High-sensitivity bacterial detection using biotin-tagged phage and quantum-dot nanocomplexes.
With current concerns of antibiotic-resistant bacteria and biodefense, it has become important to rapidly identify infectious bacteria. Traditional technologies involving isolation and amplification of the pathogenic bacteria are time-consuming. We report a rapid and simple method that combines in vivo biotinylation of engineered host-specific bacteriophage and conjugation of the phage to streptavidin-coated quantum dots. The method provides specific detection of as few as 10 bacterial cells per milliliter in experimental samples, with an approximately 100-fold amplification of the signal over background in 1 h. We believe that the method can be applied to any bacteria susceptible to specific phages and would be particularly useful for detection of bacterial strains that are slow growing, e.g., Mycobacterium, or are highly infectious, e.g., Bacillus anthracis. The potential for simultaneous detection of different bacterial species in a single sample and applications in the study of phage biology are discussed.
Edgar
Rotem
R
National Cancer Institute, Bethesda, MD 20892-4264, USA.
McKinstry
Michael
M
Hwang
Jeeseong
J
Oppenheim
Amos B
AB
Fekete
Richard A
RA
Giulian
Gary
G
Merril
Carl
C
Nagashima
Kunio
K
Adhya
Sankar
S
D001435:Bacteriophages / Q000737:chemistry*; D001710:Biotin / Q000032:analysis* / Q000737:chemistry; D005434:Flow Cytometry; D006090:Gram-Negative Bacteria / Q000302:isolation & purification*; D006094:Gram-Positive Bacteria / Q000302:isolation & purification*; D008856:Microscopy, Fluorescence; D036103:Nanotechnology / Q000379:methods*; D045663:Quantum Dots; D012680:Sensitivity and Specificity; D013997:Time Factors
D001710:Biotin