|Ward L. Johnson
Nanometer-scale metabolically-driven fluctuations of organisms correlate with life, but the biological underpinnings of these correlations remain poorly understood at the cellular level . Over the past decade, measurements with several techniques have shown that nanomotion of microbes and sub-cellular organelles ceases at cellular death, and this has led to interest in using this effect in a variety of applications, including rapid cost-effective clinical antimicrobial susceptibility testing (AST), disease diagnostics, and research into cellular disfunction in diseases. At NIST, a highly sensitive technique was invented for sensing nanomotion of cell populations through measurements of phase noise of a resonant crystal on which cells are adhered, and correlations of noise with antibiotically-induced cell death were demonstrated with nonmotile E. coli [2,3,4]. This approach was subsequently advanced by Microbial Pulse Diagnostics LLC, with the objective of commercialization for AST . Research supporting this application and others is now transitioning back to NIST in collaboration with the Molecular Cellular and Developmental Biology Department at CU-Boulder, a team with a unique combination of expertise in microbiology, acoustics, and phase noise. We seek a postdoctoral fellow with interest in exploring biophysical mechanisms of nanomotion and/or associated responses of cells to various chemical and physical environments. Options for a postdoctoral proposal include (but are not limited to) 1) the use of cutting-edge microbial genetic and omics tools to discover genes, proteins and molecular machines required for nanomotion, 2) identification of species-specific signatures in phase-noise spectra to advance understanding of biophysical mechanisms and applications such as AST, and 3) exploration of the application of nanomotion measurements to a specific area, such as clinical or research-based AST/diagnostics, industrial quality control of probiotics, or prevention of microbially induced corrosion (MIC) of physical infrastructure.
 P. Parmar et al., “Mitochondrial nanomotion measured by optical microscopy,” Frontiers in Microbiology, March 2023, DOI:10.3389/fmicb.2023.1133773
 W. Johnson, D. C. France, T. L. Kirschling, & F. L. Walls, “Resonator and process for performing biological assay,” U.S Patent US 9,725,752 B2 . https://patentimages.storage.googleapis.com/f5/0d/31/c1a761cc10e83d/US9725752.pdf
 W. L. Johnson et al., “Sensing bacterial vibrations and early response to antibiotics with phase noise of a resonant crystal,” Scientific Reports, 7, 12138 . https://www.nature.com/articles/s41598-017-12063-6.pdf
 NIST News, “NIST’s quick test may speed antibiotic treatment and combat drug resistance,” September 2017. https://www.nist.gov/news-events/news/2017/09/nists-quick-test-may-speed-antibiotic-treatment-and-combat-drug-resistance
 F. L. Walls et al., “Rapid detection of bacterial response to antibiotics through induced phase noise of a resonant crystal,” 2021 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium. DOI: 10.1109/EFTF/IFCS52194.2021.9604273
Biosensors; Microbiology; Acoustic resonators; Phase noise; Cells; Nanomotion; Molecular machines; Antimicrobial susceptibility testing; Disease diagnostics; Microbially induced corrosion; MIC; Probiotics