Abundance of Escherichia coli F1-ATPase molecules observed to rotate via single-molecule microscopy with gold nanorod probes

Journal article

The abundance of E. coli F1-ATPase molecules observed to rotate using gold nanorods attached to the γ-subunit was quantitated. Individual F1 molecules were determined to be rotating based upon time dependent fluctuations of red and green light scattered from the nanorods when viewed through a polarizing filter. The average number of F1 molecules observed to rotate in the presence of GTP, ATP, and without nucleotide was ∼50, ∼25, and ∼4% respectively. In some experiments, the fraction of molecules observed to rotate in the presence of GTP was as high as 65%. These data indicate that rotational measurements made using gold nanorods provide information of the F1-ATPase mechanism that is representative of the characteristics of the enzyme population as a whole.

Authors: York, J; Spetzler, D; Hornung, T; Ishmukhametov, R; Martin, J

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer
• Journal: Journal of Bioenergetics and Biomembranes
• Volume: 39
• Issue: 5-6
• Pages: 435-439
• Place of publication: United States
• Publication date: 2007-12-05
• DOI: 10.1007/s10863-007-9114-x
• EISSN: 1573-6881
• ISSN: 0145-479X
• Pmid: 18058004
• Language: English
• Keywords: molecular probes; nanotubes; nanotechnology; proton-translocating ATPases; microscopy; molecular probe techniques; gold; metal nanoparticles; rotation; molecular motor proteins; Escherichia coli proteins