Skip to main content

Table 4 Most common secondary structures involving different types of π-turns and their immediate neighborsa

From: pi-Turns: types, systematics and the context of their occurrence in protein structures

 

Secondary structures at positionsb

  

Turn

i-1

i

i+1

i+2

i+3

i+4

i+5

i+6

Number

Percentagec

Ï€-HB

AAAa

E

E

T

T

T

T

E

E

245

70

PgAA

C

C

B

T

T

T

B

C

8

15

pAAa

E

E

T

T

T

T

E

E

10

42

Ï€-NHB

AEAA

E

E

S

S

T

T

S

C

14

4

 

H

H

T

S

T

T

C

C

13

4

 

E

E

S

S

T

T

C

C

12

4

 

C

T

T

S

T

T

C

C

12

4

EAAa

E

E

C

T

T

S

C

E

86

31

 

E

E

C

T

T

C

C

E

68

24

 

C

B

C

T

T

S

C

B

16

6

EAAA

C

C

C

T

T

T

H

H

13

6

EAAE

E

E

C

S

S

C

E

E

73

41

AAaA

E

C

T

T

S

S

E

E

47

28

 

E

C

T

T

S

S

C

E

13

8

AEEa

H

H

T

S

T

T

C

C

10

6

 

C

T

T

S

T

T

C

C

10

6

  1. aThe combination of secondary structures with >10 occurrence are shown. There is no occurrence of isolated AAAA and AAAa types of π-HB turns immediately after the α-helix.
  2. bAccording to DSSP notation E: β-strand, T: hydrogen-bonded turn, B: isolated β-bridge, S: bend and we represent non-regular structure by C.
  3. cBased on the number observed with the given combination of secondary structures (given in the previous column) relative the total number in the class.