Chromophore binding to two cysteines increases quantum yield of near-infrared fluorescent proteins

dc.contributor.authorBuhrke, David
dc.contributor.authorTavraz, Neslihan N.
dc.contributor.authorShcherbakova, Daria M.
dc.contributor.authorSauthof, Luisa
dc.contributor.authorMoldenhauer, Marcus
dc.contributor.authorVélazquez Escobar, Francisco
dc.contributor.authorVerkhusha, Vladislav V.
dc.contributor.authorHildebrandt, Peter
dc.contributor.authorFriedrich, Thomas
dc.date.accessioned2019-02-18T11:39:33Z
dc.date.available2019-02-18T11:39:33Z
dc.date.issued2019-02-12
dc.description.abstractPhytochromes are red/far-red light sensing photoreceptors employing linear tetrapyrroles as chromophores, which are covalently bound to a cysteine (Cys) residue in the chromophore-binding domain (CBD, composed of a PAS and a GAF domain). Recently, near-infrared (NIR) fluorescent proteins (FPs) engineered from bacterial phytochromes binding biliverdin IXα (BV), such as the iRFP series, have become invaluable probes for multicolor fluorescence microscopy and in vivo imaging. However, all current NIR FPs suffer from relatively low brightness. Here, by combining biochemical, spectroscopic and resonance Raman (RR) assays, we purified and characterized an iRFP variant that contains a BV chromophore simultaneously bound to two cysteines. This protein with the unusual double-Cys attached BV showed the highest fluorescence quantum yield (FQY) of 16.6% reported for NIR FPs, whereas the initial iRFP appeared to be a mixture of species with a mean FQY of 11.1%. The purified protein was also characterized with 1.3-fold higher extinction coefficient that together with FQY resulted in almost two-fold brighter fluorescence than the original iRFP as isolated. This work shows that the high FQY of iRFPs with two cysteines is a direct consequence of the double attachment. The PAS-Cys, GAF-Cys and double-Cys attachment each entails distinct configurational constraints of the BV adduct, which can be identified by distinct RR spectroscopic features, i.e. the marker band including the C=C stretching coordinate of the ring A-B methine bridge, which was previously identified as being characteristic for rigid chromophore embedment and high FQY. Our findings can be used to rationally engineer iRFP variants with enhanced FQYs.en
dc.description.sponsorshipDFG, 325093850, Open Access Publizieren 2017 - 2018 / Technische Universität Berlinde
dc.description.sponsorshipBMBF, 01DJ15007, Carotenoidbindende photoschaltbare Proteine: Lichtinduzierte Dynamik und Anwendungen in modernen mikroskopischen Verfahrende
dc.description.sponsorshipDFG, 53182490, EXC 314: Unifying Concepts in Catalysisde
dc.description.sponsorshipDFG, 221545957, SFB 1078: Proteinfunktion durch Protonierungsdynamikde
dc.identifier.eissn2045-2322
dc.identifier.urihttps://depositonce.tu-berlin.de/handle/11303/9125
dc.identifier.urihttp://dx.doi.org/10.14279/depositonce-8214
dc.language.isoenen
dc.relation.ispartof10.14279/depositonce-8309
dc.rights.urihttps://creativecommons.org/licenses/by/4.0/en
dc.subject.ddc540 Chemie und zugeordnete Wissenschaftende
dc.subject.ddc600 Technikde
dc.subject.otherchromophore bindingen
dc.subject.otherfluorescenceen
dc.subject.otherproteinen
dc.titleChromophore binding to two cysteines increases quantum yield of near-infrared fluorescent proteinsen
dc.typeArticleen
dc.type.versionpublishedVersionen
dcterms.bibliographicCitation.articlenumber1866en
dcterms.bibliographicCitation.doi10.1038/s41598-018-38433-2en
dcterms.bibliographicCitation.journaltitleScientific Reportsen
dcterms.bibliographicCitation.originalpublishernameNature Publishing Groupen
dcterms.bibliographicCitation.originalpublisherplaceLondonen
dcterms.bibliographicCitation.volume9en
tub.accessrights.dnbfreeen
tub.affiliationFak. 2 Mathematik und Naturwissenschaften::Inst. Chemie::FG Bioenergetikde
tub.affiliation.facultyFak. 2 Mathematik und Naturwissenschaftende
tub.affiliation.groupFG Bioenergetikde
tub.affiliation.instituteInst. Chemiede
tub.publisher.universityorinstitutionTechnische Universität Berlinen

Files

Original bundle
Now showing 1 - 1 of 1
Loading…
Thumbnail Image
Name:
s41598-018-38433-2.pdf
Size:
2.09 MB
Format:
Adobe Portable Document Format
Description:
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
5.75 KB
Format:
Item-specific license agreed upon to submission
Description:

Collections