Novel Multimodal Chemical Nano-Imaging Approach to Visualize and Identify Small Biomolecules Exchanged in Microbial Communities
EMSL Project ID
60588
Abstract
The ability to chemically visualize biological systems and processes on the nanometer length scale under relevant physiological conditions is an unmet need that if realized would revolutionize our understanding of intercellular communication. This need, which is also identified in the 2017 Biological and Environmental Research Advisory Committee (BERAC) Grand Challenge Report, stems from the fact that existing genomic and biochemical methods cannot directly image and identify small biomolecules and are therefore limited in the information they can provide, particularly for complex samples. To meet this need, we will develop methods and technologies for real-space in situ topographic and chemical nano-imaging of small biomolecules involved in microbial communication with high spatial resolution. Our BioImaginG Technology Using Nano-optical Approaches (BIGTUNA) instrument will combine several chemically selective hyperspectral optical microscopic methods with nano-optics tools to enable multimodal chemical imaging in situ with down to 1–2 nanometer spatial resolution. Specifically, in a single setup, we will combine spatio-spectrally resolved optical absorption/reflectance/scattering, Raman/fluorescence, and coherent Raman/two-photon fluorescence/second harmonic generation spectroscopy with atomic force microscopy (AFM). Nanoscale resolution in optical spectroscopy will be attained through the unique properties of metallic AFM probes that can localize and enhance incident and scattered optical fields. Biomolecules in the immediate vicinity of the apex of the AFM probe will be precisely located and identified through their characteristic optical spectra that report on their vibrational and electronic properties. This will enable the chemical identification of biomolecules that govern intercellular communication over the length scale of a few nanometers. Our instrument will provide significant advantages over currently employed approaches for metabolic mapping, simultaneously achieving:
(i) ultrahigh spatial resolution in chemical imaging, down to 1–2 nm under relevant physiological conditions, which is required for real-space visualization of metabolites in action
(ii) ultrahigh detection sensitivity down to a single/a few molecules by taking advantage of localized and enhanced optical fields in the vicinity of a metallic AFM probe
(iii) fast acquisition speeds facilitated by large optical signal enhancement using metallic probes, as well as time series analysis and machine learning
(iv) ease of switching between the various linear and nonlinear chemical nano-spectroscopy and nano-imaging modalities, which will all be implemented in a single optical platform.
We will test our platform using a model microbial system that is involved in controlling carbon cycling in the environment. Specifically, we will record detailed multimodal chemical nano-images of extracellular matrices to reveal the chemical identities of small biomolecules and heme proteins involved in communication between syntrophic, anaerobic, methane-oxidizing archaea and sulfate-reducing bacteria in a natural microbial community. Our platform will significantly advance the existing fundamental understanding of metabolic processes and interactions that take place not only in this syntrophic community, but in a larger set of Biological and Environmental Research (BER) program-relevant systems as well. Namely, our multimodal chemical nano-imager will ultimately allow the detection, visualization, and identification of biomolecules encountered throughout intercellular communication, (biologically assisted) decomposition of natural/synthetic polymers, and plant–microbe interactions, all of which are active areas of research in BER’s portfolio.
Project Details
Start Date
2022-10-01
End Date
N/A
Status
Active
Released Data Link
Team
Principal Investigator
Team Members