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How do I select residues in a particular chain?

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How do I select residues in a particular chain?

The method for selecting a range of residues in a particular chain has improved in RasMol version 2.6. It can now be done using the syntax "select 1-25:a" to select residues 1 to 25 in chain A. Similarly "select 25:a" and "select :a" will select just residue 25 in chain A and all of chain A respectively.

In RasMol versions prior to v2.6, you'd have to type an atom expression of the form "select 1-25 and **a" where the final term is a primitive expression. This primitive expression is a wildcarded form of the form "cys37a" where the residue name and number are replaced by the wildcard "*".

Note that care has to be made to ensure that RasMol can determine which field is being specified. For example, although "select *a" will select all resiues in chain A, if the chain identifier was a number, "select **1" would have to be used, as "select *1" denotes residue 1. To avoid any ambiguity, an optional colon character is now used to prefix the chain identifier, allowing expressions such as "cys:a", "cys35:1", "*:1" and even just ":1".

See also the RasMol Manual.

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