reset
load=1I3J
define set1 (*.O3' or *.O4' or *.O5')
define set2 (*.OP1 or *.OP2)
define set3 (*.N? and dna)
set echo top right
zoom 70
select dna
cpk off
wireframe off
cartoon
select protein
cartoon
color translucent
echo "Protein & DNA"
pause

restrict dna
center selected
echo "DNA"
pause
select set1
cpk 140
echo "oxygen atoms of 2'-deoxyribose"
pause

select set1
cpk off
select set2
cpk 140
echo "oxygen atoms in the phosphoric acid residue"
pause

select set2
cpk off
select set3
cpk 140
echo "nitrogen atoms in nitrogenous bases"
pause