[modeller_usage] Question about chi dihedral angle cubic spline restraint

["Lee, Jinhyuk" <>]

Dear all,

I have a question about chi dihedral angle in rsr (restraint) file.

The following is one of chi1 dihedral angles.

R   10  22   3  14   4  28   0     1     2     3     4       1.0000   -3.1416    3.1584    0.3000    0.1072   -1.8388    0.3519   0.5736    1.8270    4.1095    4.6770    1.6637    0.1167    0.0925    1.5911    4.6125    7.2224    6.4874    3.6210    1.5701    0.8375    1.4232    3.3272    6.1649    5.4708    2.8728    1.0891    0.3370

I think that the 14th and 15th columns (-3.1416  and  3.1584) represent the low and high points, respectively.

The chi angle should be periodic from -pi to pi radians, but two values do not agree with pi and -pi.

When I generated the spline function using these data and the values at pi and -pi seems to be disagreement.

Is there any reason of using -3.1416 and 3.1584 not pi and -pi? 

Thanks,

--
Jinhyuk