Source 1primary paper2018International Journal of Molecular Sciences
Toolkit/SPI1085g3 Cys448Ser variant
SPI1085g3 Cys448Ser variant
Also known as: Cys448 of SPI1085g3 replaced with Ser
Taxonomy: Mechanism Branch / Component. Workflows sit above the mechanism and technique branches rather than replacing them.
Summary
SPI1085g3 Cys448Ser variant is a cyanobacteriochrome GAF-domain mutant derived from the Spirulina protein SPI1085g3, generated by replacing Cys448 with Ser. In the reported study, this variant retained the photoswitchable fluorescent behavior of SPI1085g3 while showing slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion.
Usefulness & Problems
Why this is useful
This variant is useful as a modified red/dark-switchable fluorescent biliprotein domain with accelerated recovery to the dark Pr state. The reported combination of photoswitchable fluorescence and faster dark reversion may support applications that benefit from repeated switching cycles or faster reset kinetics, although application-specific validation was not provided in the supplied evidence.
Source:
This novel red/dark-switchable fluorescent biliprotein expands the present repertoire and diversity of photoswitchable fluorescent protein candidates.
Problem solved
The engineering change addresses the need to tune the kinetic and fluorescence properties of SPI1085g3. Specifically, the Cys448Ser substitution improved fluorescence quantum yield slightly and markedly accelerated dark reversion relative to the parent domain.
Taxonomy & Function
Primary hierarchy
Mechanism Branch
Component: A low-level protein part used inside a larger architecture that realizes a mechanism.
Techniques
No technique tags yet.
Target processes
No target processes tagged yet.
Implementation Constraints
The variant was produced by replacing Cys448 with Ser, consistent with site-directed mutagenesis of the SPI1085g3 GAF domain. The supplied evidence does not report construct architecture, expression system, chromophore requirements, purification conditions, or delivery strategy.
The supplied evidence is limited to a single study and a single substitution, with no independent replication described. Quantitative details beyond the relative increase in dark reversion and the statement of slightly improved quantum yield were not provided, and no evidence was supplied on expression, chromophore loading, photostability, cellular performance, or organismal validation.
Validation
Cell-freeBacteriaMammalianMouseHumanTherapeuticIndep. Replication
Supporting Sources
Ranked Claims
SPI1085g3 exhibits moderate dark reversion from the Po state to the Pr state.
exhibited moderate dark reversion (t1/2 = 3.3 min) from the Po state to the Pr state
dark reversion half-life 3.3 min
SPI1085g3 exhibits moderate dark reversion from the Po state to the Pr state.
exhibited moderate dark reversion (t1/2 = 3.3 min) from the Po state to the Pr state
dark reversion half-life 3.3 min
SPI1085g3 exhibits moderate dark reversion from the Po state to the Pr state.
exhibited moderate dark reversion (t1/2 = 3.3 min) from the Po state to the Pr state
dark reversion half-life 3.3 min
SPI1085g3 exhibits moderate dark reversion from the Po state to the Pr state.
exhibited moderate dark reversion (t1/2 = 3.3 min) from the Po state to the Pr state
dark reversion half-life 3.3 min
SPI1085g3 exhibits moderate dark reversion from the Po state to the Pr state.
exhibited moderate dark reversion (t1/2 = 3.3 min) from the Po state to the Pr state
dark reversion half-life 3.3 min
SPI1085g3 exhibits moderate dark reversion from the Po state to the Pr state.
exhibited moderate dark reversion (t1/2 = 3.3 min) from the Po state to the Pr state
dark reversion half-life 3.3 min
SPI1085g3 exhibits moderate dark reversion from the Po state to the Pr state.
exhibited moderate dark reversion (t1/2 = 3.3 min) from the Po state to the Pr state
dark reversion half-life 3.3 min
The Pr state of SPI1085g3 exhibits intense red fluorescence.
The SPI1085g3 Pr state exhibited intense red fluorescence (λmax = 662 nm), with a quantum yield of 0.14.
fluorescence emission maximum 662 nmfluorescence quantum yield 0.14
The Pr state of SPI1085g3 exhibits intense red fluorescence.
The SPI1085g3 Pr state exhibited intense red fluorescence (λmax = 662 nm), with a quantum yield of 0.14.
fluorescence emission maximum 662 nmfluorescence quantum yield 0.14
The Pr state of SPI1085g3 exhibits intense red fluorescence.
The SPI1085g3 Pr state exhibited intense red fluorescence (λmax = 662 nm), with a quantum yield of 0.14.
fluorescence emission maximum 662 nmfluorescence quantum yield 0.14
The Pr state of SPI1085g3 exhibits intense red fluorescence.
