load=1pp8

define protein_chains (protein and (*:M or *:Y or *:R))
define polar (oxygen or nitrogen)
define non_polar(carbon or phosphorus or sulfur)
define deoxyribose (dna and (*.C?' or *.O?'))
define phosphate ( *.OP1 or *.OP2 or *.P)
define minor ((dt and (*.N1 or *.C2 or *.O2 or *.N3)) or (da and (*.C2 or *.N3 or *.C4 or *.N9)) or (dc and (*.N1 or *.C2 or *.O2)) or (dg and (*.C2 or *.N2 or *.N3 or *.C4 or *.N9)))
define major ((dt and ( *.C4 or *.O4 or *.C5 or *.C6 or *.C7)) or (da and (*.C5 or *.C6 or *.N6 or *.N7 or *.C8)) or (dc and (*.N4 or *.C4 or *.C5 or *.C6)) or (dg and (*.C5 or *.O6 or *.C6 or *.N7 or *.C8)))

select protein_chains and polar and within (3.5, deoxyribose and polar)

select protein_chains and non_polar and within (4.5, deoxyribose and non_polar)

select protein_chains and polar and within (3.5, phosphate and polar)

select protein_chains and non_polar and within (4.5, phosphate and non_polar)

select protein_chains and polar and within (3.5, major and polar)

select protein_chains and non_polar and within (4.5, major and non_polar)

select protein_chains and polar and within (3.5, minor and polar)

select protein_chains and non_polar and within (4.5, minor and non_polar)