Rapid screening method for the detection of antimicrobial substances.
Bioluminescence is phenomenon where living organisms produce light and this production is directly dependent on metabolic activity of the organism. Genes encoding enzymes, luciferases, responsible for light production can be cloned into indicator strains, thus allowing sensitive detection of antimicrobial activity. This study utilized bacterial luciferase genes cloned into Staphylococcus aureus, Escherichia coli and Salmonella enterica serovar Typhimurium indicator strains and showed that the detection of antimicrobial activity can be obtained already in 2 h without laborious plate counting and overnight incubation. Indicator strains used in the study harboured luxAB genes responsible of producing light as well as luxCDE genes for synthesis of long-chain fatty aldehyde as substrate for light production. As a consequence, no exogenous aldehyde addition was needed allowing stable light production. Furthermore, the method was used for the detection of antimicrobial activity from lactic acid bacteria after the effect of organic acids was eliminated.
Department of Biochemistry and Food Chemistry, University of Turku, Itäinen Pitkäkatu 4A, 20014 Turku, Finland. satu.vesterlund@utu.fi
Satu
S
Vesterlund
Johanna
J
Paltta
Andrea
A
Lauková
Matti
M
Karp
Arthur C
AC
Ouwehand
D000900:Anti-Bacterial Agents / Q000032:analysis*; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D007777:Lactobacillaceae / Q000378:metabolism; D008156:Luciferases / Q000032:analysis* / Q000235:genetics / Q000378:metabolism; D008163:Luminescent Measurements; D009561:Nisin / Q000378:metabolism; D012486:Salmonella typhimurium / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D013211:Staphylococcus aureus / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D013752:Tetracycline / Q000378:metabolism; D014169:Transformation, Bacterial / Q000235:genetics
D000900:Anti-Bacterial Agents; D009561:Nisin; D008156:Luciferases; D013752:Tetracycline