The SPI1085g3 Pr state exhibited intense red fluorescence (λmax = 662 nm), with a quantum yield of 0.14.
fluorescence emission maximum 662 nmfluorescence quantum yield 0.14
The Pr state of SPI1085g3 exhibits intense red fluorescence.
The SPI1085g3 Pr state exhibited intense red fluorescence (λmax = 662 nm), with a quantum yield of 0.14.
fluorescence emission maximum 662 nmfluorescence quantum yield 0.14
The Pr state of SPI1085g3 exhibits intense red fluorescence.
The SPI1085g3 Pr state exhibited intense red fluorescence (λmax = 662 nm), with a quantum yield of 0.14.
fluorescence emission maximum 662 nmfluorescence quantum yield 0.14
The Pr state of SPI1085g3 exhibits intense red fluorescence.
The SPI1085g3 Pr state exhibited intense red fluorescence (λmax = 662 nm), with a quantum yield of 0.14.
fluorescence emission maximum 662 nmfluorescence quantum yield 0.14
SPI1085g3 photoconverts from a red-absorbing dark Pr state to an orange-absorbing Po photoproduct state.
SPI1085g3, which exhibited photoconversion from the red-absorbing dark state (Pr, λmax = 642 nm) to the orange-absorbing photoproduct state (Po, λmax = 590 nm)
Po absorption maximum 590 nmPr absorption maximum 642 nm
SPI1085g3 photoconverts from a red-absorbing dark Pr state to an orange-absorbing Po photoproduct state.
SPI1085g3, which exhibited photoconversion from the red-absorbing dark state (Pr, λmax = 642 nm) to the orange-absorbing photoproduct state (Po, λmax = 590 nm)
Po absorption maximum 590 nmPr absorption maximum 642 nm
SPI1085g3 photoconverts from a red-absorbing dark Pr state to an orange-absorbing Po photoproduct state.
SPI1085g3, which exhibited photoconversion from the red-absorbing dark state (Pr, λmax = 642 nm) to the orange-absorbing photoproduct state (Po, λmax = 590 nm)
Po absorption maximum 590 nmPr absorption maximum 642 nm
SPI1085g3 photoconverts from a red-absorbing dark Pr state to an orange-absorbing Po photoproduct state.
SPI1085g3, which exhibited photoconversion from the red-absorbing dark state (Pr, λmax = 642 nm) to the orange-absorbing photoproduct state (Po, λmax = 590 nm)
Po absorption maximum 590 nmPr absorption maximum 642 nm
SPI1085g3 photoconverts from a red-absorbing dark Pr state to an orange-absorbing Po photoproduct state.
SPI1085g3, which exhibited photoconversion from the red-absorbing dark state (Pr, λmax = 642 nm) to the orange-absorbing photoproduct state (Po, λmax = 590 nm)
Po absorption maximum 590 nmPr absorption maximum 642 nm
SPI1085g3 photoconverts from a red-absorbing dark Pr state to an orange-absorbing Po photoproduct state.
SPI1085g3, which exhibited photoconversion from the red-absorbing dark state (Pr, λmax = 642 nm) to the orange-absorbing photoproduct state (Po, λmax = 590 nm)
Po absorption maximum 590 nmPr absorption maximum 642 nm
SPI1085g3 photoconverts from a red-absorbing dark Pr state to an orange-absorbing Po photoproduct state.
SPI1085g3, which exhibited photoconversion from the red-absorbing dark state (Pr, λmax = 642 nm) to the orange-absorbing photoproduct state (Po, λmax = 590 nm)
Po absorption maximum 590 nmPr absorption maximum 642 nm
SPI1085g3 fluorescence is switched off by red light irradiation and increases in the dark.
The fluorescence was switched off by red light irradiation and increased in the dark.
SPI1085g3 fluorescence is switched off by red light irradiation and increases in the dark.
The fluorescence was switched off by red light irradiation and increased in the dark.
SPI1085g3 fluorescence is switched off by red light irradiation and increases in the dark.
The fluorescence was switched off by red light irradiation and increased in the dark.
SPI1085g3 fluorescence is switched off by red light irradiation and increases in the dark.
The fluorescence was switched off by red light irradiation and increased in the dark.
SPI1085g3 fluorescence is switched off by red light irradiation and increases in the dark.
The fluorescence was switched off by red light irradiation and increased in the dark.
SPI1085g3 fluorescence is switched off by red light irradiation and increases in the dark.
The fluorescence was switched off by red light irradiation and increased in the dark.
SPI1085g3 fluorescence is switched off by red light irradiation and increases in the dark.
The fluorescence was switched off by red light irradiation and increased in the dark.
SPI1085g3 is a novel red/dark-switchable fluorescent biliprotein and a photoswitchable fluorescent protein candidate.
