Site specificity of psoralen-DNA interstrand cross-linking determined by nuclease Bal31 digestion

Journal Article · Tue Oct 21 00:00:00 EDT 1986 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00369a039· OSTI ID:6619398

Zhen, W; Buchardt, O; Nielsen, H; Nielsen, P E

A novel method for determination of psoralen photo-cross-linking sites in double-stranded DNA is described, which is based on a pronounced inhibition of Bal31 exonuclease activity by psoralen-DNA interstrand cross-links. The results using a 51 base pair fragment of plasmid pUC19 and a 346 base pair fragment of pBR322 show that 5'-TA sequences are preferred cross-linking sites compared to 3'-TA sequences. They also indicate that sequences flanking the 5'-TA site influence the cross-linking efficiency at the site. The DNA photo-cross-linking by 4,5',8-trimethylpsoralen and 8-methoxypsoralen was analyzed, and these two psoralens showed identical site specificity. The 5'-TA preference is rationalized on the basis of the local DNA structure in terms of ..pi..-..pi.. electronic interaction between the thymines and the intercalated psoralens, as well as on the base tilt angles of the DNA.

• Research Organization: Univ. of Copenhagen, Denmark
• OSTI ID: 6619398
• Journal Information: Biochemistry; (United States), Vol. 25:21
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
DNA
CROSS-LINKING
NUCLEASES
BIOCHEMISTRY
PSORALEN
ATP
ENZYME ACTIVITY
ESCHERICHIA COLI
MOLECULAR STRUCTURE
PHOSPHORUS 32
PLASMIDS
ANTICOAGULANTS
BACTERIA
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHEMISTRY
COUMARINS
DAYS LIVING RADIOISOTOPES
DRUGS
ENZYMES
ESTERASES
HEMATOLOGIC AGENTS
HETEROCYCLIC COMPOUNDS
HYDROLASES
ISOTOPES
LIGHT NUCLEI
MICROORGANISMS
NUCLEI
NUCLEIC ACIDS
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PHOSPHODIESTERASES
PHOSPHORUS ISOTOPES
POLYMERIZATION
RADIOISOTOPES
550201* - Biochemistry- Tracer Techniques