background white
define set1 dna and *.O4*
define set2 dna and *.O?P
define set3 dna and *.N?

restrict none
select not dna
ribbon
select backbone and dna
backbone
color orange
select not *.P and dna
color cpk
wireframe
echo The whole structure
pause

restrict dna
zoom 200
center
echo Only DNA
pause

select set1
spacefill 200
color red
echo DNA: desoxyribose oxygenes
pause

spacefill off
color cpk
select set2
spacefill 200
color red
echo DNA: phoshpate oxygenes
pause

spacefill off
color cpk
select set3
spacefill 200
color blue
echo DNA: nitrogenes
pause