Table 2.

Comparison of spatial fluctuations in 3-D structure between PTM sites and non-PTM sites. PTM annotations in UniProt/Swiss-Prot were mapped onto NMR-based 3-D structures. PTMs with one or more sites are included. The p-value for the significance of the fluctuation difference is based on two-tailed, two-sample student t-test.

PTM	UniProt keyword	# of PTM sites	Amino acid	Mean fluctuation (Å)			p-value
				PTM sites		Non-PTM sites
Phosphorylation	Phosphoserine	585	S	1.88	>	1.16	1.3E-21
Phosphorylation	Phosphothreonine	131	T	1.62	>	1.05	7.0E-5
Phosphorylation	Phosphotyrosine	164	Y	1.10	>	0.91	0.037
Phosphorylation	Phosphohistidine	4	H	2.87	>	1.01	0.224
Phosphorylation	4-aspartylphosphate	6	D	0.57	<	1.10	4.0E-5
Methylation	Omega-N-methylarginine	4	R	3.20	>	1.07	0.021
Methylation	N6-methyllysine	28	K	1.51	>	1.07	0.034
Dimethylation	Symmetric dimethylarginine	3	R	2.30	>	1.07	0.008
Dimethylation	N6,N6-dimethyllysine	13	K	2.11	>	1.07	0.011
Dimethylation	Asymmetric dimethylarginine	4	R	2.16	>	1.07	0.163
Trimethyllysine	N6,N6,N6-trimethyllysine	32	K	1.00	<	1.07	0.689
Hydroxylation	4-hydroxyproline	68	P	0.73	<	1.20	6.4E-13
Acetylation	N6-acetyllysine	395	K	1.02	<	1.07	0.348
Bromination	6′-bromotryptophan	5	W	1.50	>	0.86	0.150
Carboxylation	4-carboxyglutamate	62	E	2.13	>	1.07	7.3E-8
Palmitoylation	S-palmitoyl cysteine	9	C	2.24	>	0.87	0.004
S-Nitrosylation	S-nitrosocysteine	10	C	0.56	<	0.87	1.4E-4
Sulfation	Sulfotyrosine	6	Y	1.02	>	0.91	0.102