7C67]" . "PHENOL; STABILITY; PROTEIN; ANALOGS; HEXAMER; LIGAND-BINDING; ANGSTROM RESOLUTION; ACTIVE CONFORMATION; MACROMOLECULAR STRUCTURES; RECEPTOR-BINDING REGION"@en . . . "Insight into the Structural and Biological Relevance of the T/R Transition of the N-Terminus of the B-Chain in Human Insulin"@en . "Insight into the Structural and Biological Relevance of the T/R Transition of the N-Terminus of the B-Chain in Human Insulin"@en . "11"^^ . . "\u017D\u00E1kov\u00E1, Lenka" . . . "Insight into the Structural and Biological Relevance of the T/R Transition of the N-Terminus of the B-Chain in Human Insulin" . "The N-terminus of the B-chain of insulin may adopt two alternative conformations designated as the T- and R-states. Despite the recent structural insight into insulin-insulin receptor (IR) complexes, the physiological relevance of the T/R transition is still unclear. Hence, this study focused on the rational design, synthesis, and characterization of human insulin analogues structurally locked in expected R- or T-states. Sites B3, B5, and B8, capable of affecting the conformation of the N-terminus of the B-chain, were subjects of rational substitutions with amino acids with specific allowed and disallowed dihedral phi and psi main-chain angles. alpha-Aminoisobutyric acid was systematically incorporated into positions B3, B5, and B8 for stabilization of the R-state, and N-methylalanine and D-proline amino acids were introduced at position B8 for stabilization of the T-state. IR affinities of the analogues were compared and correlated with their T/R transition ability and analyzed against their crystal and nuclear magnetic resonance structures. Our data revealed that (i) the T-like state is indeed important for the folding efficiency of (pro)insulin, (ii) the R-state is most probably incompatible with an active form of insulin, (iii) the R-state cannot be induced or stabilized by a single substitution at a specific site, and (iv) the B1-B8 segment is capable of folding into a variety of low-affinity T-like states. Therefore, we conclude that the active conformation of the N-terminus of the B-chain must be different from the %22classical%22 T-state and that a substantial flexibility of the B1-B8 segment, where GlyB8 plays a key role, is a crucial prerequisite for an efficient insulin-IR interaction."@en . "Jir\u00E1\u010Dek, Ji\u0159\u00ED" . .