(13)C cross-polarization/magic angle spinning NMR studies of alpha-elastin preparations show retention of overall structure and reduction of mobility with a decreased number of cross-links.
High-resolution solid-state (13)C NMR spectra are presented for samples of alpha-elastin prepared from the aorta of normal and copper-deficient pigs. Chemical shifts of the various peaks indicate that both the normal and undercross-linked peptides have similar overall structures. However, (13)C T(1), (13)C T(1 rho), and (1)H T(1 rho) measurements indicate that the alpha-elastin peptides obtained from the abnormal elastic fibers samples exhibit altered mobilities, particularly in their side chains. Results from spectra taken with a range of contact times and from dipolar dephasing experiments are consistent with conclusions reached with the relaxation measurements. Namely, the loss of function associated with the undercross-linked sample is correlated to a small but measurable difference in relative mobility.
Kumashiro
K K
KK
Department of Chemistry, University of Hawaii at Manoa, 2545 The Mall, Honolulu, HI 96822, USA.
Kim
M S
MS
Kaczmarek
S E
SE
Sandberg
L B
LB
Boyd
C D
CD
D000818:Animals; D001704:Biopolymers / Q000737:chemistry / Q000302:isolation & purification; D002247:Carbon Isotopes; D003300:Copper / Q000172:deficiency; D003432:Cross-Linking Reagents; D004549:Elastin / Q000737:chemistry* / Q000302:isolation & purification; D066298:In Vitro Techniques; D009682:Magnetic Resonance Spectroscopy; D013552:Swine
D001704:Biopolymers; D002247:Carbon Isotopes; D003432:Cross-Linking Reagents; D003300:Copper; D004549:Elastin