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Title: LDRD final report on imaging self-organization of proteins in membranes by photocatalytic nano-tagging.

Abstract

We have developed a new nanotagging technology for detecting and imaging the self-organization of proteins and other components of membranes at nanometer resolution for the purpose of investigating cell signaling and other membrane-mediated biological processes. We used protein-, lipid-, or drug-bound porphyrin photocatalysts to grow in-situ nanometer-sized metal particles, which reveal the location of the porphyrin-labeled molecules by electron microscopy. We initially used photocatalytic nanotagging to image assembled multi-component proteins and to monitor the distribution of lipids and porphyrin labels in liposomes. For example, by exchanging the heme molecules in hemoproteins with a photocatalytic tin porphyrin, a nanoparticle was grown at each heme site of the protein. The result obtained from electron microscopy for a tagged multi-subunit protein such as hemoglobin is a symmetric constellation of a specific number of nanoparticle tags, four in the case of the hemoglobin tetramer. Methods for covalently linking photocatalytic porphyrin labels to lipids and proteins were also developed to detect and image the self-organization of lipids, protein-protein supercomplexes, and membrane-protein complexes. Procedures for making photocatalytic porphyrin-drug, porphyrin-lipid, and porphyrin-protein hybrids for non-porphyrin-binding proteins and membrane components were pursued and the first porphyrin-labeled lipids was investigated in liposomal membrane models. Our photocatalytic nanotagging technique maymore » ultimately allow membrane self-organization and cell signaling processes to be imaged in living cells. Fluorescence and plasmonic spectra of the tagged proteins might also provide additional information about protein association and membrane organization. In addition, a porphyrin-aspirin or other NSAID hybrid may be used to grow metal nanotags for the pharmacologically important COX enzymes in membranes so that the distribution of the protein can be imaged at the nanometer scale.« less

Authors:
; ; ; ;
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
875973
Report Number(s):
SAND2005-6948
TRN: US200604%%280
DOE Contract Number:  
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; DISTRIBUTION; ELECTRON MICROSCOPY; ENZYMES; FLUORESCENCE; HEME; HEMOGLOBIN; LIPIDS; LIPOSOMES; MEMBRANES; MONITORS; PORPHYRINS; PROTEINS; RESOLUTION; SPECTRA; Cell membranes.; Protein-analysis.; Membranes.

Citation Formats

Zavadil, Kevin Robert, Shelnutt, John Allen, Sasaki, Darryl Yoshio, Song, Yujiang, and Medforth, Craig J. LDRD final report on imaging self-organization of proteins in membranes by photocatalytic nano-tagging.. United States: N. p., 2005. Web. doi:10.2172/875973.
Zavadil, Kevin Robert, Shelnutt, John Allen, Sasaki, Darryl Yoshio, Song, Yujiang, & Medforth, Craig J. LDRD final report on imaging self-organization of proteins in membranes by photocatalytic nano-tagging.. United States. doi:10.2172/875973.
Zavadil, Kevin Robert, Shelnutt, John Allen, Sasaki, Darryl Yoshio, Song, Yujiang, and Medforth, Craig J. Tue . "LDRD final report on imaging self-organization of proteins in membranes by photocatalytic nano-tagging.". United States. doi:10.2172/875973. https://www.osti.gov/servlets/purl/875973.
@article{osti_875973,
title = {LDRD final report on imaging self-organization of proteins in membranes by photocatalytic nano-tagging.},
author = {Zavadil, Kevin Robert and Shelnutt, John Allen and Sasaki, Darryl Yoshio and Song, Yujiang and Medforth, Craig J.},
abstractNote = {We have developed a new nanotagging technology for detecting and imaging the self-organization of proteins and other components of membranes at nanometer resolution for the purpose of investigating cell signaling and other membrane-mediated biological processes. We used protein-, lipid-, or drug-bound porphyrin photocatalysts to grow in-situ nanometer-sized metal particles, which reveal the location of the porphyrin-labeled molecules by electron microscopy. We initially used photocatalytic nanotagging to image assembled multi-component proteins and to monitor the distribution of lipids and porphyrin labels in liposomes. For example, by exchanging the heme molecules in hemoproteins with a photocatalytic tin porphyrin, a nanoparticle was grown at each heme site of the protein. The result obtained from electron microscopy for a tagged multi-subunit protein such as hemoglobin is a symmetric constellation of a specific number of nanoparticle tags, four in the case of the hemoglobin tetramer. Methods for covalently linking photocatalytic porphyrin labels to lipids and proteins were also developed to detect and image the self-organization of lipids, protein-protein supercomplexes, and membrane-protein complexes. Procedures for making photocatalytic porphyrin-drug, porphyrin-lipid, and porphyrin-protein hybrids for non-porphyrin-binding proteins and membrane components were pursued and the first porphyrin-labeled lipids was investigated in liposomal membrane models. Our photocatalytic nanotagging technique may ultimately allow membrane self-organization and cell signaling processes to be imaged in living cells. Fluorescence and plasmonic spectra of the tagged proteins might also provide additional information about protein association and membrane organization. In addition, a porphyrin-aspirin or other NSAID hybrid may be used to grow metal nanotags for the pharmacologically important COX enzymes in membranes so that the distribution of the protein can be imaged at the nanometer scale.},
doi = {10.2172/875973},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}

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