Spectrum of disease-causing mutations in protein secondary structures

BMC Structural Biology

Table 4 Spectrum of mutations appearing in α-helix, β-strand, turn and bend structures. Expected values are calculated from amino acid composition in secondary structural elements^a

Amino acid	Original residues	Expected residues	χ²	P value	Mutant residues	Expected residues	χ²	P value
A	148	139	0,53	4.66E-01	58	119	31.05***	2.51E-08
C	54	32	15,50***	6.82E-05	117	69	32.93***	9.58E-09
D	81	96	2,34	1.26E-01	112	79	13.64***	2.21E-04
E	96	147	17,60***	2.71E-05	71	69	0.04	8.33E-01
F	53	87	13,51***	2.36E-04	77	79	0.06	8.10E-01
G	220	136	52,47***	4.48E-13	95	114	3.10	7.85E-02
H	63	48	5,06*	2.47E-02	91	79	1.78	1.83E-01
I	83	110	6,51**	1.07E-02	55	104	23.00***	1.62E-06
K	43	113	43,42***	4.37E-11	92	69	7.47**	6.26E-03
L	188	205	1,34	2.46E-01	96	163	27.69***	1.42E-07
M	65	49	5,02*	2.51E-02	48	45	0.27	6.02E-01
N	60	69	1,10	2.93E-01	61	79	4.16*	4.14E-02
P	68	67	0,02	8.98E-01	170	119	22.16***	2.51E-06
Q	45	82	16,87***	3.98E-05	89	69	5.63*	1.76E-02
R	299	119	272,51***	3.43E-61	196	168	4.60*	3.19E-02
S	78	104	6,60**	1.01E-02	144	183	8.32**	3.92E-03
T	62	92	10,03**	1.53E-03	119	119	0.00	9.79E-01
V	122	144	3,33	7.01E-02	138	119	3.13	7.67E-02
W	44	30	6,27**	1.23E-02	56	35	13.20***	2.81E-04
Y	67	70	0,15	6.95E-01	54	59	0.48	4.87E-01
Sum	1939	1939			1939	1939

^aχ²-numbers in italics indicate underrepresentation and numbers in bold overrepresentation compared to random distribution based on amino acid frequencies. The results of the χ² are shown with significance level: * P < 0.05; ** P < 0.01; *** P < 0.001.

ISSN: 1472-6807