TY - JOUR
T1 - Adaptor protein mediates dynamic pump assembly for bacterial metal efflux
AU - Santiago, Ace George
AU - Chen, Tai Yen
AU - Genova, Lauren A.
AU - Jung, Won
AU - Thompson, Alayna M.George
AU - Mcevoy, Megan M.
AU - Chen, Peng
N1 - Funding Information:
We acknowledge the Army Research Office (Grant 66998LS) and the NIH (Grants AI117295, GM109993, GM106420, GM079192, and 5T32GM008500) for funding, Cornell University Biotechnology Resource Center (New York State Stem Cell Science Program Grant CO29155 and NIH Grant S10OD018516) for access to the Zeiss LSM880 confocal microscope, and Y. Aye for access to immunoblot imaging instrument.
PY - 2017/6/27
Y1 - 2017/6/27
N2 - Multicomponent efflux complexes constitute a primary mechanism for Gram-negative bacteria to expel toxic molecules for survival. As these complexes traverse the periplasm and link inner and outer membranes, it remains unclear how they operate efficiently without compromising periplasmic plasticity. Combining single-molecule superresolution imaging and genetic engineering, we study in living Escherichia coli cells the tripartite efflux complex CusCBA of the resistance-nodulation-division family that is essential for bacterial resistance to drugs and toxic metals. We find that CusCBA complexes are dynamic structures and shift toward the assembled form in response to metal stress. Unexpectedly, the periplasmic adaptor protein CusB is a key metal-sensing element that drives the assembly of the efflux complex ahead of the transcription activation of the cus operon for defending against metals. This adaptor protein-mediated dynamic pump assembly allows the bacterial cell for efficient efflux upon cellular demand while still maintaining periplasmic plasticity; this could be broadly relevant to other multicomponent efflux systems.
AB - Multicomponent efflux complexes constitute a primary mechanism for Gram-negative bacteria to expel toxic molecules for survival. As these complexes traverse the periplasm and link inner and outer membranes, it remains unclear how they operate efficiently without compromising periplasmic plasticity. Combining single-molecule superresolution imaging and genetic engineering, we study in living Escherichia coli cells the tripartite efflux complex CusCBA of the resistance-nodulation-division family that is essential for bacterial resistance to drugs and toxic metals. We find that CusCBA complexes are dynamic structures and shift toward the assembled form in response to metal stress. Unexpectedly, the periplasmic adaptor protein CusB is a key metal-sensing element that drives the assembly of the efflux complex ahead of the transcription activation of the cus operon for defending against metals. This adaptor protein-mediated dynamic pump assembly allows the bacterial cell for efficient efflux upon cellular demand while still maintaining periplasmic plasticity; this could be broadly relevant to other multicomponent efflux systems.
KW - Metal sensing
KW - Multicomponent efflux complex
KW - Periplasmic adaptor protein
KW - Single-molecule tracking
KW - Substrate-responsive dynamic assembly
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U2 - 10.1073/pnas.1704729114
DO - 10.1073/pnas.1704729114
M3 - Article
C2 - 28607072
AN - SCOPUS:85021398652
SN - 0027-8424
VL - 114
SP - 6694
EP - 6699
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 26
ER -