The synthesis and antibacterial activity of two pyoverdin-ampicillin conjugates, entering Pseudomonas aeruginosa via the pyoverdin-mediated iron uptake pathway.
Two pyoverdin-ampicillin conjugates were synthesized and their structures were confirmed by mass spectrometry and NMR spectroscopy. In contrast to ampicillin, the conjugates exhibited high antibacterial activity against Pseudomonas aeruginosa ATCC 15692 and ATCC 27853, effective only against the strain which is using the parent pyoverdin for iron uptake. This suggests that the conjugates enter the bacterial cell via the ferripyoverdin uptake pathway. Growth stimulation studies with conjugates hydrolysed at the beta-lactam ring of the ampicillin moiety supported this view.
Institute for Organic Chemistry, Köln, Germany. aco85@rsl.rrz.uni-koeln.de
O
O
Kinzel
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R
Tappe
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I
Gerus
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H
Budzikiewicz
D000667:Ampicillin / Q000138:chemical synthesis* / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D007501:Iron / Q000378:metabolism; D007502:Iron Chelating Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009842:Oligopeptides; D010860:Pigments, Biological / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000378:metabolism*; D017262:Siderophores / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism
D000900:Anti-Bacterial Agents; D007502:Iron Chelating Agents; D009842:Oligopeptides; D010860:Pigments, Biological; D017262:Siderophores; D000667:Ampicillin; C042453:pyoverdin; D007501:Iron