Hello 정준-- First, the Fiber diffraction facility is only available via the old XPLOR interface so you are currently stuck with its limitations, and my lack of knowledge.
> > 1 Helix arrangement and NCS settings > My system contains a strongly crystalline 3/1 helix (three residues per > pitch), and unit-cell indexing has been determined as an orthorhombic cell > with parameters 23 Å, 10 Å, 8.26 Å, 90°, 90°, 90°. Within each cell, two > antiparallel helices are present. In the ncs strict protocol, only > translations along Z appear to be enforced. However, I would like to include > both helices in a single PDB file and simply replicate (extend) them along > the Z axis—without applying any additional rotations—since each residue is > already rotated by 120° in the input file. Which Xplor-NIH INP parameter(s) > should I use to achieve this “pure Z-axis expansion” of all helices in the > unit cell? Alternatively, is there a way within Xplor-NIH to translate the > helices along the X and Y axes and enforce their antiparallel symmetry prior > to performing fiber diffraction refinement? If your PDB contains an entire unit cell's worth of atoms, then NCS strict statements should not be necessary. > > 2 Order of intensity data in the layer-line file > In a line such as > > LAYER LINE 0 HIGHEST R 477 LOWEST R 1 > > should the corresponding intensity values be listed in order from > highest R → lowest R, or from lowest R → highest R? lowest to highest (from reading the source). You might glean further insight by checking the test/fiber.inp and test/fiber2.inp files in the Xplor-NIH distribution. And do not hesitate to ask if you have further questions. Charles ######################################################################## To unsubscribe from the XPLOR-NIH list, click the following link: http://list.nih.gov/cgi-bin/wa.exe?SUBED1=XPLOR-NIH&A=1
