# A Biosinpired Genetically-Expressible Dual-Modality Peptide-Based Probe for Super-Resolution Correlative Light and Electron Microscopy > **NIH NIH R41** · PHOTON BIOSCIENCES, LLC · 2024 · $299,812 ## Abstract 1 Abstract 2 The overall goal of this project is to rationally engineer a new genetically expressible lanthanide-based 3 photostable phosphorescent probe with time-integrated single molecule brightness and high electron density 4 for Super Resolution Correlative Light and Electron Microscopy (CLEM) to enable elucidation of cellular and 5 detailed subcellular structures at the pseudoatomic level. Imaging/monitoring single molecules with nanoscale 6 spatiometric resolution within cells is an essential step for investigating the details of cellular processes. Super- 7 resolution and electron microscopy techniques can achieve the resolution required for those purposes and to 8 those ends, fluorescent probes such as fluorescent small molecules, fluorescent proteins (FPs), and quantum 9 dots (QDs) have become essential tools for research and medical diagnostics. 10 Despite the variety of probes that exist, there is an unmet need for a genetically encoded, dual-modality probe 11 suitable for super-resolution Correlated Light and Electron Microscopy (CLEM). Such a probe would have time- 12 integrated single-molecule brightness necessary for super-resolution light microscopy and be electron dense 13 enough to allow visualization/localization by electron microscopy, especially cryogenic electron tomography 14 (CET). To meet those needs, Photon Biosciences is engineering a novel and innovative enabling bioinspired 15 peptide-based probe that has the time-integrated single-molecule brightness and electron density necessary 16 for super-resolution CLEM. The objective of this Phase I project is to rationally engineer a probe to have ≥25 17 Ln3+-phosphorescent centers, which we hypothesize will have the phosphorescence and electron density 18 necessary to surpass current single-modality CLEM probes and then show the probe’s versatility by using it in 19 cryo-luminescence microscopy to guide focused ion beam (FIB) milling of Pseudomonas aeruginosa PAO1 20 expressing a CRISPR-Cas genome-edited engineered construct of our innovative peptide probe fused to the 21 S15 ribosomal protein at native levels as a proof-of-concept for super-resolution CLEM. Aim 1 is to optimize 22 our initial peptide probe via rational engineering for high electron density and brightness. Aim 2 is to develop a 23 multimeric probe from its precursor by concatenation and increase its electron density and brightness further. 24 Aim 3 is to demonstrate proof of concept by cryo-luminescence microscopy. Aim 4 is to demonstrate further 25 proof-of-concept by using the probe for probe-guided FIB milling and tomography. Successful completion of 26 this project will result in an electron dense, time-integrated single molecule brightness, genetically expressible 27 dual modality probe for super-resolution CLEM. ## Key facts - **NIH application ID:** 10823128 - **Project number:** 1R41GM153173-01 - **Recipient organization:** PHOTON BIOSCIENCES, LLC - **Principal Investigator:** CHARLES MARTIN LAWRENCE - **Activity code:** R41 (R01, R21, SBIR, etc.) - **Funding institute:** NIH - **Fiscal year:** 2024 - **Award amount:** $299,812 - **Award type:** 1 - **Project period:** 2024-01-01 → 2025-12-31 ## Primary source NIH RePORTER: https://reporter.nih.gov/project-details/10823128 ## Citation > US National Institutes of Health, RePORTER application 10823128, A Biosinpired Genetically-Expressible Dual-Modality Peptide-Based Probe for Super-Resolution Correlative Light and Electron Microscopy (1R41GM153173-01). Retrieved via AI Analytics 2026-05-26 from https://api.ai-analytics.org/grant/nih/10823128. Licensed CC0. --- *[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*