Study of membrane proteins at the molecular level is one of the major challenges for today's biologists. ATP-binding cassette (ABC) transporters are one of the largest and most diverse superfamily of membrane proteins found in all living organisms ranging from bacteria to human. All ABC transporters share a common structure organization, suggesting a similar mechanism of energy coupling. ABC transporters are medically relevant. For instance, they are responsible for severe sicknesses and multidrug resistance in bacteria and cancer chemotherapy. Despite extensive studies, the molecular mechanism of ABC transporters remains elusive and many questions remain unanswered. In this proposal, we aim to develop single nanoparticle optical assays for real-time characterizing the functioning mechanism of BmrA, a multidrug bacterial transporter belonging to the ABC transporter superfamily. The specific research aims are described below:
Aim 1 : We will develop the optimum nanoparticle probes for tracing the transport mechanisms and kinetics of BrmA (WT) and their mutants in real-time at the single transporter resolution with high temporal and spatial information, aiming to determine individual steps of the catalytic cycle directly responsible for substrate translocation. Combining with high-resolution transmission electron microscopy (TEM) imaging, we aim to depict the transport pathways and verify proposed models.
Aim 2 :
We aim to use the optimum nanoparticle probes developed in Aim 1 to trace the real-time transport mechanism and kinetics of drugs and genes via the ABC transporter. In addition, we will determine the nanoparticles that can escape the extrusion mechanisms of ABC transporter, and use them as carriers to deliver genes and drugs into living cells, aiming to explore the effective delivery means for better therapy.
Aim 3 : We will study the biocompatibility of nanoparticles at the cellular and genomic level, aiming to design biocompatible nanoparticles for molecular study of the ABC transports in living cells in real-time. The outcomes include: new nanoparticle assays for real-time measurement of membrane transport pathways and mechanisms of membrane transporters;better understanding of fundamental mechanism of ABC membrane transport;and effective means for the delivery of genes and drugs into living cells.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Research Project (R01)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-BCMB-A (50))
Program Officer
Lewis, Catherine D
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Old Dominion University
Schools of Arts and Sciences
United States
Zip Code
Browning, Lauren M; Lee, Kerry J; Cherukuri, Pavan K et al. (2018) Single gold nanoparticle plasmonic spectroscopy for study of chemical-dependent efflux function of single ABC transporters of single live Bacillus subtilis cells. Analyst 143:1599-1608
Ding, Feng; Songkiatisak, Preeyaporn; Cherukuri, Pavan Kumar et al. (2018) Size-Dependent Inhibitory Effects of Antibiotic Drug Nanocarriers against Pseudomonas aeruginosa. ACS Omega 3:1231-1243
Browning, Lauren M; Lee, Kerry J; Nallathamby, Prakash D et al. (2016) Single Nanoparticle Plasmonic Spectroscopy for Study of Charge-Dependent Efflux Function of Multidrug ABC Transporters of Single Live Bacillus subtilis Cells. J Phys Chem C Nanomater Interfaces 120:21007-21016
Browning, Lauren M; Lee, Kerry J; Cherukuri, Pavan K et al. (2016) Single Nanoparticle Plasmonic Spectroscopy for Study of the Efflux Function of Multidrug ABC Membrane Transporters of Single Live Cells. RSC Adv 6:36794-36802
Lee, Kerry J; Huang, Tao; Nallathamby, Prakash D et al. (2015) Wavelength dependent specific plasmon resonance coupling of single silver nanoparticles with EGFP. Nanoscale 7:17623-30
Ding, Feng; Lee, Kerry J; Vahedi-Faridi, Ardeschir et al. (2014) Design and study of the efflux function of the EGFP fused MexAB-OprM membrane transporter in Pseudomonas aeruginosa using fluorescence spectroscopy. Analyst 139:3088-96
Xu, Xiao-Hong Nancy; Wen, Zhaoyang; Brownlow, William J (2013) Ultrasensitive Analysis of Binding Affinity of HIV Receptor and Neutralizing Antibody Using Solution-Phase Electrochemiluminescence Assay. J Electroanal Chem (Lausanne) 688:53-60
Browning, Lauren M; Huang, Tao; Xu, Xiao-Hong Nancy (2013) Real-time in vivo imaging of size-dependent transport and toxicity of gold nanoparticles in zebrafish embryos using single nanoparticle plasmonic spectroscopy. Interface Focus 3:20120098
Lee, Kerry J; Browning, Lauren M; Nallathamby, Prakash D et al. (2013) Silver nanoparticles induce developmental stage-specific embryonic phenotypes in zebrafish. Nanoscale 5:11625-36
Browning, Lauren M; Lee, Kerry J; Nallathamby, Prakash D et al. (2013) Silver nanoparticles incite size- and dose-dependent developmental phenotypes and nanotoxicity in zebrafish embryos. Chem Res Toxicol 26:1503-13

Showing the most recent 10 out of 28 publications