PMID- 11975993
OWN - NLM
STAT- MEDLINE
DCOM- 20020625
LR  - 20190901
IS  - 0301-4622 (Print)
IS  - 0301-4622 (Linking)
VI  - 96
IP  - 1
DP  - 2002 Apr 10
TI  - Interactions of the DNA intercalator acridine orange, with itself, with caffeine, 
      and with double stranded DNA.
PG  - 53-76
AB  - Caffeine (CAF) inhibits the intercalation of acridine orange (AO) into cellular 
      DNA. Optical absorption and fluorescence spectroscopy were employed to determine 
      the molecular interactions of AO with itself, with CAF, and with double stranded 
      herring sperm DNA (dsDNA). AO dimerization was observed at concentrations >2 
      micromol. The sharp increase in fluorescence (lambda(em)=530 nm) at 5 micromol of 
      AO was attributed to AO multimer formation. From 0.5 to 5.0 micromol, the AO 
      self-association binding constant (K(assoc)) was determined to be 38620 mol(-1), 
      however, the presence of 150 mmol NaCl increased K(assoc) to 118000 mol(-1) 
      attributed to the charge neutralization. The K(assoc) for AO with CAF was 
      confirmed to be 256 mol(-1). K(assoc) for the binding of AO with 20 micromol DNA 
      ranged from, 32000 mol(-1) at 2 micromol AO, to approximately 3700 mol(-1) at 10 
      micromol AO, in the absence of NaCl. This AO concentration dependency of K(assoc) 
      value with DNA was attributed to AO intercalation into dsDNA at high dsDNA/AO 
      ratios, and electrostatic binding of AO to dsDNA at low AO ratios. The findings 
      provide information used to explain fluorescence intensity values at lambda(em) 
      at 530 nm from studies that combine AO, caffeine, and dsDNA.
FAU - Lyles, Mark B
AU  - Lyles MB
AD  - Department of Cellular and Structural Biology, University of Texas Health Science 
      Center at San Antonio, 7703 Floyd Curl Drive, 78229-3900, USA.
FAU - Cameron, Ivan L
AU  - Cameron IL
LA  - eng
GR  - DE00152/DE/NIDCR NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - Netherlands
TA  - Biophys Chem
JT  - Biophysical chemistry
JID - 0403171
RN  - 0 (Intercalating Agents)
RN  - 0 (Mutagens)
RN  - 3G6A5W338E (Caffeine)
RN  - 451W47IQ8X (Sodium Chloride)
RN  - 9007-49-2 (DNA)
RN  - F30N4O6XVV (Acridine Orange)
SB  - IM
MH  - Acridine Orange/*chemistry
MH  - Caffeine/*chemistry
MH  - DNA/*chemistry
MH  - Intercalating Agents/*chemistry
MH  - Kinetics
MH  - Mutagens/*chemistry
MH  - Sodium Chloride/chemistry
MH  - Spectrometry, Fluorescence
MH  - Spectrophotometry, Ultraviolet
EDAT- 2002/04/27 10:00
MHDA- 2002/06/26 10:01
CRDT- 2002/04/27 10:00
PHST- 2002/04/27 10:00 [pubmed]
PHST- 2002/06/26 10:01 [medline]
PHST- 2002/04/27 10:00 [entrez]
AID - S0301462202000364 [pii]
AID - 10.1016/s0301-4622(02)00036-4 [doi]
PST - ppublish
SO  - Biophys Chem. 2002 Apr 10;96(1):53-76. doi: 10.1016/s0301-4622(02)00036-4.