define set1 *.O?' and dna
define set2 *.OP? and dna
define set3 *.N? and dna

restrict none
select all
ribbons
color chain
pause

restrict none
select dna
wireframe
color cpk
pause

restrict none
select dna
wireframe
color cpk
select set1
cpk 100
color cpk
pause

restrict none
select dna
wireframe
color cpk
select set2
cpk 100
color cpk
pause

restrict none
select dna
wireframe
color cpk
select set3
cpk 100
color cpk
pause