Reliable use of green fluorescent protein in fluorescent pseudomonads.
When fluorescent pseudomonads are cultured on standard solid media under iron limiting conditions, they produce fluorescent, pigmented iron collating agents (siderophores). Siderophores can be readily identified by strong fluorescence seen under UV/blue light. The application of the eukaryotic green fluorescent protein (GFP) as a bacterial marker in microbial ecology is increasingly being used, particularly as it is a powerful method for non-destructive monitoring in situ. As gfp expressing bacteria have to be detected under UV/blue light, the fluorescence of siderophore-producing Pseudomonas spp. masks normal levels of GFP fluorescence when colonies are viewed on standard bacterial agar. Here, we describe a simple but effective way of identifying gfp-expressing Pseudomonas fluorescens using media supplemented with 0.45 mM FeSO(4).7H(2)O. This is of relevance for the screening of insertion libraries and in the application of GFP transposons as promoter probes.
Timms-Wilson
T M
TM
Molecular Microbial Ecology, NERC, CEH-Oxford, Institute of Virology and Environmental Microbiology, Mansfield Road, Oxford, OX1 3SR, UK.
Bailey
M J
MJ
D003470:Culture Media; D004251:DNA Transposable Elements; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005290:Ferric Compounds / Q000494:pharmacology; D005453:Fluorescence; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism*; D016254:Mutagenesis, Insertional; D010957:Plasmids; D011551:Pseudomonas fluorescens / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D017262:Siderophores / Q000378:metabolism
D003470:Culture Media; D004251:DNA Transposable Elements; D005290:Ferric Compounds; D008164:Luminescent Proteins; D017262:Siderophores; D049452:Green Fluorescent Proteins; C024823:ferric sulfate