Table 1: 14 N (at 28.9 MHz) and 17O (at 48.8 MHz) linewidths, , of protein amino acids in different ionization states*a.

Amino AcidMWf , Hzb,c
pH 0.5pH 6.0
14N17O14N17O

Gly75.0755 (67)205 (233)36 (40)132 (131)
Ala89.1071 (79)276 (274)45 (49)194 (172)
Sar89.1083 (80)272 (274)60 (49)170 (172)
N,N-dimethyl-Gly103.10329 (314)198 (212)
Ser105.0997 (94)359 (320)57 (58)249 (218)
Pro115.1387 (104)286 (349)60 (64)197 (247)
Val117.15102 (105)376 (355)72 (65)280 (253)
Thr119.12118 (107)410 (360)71 (66)300 (259)
Cys121.26104 (109)e59 (67)254 (265)
4-hydroxy-Pro131.13366 (395)275 (293)
Ile131.18115 (118)453 (395)65 (73)335 (294)
Leu131.18124 (118)397 (395)71 (72)298 (294)
Asn132.12ded274 (296)
Asp133.11140 (120)d65 (74)285 (299)
Gln146.15ded330 (337)
Lys146.19d443 (439)d354 (337)
Glu147.13146 (133)d89 (82)316 (340)
Met149.21133 (135)397 (448)78 (83)297 (346)
His155.16169 (140)438 (465)99 (86)359 (363)
Phe165.19143 (150)485 (494)88 (93)376 (392)
Arg174.20165 (159)482 (520)111 (98)394 (418)
Tyr181.19134(164)558 (540)102 (102)457 (438)
O-Methyl-Tyr195.19622 (581)525 (479)
Trp204.23180 (186)602 (607)108 (115)508 (505)

*Adapted, with permission, from J. Magn. Reson. [11]. Copyright 2003, by Elsevier Inc.
a0.1 M solutions in H2O containing 10-5 M EDTA (ethylenediamine-N,N,N′,Ν′-tetraacetate); °C.
b Linewidths at half-height, estimated errors <±5%.
cValues into parenthesis correspond to line widths resulting from regression analysis assuming isotropic molecular motion and linear approximation.
dOverlapping resonances.
eNot measured because of degradation.
fMW of the zwitterionic form.