title: Isolation of two Pseudomonas strains producing pseudomonic acid A.
abstract: Two novel Pseudomonas strains were isolated from groundwater sediment samples. The strains showed resistance against the antibiotics tetracycline, cephalothin, nisin, vancomycin, nalidixic acid, erythromycin, lincomycin, and penicillin and grew at temperatures between 15 and 37 degrees C and pH values from 4 to 10 with a maximum at pH 7 to 10. The 16S ribosomal RNA gene sequences and the substrate spectrum of the isolates revealed that the two strains belonged to the Pseudomonas fluorescens group. The supernatants of both strains had an antibiotic effect against Gram-positive bacteria and one Gram-negative strain. The effective substance was produced under standard cultivation conditions without special inducer molecules or special medium composition. The antibiotically active compound was identified as pseudomonic acid A by off-line high performance liquid chromatography (HPLC) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The measurement on ultra performance liquid chromatography (UPLC, UV-vis detection) confirmed the determination of pseudomonic acid A which was produced by both strains at 1.7-3.5mg/l. Our findings indicate that the ability to produce the antibiotic pseudomonic acid A (Mupirocin) is more spread among the pseudomonads then anticipated from the only producer known so far.
authors.affiliation: Institute of Groundwater Ecology, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Fritz
authors.forename: Agnes
authors.initials: A
authors.lastname: Fekete
authors.forename: Jutta
authors.initials: J
authors.lastname: Lintelmann
authors.forename: Philipe
authors.initials: P
authors.lastname: Schmitt-Kopplin
authors.forename: Rainer U
authors.initials: RU
authors.lastname: Meckenstock
mesh_terms: D002851:Chromatography, High Pressure Liquid; D024881:Drug Resistance, Bacterial; D005583:Fourier Analysis; D005618:Fresh Water / Q000382:microbiology; D019015:Geologic Sediments / Q000382:microbiology; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D013058:Mass Spectrometry / Q000379:methods; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D016712:Mupirocin / Q000096:biosynthesis* / Q000737:chemistry / Q000494:pharmacology; D011549:Pseudomonas / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D017422:Sequence Analysis, DNA
chemical_list: D016712:Mupirocin