DNA-Binding Properties of Cosmomycin D, an Anthracycline with Two Trisaccharide Chains

Abstract

Cosmomycin D (CosD) is the major constituent fraction isolated from a culture of Streptomyces olindensis ICB20. The ability of this compound to intercalate with doublestranded DNA was studied by gel mobility shift assays and electrospray ionization mass spectrometry (ESI-MS). ESI-MS experiments showed that the complex of CosD with 16-mer double-stranded DNA was at least as stable as a complex of daunorubicin with the same DNA sequence. This is the first study showing DNA binding properties of an anthracycline Anthracyclines are an important family of natural products produced by microorganisms of the actinomycetes group. They are tetracyclic aromatic polyketides which share a 7,8,9,10-tetrahydrotetracene-5,12-quinone structure. Some members of the anthracycline group of antibiotics show interesting pharmaceutical, mostly anticancer, activities1,2). Anthracyclines that are used for cancer treatment include daunorubicin (Fig. 1A; DAU; daunomycin) and its hydroxylated derivative doxorubicin (Fig.

Screening of threading bis-intercalators binding to duplex DNA by electrospray ionization tandem mass spectrometry

“…There have been numerous ESI-MS studies that have examined the interaction between duplex DNA and well-studied, commercially available mono-intercalators such as the anthracyclines [6][7][8][9][10][11], porphyrins [12,13], ruthenium compounds [11][12][13][14][15], ethidium bromide [16][17][18], actinomycin-D [12,13], and aureolic acids [19]. Characteristics such as ligand binding stoichiometry [7,8,[11][12][13][14]16], sequence selectivity [7,11,13,14,16,19], binding mode [12,13,15] and complex stability [9,12,16] have been examined with promising results correlating the binding trends observed in the mass spectra to known solution behavior.…”

Mass spectrometric investigation of the DNA-binding properties of an anthracycline with two trisaccharide chains

“…Cosmomycin D from Streptomyces olindensis ICB20 was purified from methanol extracts of liquid cultures as previously described [18]. In some experiments, pure CosD was obtained from relatively crude culture extracts by dissolving the dried methanol extract in water, sonicating for 5 min and centrifuging in an Eppendorf microfuge (10,000 rpm, 4 °C, 15 min).…”

“…Previously we reported the purification and characterisation of an anthracycline from Streptomyces olindensis ICB20 containing a β-rhodomycinone aglycone O-linked at each of C-7 and C-10 to trisaccharide chains comprising L-rhodosamine, 2-deoxy-L-fucose and L-rhodinose [18]. This compound was identified as cosmomycin D (CosD) which was originally isolated from Streptomyces cosmosus in the mid-1980s [19,20].…”

“…Since these initial observations there had been no further investigations of the properties of this compound. Our recent work reported the first investigations of the DNA-binding properties of CosD [18]. A preliminary survey of the binding of CosD to double-stranded (ds) 16 mer DNA using electrospray ionization mass spectrometry (ESI-MS) showed that 3-4 CosD molecules bound to the DNA compared with 4-5 for Dn.…”

“…A preliminary survey of the binding of CosD to double-stranded (ds) 16 mer DNA using electrospray ionization mass spectrometry (ESI-MS) showed that 3-4 CosD molecules bound to the DNA compared with 4-5 for Dn. A gel mobility shift assay (using only one concentration of drug) showed that CosD decreased the mobility of plasmid DNA to a greater extent than Dx or Dn [18]. CosD on unwinding supercoiled plasmid DNA was investigated using agarose gels.…”