TY - JOUR
T1 - Secondary structural features of modules M2 and M3 of barnase in solution by NMR experiment and distance geometry calculation
AU - Ikura, Teikichi
AU - Gō, Nobuhiro
AU - Kohda, Daisuke
AU - Inagaki, Fuyuhiko
AU - Yanagawa, Hiroshi
AU - Kawabata, Masuyo
AU - Kawabata, Shun‐ichiro ‐i
AU - Iwanaga, Sadaaki
AU - Noguti, Tosiyuki
AU - Gō, Mitiko
PY - 1993/8
Y1 - 1993/8
N2 - Proteins consist of structural units such as globular domains, secondary structures, and modules. Modules were originally defined by partitioning a globular domain into compact regions, each of which is a contiguous polypeptide segment having a compact conformation. Since modules show close correlations with the intron positions of genes, they are regarded as primordial polypeptide pieces encoded by exons and shuffled, leading to yield new combination of them in early biological evolution. Do modules maintain their native conformations in solution when they are excised at their boundaries? In order to find answers to this question, we have synthesized modules of barnase, one of the bacterial RNases, and studied the solution structures of modules M2 (amino acid residues 24–52) and M3 (52–73) by 2D NMR studies. Some local secondary structures, α‐helix, and β‐turns in M2 and β‐turns in M3, were observed in the modules at the similar positions to those in the intact barnase but the overall state seems to be in a mixture of random and native conformations. The present result shows that the excised modules have propensity to form similar secondary structures to those of the intact barnase. © 1993 Wiley‐Liss, Inc.
AB - Proteins consist of structural units such as globular domains, secondary structures, and modules. Modules were originally defined by partitioning a globular domain into compact regions, each of which is a contiguous polypeptide segment having a compact conformation. Since modules show close correlations with the intron positions of genes, they are regarded as primordial polypeptide pieces encoded by exons and shuffled, leading to yield new combination of them in early biological evolution. Do modules maintain their native conformations in solution when they are excised at their boundaries? In order to find answers to this question, we have synthesized modules of barnase, one of the bacterial RNases, and studied the solution structures of modules M2 (amino acid residues 24–52) and M3 (52–73) by 2D NMR studies. Some local secondary structures, α‐helix, and β‐turns in M2 and β‐turns in M3, were observed in the modules at the similar positions to those in the intact barnase but the overall state seems to be in a mixture of random and native conformations. The present result shows that the excised modules have propensity to form similar secondary structures to those of the intact barnase. © 1993 Wiley‐Liss, Inc.
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U2 - 10.1002/prot.340160404
DO - 10.1002/prot.340160404
M3 - Article
C2 - 8356030
AN - SCOPUS:0027295863
VL - 16
SP - 341
EP - 356
JO - Proteins: Structure, Function and Genetics
JF - Proteins: Structure, Function and Genetics
SN - 0887-3585
IS - 4
ER -