other determinations ( supercoil relaxation , t7 gene 3 product sensitivity , bromoacetaldehyde reactivity , anomalous gel mobility , the influence of negative superhelical density on nuclease sensitivity ) led to the conclusion that the b-helix deformation was not due to a previously recognized dna conformation ( left-handed z-dna , cruciform , bent dna ) , but may be accounted for by the homopurine x homopyrimidine nature of this region .
C0043442
left-handed
C0012854
dna