6UKK

Crystal Structure of a Domain-swapped Fluorogen Activating Protein DiB3 Dimer

Summary for 6UKK

• Entry DOI: 10.2210/pdb6ukk/pdb
• Descriptor: Outer membrane lipoprotein Blc, SODIUM ION (3 entities in total)
• Functional Keywords: lipocalin, beta barrel, domain-swapped protein, fluorogen activating protein, fluorescent protein
• Biological source: Escherichia coli
• Total number of polymer chains: 1
• Total formula weight: 20250.61

Authors

Bozhanova, N.G.,Meiler, J. (deposition date: 2019-10-05, release date: 2020-07-08, Last modification date: 2023-10-11)

Primary citation

Bozhanova, N.G.,Gavrikov, A.S.,Mishin, A.S.,Meiler, J.
DiB-splits: nature-guided design of a novel fluorescent labeling split system.
Sci Rep, 10:11049-11049, 2020

PubMed Abstract: Fluorogen-activating proteins (FAPs) are innovative fluorescent probes combining advantages of genetically-encoded proteins such as green fluorescent protein and externally added fluorogens that allow for highly tunable and on demand fluorescent signaling. Previously, a panel of green- and red-emitting FAPs has been created from bacterial lipocalin Blc (named DiBs). Here we present a rational design as well as functional and structural characterization of the first self-assembling FAP split system, DiB-splits. This new system decreases the size of the FAP label to ~8-12 kDa while preserving DiBs' unique properties: strong increase in fluorescence intensity of the chromophore upon binding, binding affinities to the chromophore in nanomolar to low micromolar range, and high photostability of the protein-ligand complex. These properties allow for use of DiB-splits for wide-field, confocal, and super-resolution fluorescence microscopy. DiB-splits also represent an attractive starting point for further design of a protein-protein interaction detection system as well as novel FAP-based sensors.

PubMed: 32632329
DOI: 10.1038/s41598-020-67095-2

Experimental method

X-RAY DIFFRACTION (1.6 Å)