Microcalorimetric and spectroscopic investigation of the antibacterial properties of cationic ytterbium(III)-porphyrin complexes lacking charged peripheral groups.
The antibacterial activities towards Escherichia coli of two cationic Yb(III)-monoporphyrin complexes, [Yb(III)(TMP)(H2O)3]Cl (1) and [Yb(III)(TTP)(H2O)3]Cl (2), were investigated at the cellular and sub-cellular levels. The biological effects of the complexes on the growth of E. coli were evaluated by microcalorimetry and by analysis of the resulting metabolic thermogenic curves, from which IC50 values and metabolic parameters such as growth rate and generation time were derived. At the subcellular level, DNA-binding experiments were performed by means of UV/VIS- and fluorescence-titration experiments, as well as by near-infrared (NIR) emission, which revealed that 1 and 2 strongly bind to herring-sperm DNA (HS-DNA), though by different binding modes.
Hou
An-Xin
AX
Department of Chemistry, Wuhan University, Wuhan 430072, PR China. houanxin@yahoo.com
Xue
Zhi
Z
Liu
Yi
Y
Qu
Song-Sheng
SS
Wong
Wai-Kwok
WK
D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D002151:Calorimetry; D002412:Cations / Q000737:chemistry; D004926:Escherichia coli / Q000187:drug effects; D015394:Molecular Structure; D011166:Porphyrins / Q000737:chemistry* / Q000494:pharmacology*; D013696:Temperature; D013816:Thermodynamics; D017186:Titrimetry; D015018:Ytterbium / Q000737:chemistry*
D000900:Anti-Bacterial Agents; D002412:Cations; D011166:Porphyrins; D015018:Ytterbium