Table 3

Spectrum of mutations appearing in α-helix, β-strand, turn and bend structures, expected values are calculated from mutated and mutant amino acid composition in the studied proteinsa

Amino acid

Original residues

Expected residues

χ2

P value

Mutant residues

Expected residues

χ2

P value


A

148

136

1.07

3.00E-01

58

67

1.15

2.84E-01

C

54

64

1.43

2.32E-01

117

107

0.94

3.32E-01

D

81

79

0.06

8.06E-01

112

125

1.28

2.57E-01

E

96

91

0.29

5.91E-01

71

68

0.18

6.75E-01

F

53

53

0.00

9.91E-01

77

72

0.29

5.87E-01

G

220

198

2.48

1.15E-01

95

85

1.12

2.91E-01

H

63

70

0.69

4.05E-01

91

87

0.20

6.57E-01

I

83

80

0.14

7.05E-01

55

64

1.36

2.44E-01

K

43

45

0.09

7.61E-01

92

88

0.21

6.43E-01

L

188

186

0.03

8.70E-01

96

91

0.29

5.91E-01

M

65

63

0.08

7.74E-01

48

78

11.54***

6.79E-04

N

60

72

2.12

1.46E-01

61

60

0.04

8.47E-01

P

68

76

0.76

3.82E-01

170

156

1.25

2.63E-01

Q

45

50

0.47

4.91E-01

89

92

0.13

7.17E-01

R

299

280

1.31

2.53E-01

196

179

1.71

1.91E-01

S

78

101

5.05*

2.46E-02

144

140

0.12

7.31E-01

T

62

68

0.46

4.99E-01

119

109

0.85

3.57E-01

V

122

118

0.12

7.28E-01

138

149

0.78

3.77E-01

W

44

44

0.00

9.72E-01

56

62

0.57

4.51E-01

Y

67

68

0.00

9.46E-01

54

61

0.83

3.62E-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.

Khan and Vihinen BMC Structural Biology 2007 7:56   doi:10.1186/1472-6807-7-56

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