TY - JOUR
T1 - Analysis of the stabilization of hen lysozyme by helix macrodipole and charged side chain interaction
AU - Motoshima, Hiroyuki
AU - Mine, Shouhei
AU - Masumoto, Kiyonari
AU - Abe, Yoshito
AU - Iwashita, Hiroki
AU - Hashimoto, Yoshio
AU - Chijiiwa, Yuki
AU - Ueda, Tadashi
AU - Imoto, Taiji
PY - 1997/6
Y1 - 1997/6
N2 - In the N-terminal region of the α-helix of the c-type lysozymes, two Asx residues exist at the 18th and 27th positions. Hen lysozyme has Asp18/Asn27 (18D/27N), and we prepared three mutant lysozymes, Asn18/Asn27 (18N/27N), Asn18/Asp27 (18N/27D), and Asp18/Asp27 (18D/27D). The stability of the wild-type (18D/27N) lysozyme supported the existence of a hydrogen bond between the side chain of Asp18 and the amide group at the N1 position in the α-helix, while the stability of the 18N/27D lysozyme supported the presence of the capping box between the Ser24 (N-cap) and Asp27 residues. Although electrostatic repulsion was observed between Asp18 and Asp27 residues in 18D/27D lysozyme, the dissociation of each residue contributed to stabilizing the B-helix in 18D/27D lysozyme through hydrogen bonding and charge-helix macrodipole interaction. This is the first evidence that two neighboring negative charges at the N-terminus of the helix both increased the stability of the protein.
AB - In the N-terminal region of the α-helix of the c-type lysozymes, two Asx residues exist at the 18th and 27th positions. Hen lysozyme has Asp18/Asn27 (18D/27N), and we prepared three mutant lysozymes, Asn18/Asn27 (18N/27N), Asn18/Asp27 (18N/27D), and Asp18/Asp27 (18D/27D). The stability of the wild-type (18D/27N) lysozyme supported the existence of a hydrogen bond between the side chain of Asp18 and the amide group at the N1 position in the α-helix, while the stability of the 18N/27D lysozyme supported the presence of the capping box between the Ser24 (N-cap) and Asp27 residues. Although electrostatic repulsion was observed between Asp18 and Asp27 residues in 18D/27D lysozyme, the dissociation of each residue contributed to stabilizing the B-helix in 18D/27D lysozyme through hydrogen bonding and charge-helix macrodipole interaction. This is the first evidence that two neighboring negative charges at the N-terminus of the helix both increased the stability of the protein.
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U2 - 10.1093/oxfordjournals.jbchem.a021697
DO - 10.1093/oxfordjournals.jbchem.a021697
M3 - Article
C2 - 9354379
AN - SCOPUS:0030760773
VL - 121
SP - 1076
EP - 1081
JO - Journal of Biochemistry
JF - Journal of Biochemistry
SN - 0021-924X
IS - 6
ER -