This novel red/dark-switchable fluorescent biliprotein expands the present repertoire and diversity of photoswitchable fluorescent protein candidates.
SPI1085g3 is a novel red/dark-switchable fluorescent biliprotein and a photoswitchable fluorescent protein candidate.
This novel red/dark-switchable fluorescent biliprotein expands the present repertoire and diversity of photoswitchable fluorescent protein candidates.
SPI1085g3 is a novel red/dark-switchable fluorescent biliprotein and a photoswitchable fluorescent protein candidate.
This novel red/dark-switchable fluorescent biliprotein expands the present repertoire and diversity of photoswitchable fluorescent protein candidates.
SPI1085g3 is a novel red/dark-switchable fluorescent biliprotein and a photoswitchable fluorescent protein candidate.
This novel red/dark-switchable fluorescent biliprotein expands the present repertoire and diversity of photoswitchable fluorescent protein candidates.
SPI1085g3 is a novel red/dark-switchable fluorescent biliprotein and a photoswitchable fluorescent protein candidate.
This novel red/dark-switchable fluorescent biliprotein expands the present repertoire and diversity of photoswitchable fluorescent protein candidates.
SPI1085g3 is a novel red/dark-switchable fluorescent biliprotein and a photoswitchable fluorescent protein candidate.
This novel red/dark-switchable fluorescent biliprotein expands the present repertoire and diversity of photoswitchable fluorescent protein candidates.
SPI1085g3 is a novel red/dark-switchable fluorescent biliprotein and a photoswitchable fluorescent protein candidate.
This novel red/dark-switchable fluorescent biliprotein expands the present repertoire and diversity of photoswitchable fluorescent protein candidates.
The SPI1085g3 Cys448Ser variant has slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion than wild type.
Replacement of Cys448 of SPI1085g3 with Ser resulted in a slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion (t1/2 = 15.2 s) than that of the wild type.
dark reversion half-life 15.2 sdark reversion rate change versus wild type nearly 13-fold faster
The SPI1085g3 Cys448Ser variant has slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion than wild type.
Replacement of Cys448 of SPI1085g3 with Ser resulted in a slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion (t1/2 = 15.2 s) than that of the wild type.
dark reversion half-life 15.2 sdark reversion rate change versus wild type nearly 13-fold faster
The SPI1085g3 Cys448Ser variant has slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion than wild type.
Replacement of Cys448 of SPI1085g3 with Ser resulted in a slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion (t1/2 = 15.2 s) than that of the wild type.
dark reversion half-life 15.2 sdark reversion rate change versus wild type nearly 13-fold faster
The SPI1085g3 Cys448Ser variant has slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion than wild type.
Replacement of Cys448 of SPI1085g3 with Ser resulted in a slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion (t1/2 = 15.2 s) than that of the wild type.
dark reversion half-life 15.2 sdark reversion rate change versus wild type nearly 13-fold faster
The SPI1085g3 Cys448Ser variant has slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion than wild type.
Replacement of Cys448 of SPI1085g3 with Ser resulted in a slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion (t1/2 = 15.2 s) than that of the wild type.
dark reversion half-life 15.2 sdark reversion rate change versus wild type nearly 13-fold faster
The SPI1085g3 Cys448Ser variant has slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion than wild type.
Replacement of Cys448 of SPI1085g3 with Ser resulted in a slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion (t1/2 = 15.2 s) than that of the wild type.
dark reversion half-life 15.2 sdark reversion rate change versus wild type nearly 13-fold faster
The SPI1085g3 Cys448Ser variant has slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion than wild type.
Replacement of Cys448 of SPI1085g3 with Ser resulted in a slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion (t1/2 = 15.2 s) than that of the wild type.
dark reversion half-life 15.2 sdark reversion rate change versus wild type nearly 13-fold faster
Approval Evidence
1 source1 linked approval claimfirst-pass slug spi1085g3-cys448ser-variant
Replacement of Cys448 of SPI1085g3 with Ser resulted in a slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion
Source:
variant effectsupports
The SPI1085g3 Cys448Ser variant has slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion than wild type.
Replacement of Cys448 of SPI1085g3 with Ser resulted in a slightly improved fluorescence quantum yield and nearly 13-fold faster dark reversion (t1/2 = 15.2 s) than that of the wild type.
Source:
Comparisons
Source-backed strengths
The key reported strengths are a slight increase in fluorescence quantum yield and nearly 13-fold faster dark reversion compared with SPI1085g3. The parent protein is reported to photoconvert from a red-absorbing Pr state to an orange-absorbing Po state, and its Pr state exhibits intense red fluorescence, supporting the interpretation that the variant modifies an already photoswitchable fluorescent scaffold.
Ranked Citations
- 1.