Phase problem: Difference between revisions

(2 intermediate revisions by the same user not shown)

Line 6:

A recent introduction into the principles of phase calculation with the help of experiments (SIR/MIR/SIRAS/MIRAS/SAD/MAD) can be e.g. found in Taylor, G. (2003) The phase problem. Acta Cryst D59, 1881-1890 [http://journals.iucr.org/d/issues/2003/11/00/ba5050/index.html]. Requirement for applicability of [[experimental phasing]] is [[isomorphism]] between heavy-atom derivative and native (i.e. the macromolecule itself, and the crystal's cell should be unchanged), specific binding of heavy atom, and enough heavy-atom incorporation into the crystal.

A vey good recent paper is A. J. McCoy and R. J. Read (2010) Experimental phasing: best practice and pitfalls. Acta Cryst D66, 458-469 (open access at [http://dx.doi.org/10.1107/S0907444910006335])

== [[molecular replacement|Molecular Replacement]] (MR) ==

Line 14:

Line 15:

== [[direct methods|Direct Methods]] ==

The solution of the phase problem with the help of [[direct methods|Direct Methods]] was awarded with the Nobel Prize in 1985 ([http://www.iucr.org/people/nobel-prize]). In the context of macromolecular crystallography, this approach is used in substructure determination, and at very high resolution (beyond 1.2A).

The solution of the phase problem with the help of [[direct methods|Direct Methods]] was awarded with the Nobel Prize in 1985 ([http://www.iucr.org/people/nobel-prize]). For an example, see [[Solve a small-molecule structure]].

In the context of macromolecular crystallography, this approach is used in substructure determination, and at very high resolution (beyond 1.2A). See also [[SHELX C/D/E]].

@@ Line 6: / Line 6: @@
 A recent introduction into the principles of phase calculation with the help of experiments (SIR/MIR/SIRAS/MIRAS/SAD/MAD) can be e.g. found in Taylor, G. (2003) The phase problem. Acta Cryst D59, 1881-1890 [http://journals.iucr.org/d/issues/2003/11/00/ba5050/index.html]. Requirement for applicability of [[experimental phasing]] is [[isomorphism]] between heavy-atom derivative and native (i.e. the macromolecule itself, and the crystal's cell should be unchanged), specific binding of heavy atom, and enough heavy-atom incorporation into the crystal.
+A vey good recent paper is A. J. McCoy and R. J. Read (2010) Experimental phasing: best practice and pitfalls. Acta Cryst D66, 458-469 (open access at [http://dx.doi.org/10.1107/S0907444910006335])
 == [[molecular replacement|Molecular Replacement]] (MR) ==
@@ Line 14: / Line 15: @@
 == [[direct methods|Direct Methods]] ==
-The solution of the phase problem with the help of [[direct methods|Direct Methods]] was awarded with the Nobel Prize in 1985 ([http://www.iucr.org/people/nobel-prize]). In the context of macromolecular crystallography, this approach is used in substructure determination, and at very high resolution (beyond 1.2A).
+The solution of the phase problem with the help of [[direct methods|Direct Methods]] was awarded with the Nobel Prize in 1985 ([http://www.iucr.org/people/nobel-prize]). For an example, see [[Solve a small-molecule structure]].
+In the context of macromolecular crystallography, this approach is used in substructure determination, and at very high resolution (beyond 1.2A). See also [[SHELX C/D/E]].