Browse
Submit Data
Databases
API
Help

Dataset Information

19 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

A photoactive semisynthetic metalloenzyme exhibits complete selectivity for CO2 reduction in water.

ABSTRACT: A series of artificial metalloenzymes containing a ruthenium chromophore and [NiII(cyclam)]2+, both incorporated site-selectively, have been constructed within an azurin protein scaffold. These light-driven, semisynthetic enzymes do not evolve hydrogen, thus displaying complete selectivity for CO2 reduction to CO. Electrostatic effects rather than direct excited-state electron transfer dominate the ruthenium photophysics, suggesting that intramolecular electron transfer from photogenerated RuI to [NiII(cyclam)]2+ represents the first step in catalysis. Stern-Volmer analyses rationalize the observation that ascorbate is the only sacrificial electron donor that supports turnover. Collectively, these results highlight the important interplay of elements that must be considered when developing and characterizing molecular catalysts.

SUBMITTER: Schneider CR

PROVIDER: S-EPMC5934327 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

A photoactive semisynthetic metalloenzyme exhibits complete selectivity for CO<sub>2</sub> reduction in water.

Schneider Camille R CR Manesis Anastasia C AC Stevenson Michael J MJ Shafaat Hannah S HS

Chemical communications (Cambridge, England) 20180501 37

A series of artificial metalloenzymes containing a ruthenium chromophore and [NiII(cyclam)]2+, both incorporated site-selectively, have been constructed within an azurin protein scaffold. These light-driven, semisynthetic enzymes do not evolve hydrogen, thus displaying complete selectivity for CO2 reduction to CO. Electrostatic effects rather than direct excited-state electron transfer dominate the ruthenium photophysics, suggesting that intramolecular electron transfer from photogenerated RuI t ...[more]

PMID: 29675518

Similar Datasets

An internal electron reservoir enhances catalytic CO2 reduction by a semisynthetic enzyme.

Project description:The development of an artificial metalloenzyme for CO2 reduction is described. The small-molecule catalyst [Ni(II)(cyclam)](2+) has been incorporated within azurin. Selectivity for CO generation over H(+) reduction is enhanced within the protein environment, while the azurin active site metal impacts the electrochemical overpotential and photocatalytic activity. The enhanced catalysis observed for copper azurin suggests an important role for intramolecular electron transfer, analogous to native CO2 reducing enzymes.

| S-EPMC4977188 | biostudies-literature

Substrate selectivity for semisynthetic CK2 proteins

Project description:This SuperSeries is composed of the SubSeries listed below.

2011-10-25 | GSE33151 | GEO

Substrate selectivity for semisynthetic CK2 proteins

Project description:This SuperSeries is composed of the following subset Series: GSE33149: Substrate selectivity for semisynthetic CK2 proteins with various posttranslational modifications GSE33150: Substrate selectivity for semisynthetic CK2 proteins with Pin1 Refer to individual Series

2011-10-24 | E-GEOD-33151 | biostudies-arrayexpress

Substrate selectivity for semisynthetic CK2 proteins with Pin1

2011-10-25 | GSE33150 | GEO

Investigating the selectivity of metalloenzyme inhibitors.

Project description:The inhibitory activity of a broad group of known metalloenzyme inhibitors against a panel of metalloenzymes was evaluated. Clinically approved inhibitors were selected as well as several other reported metalloprotein inhibitors in order to represent a broad range of metal binding groups (MBGs), including hydroxamic acid, carboxylate, hydroxypyridinonate, thiol, and N-hydroxyurea functional groups. A panel of metalloenzymes, including carbonic anhydrase (hCAII), several matrix metalloproteinases (MMPs), angiotensin converting enzyme (ACE), histone deacetylase (HDAC-2), and tyrosinase (TY), was selected based on their clinical importance for a range of pathologies. In addition, each inhibitor was evaluated for its ability to remove Fe(3+) from holo-transferrin to gauge the ability of the inhibitors to access Fe(3+) from a primary transport protein. The results show that the metalloenzyme inhibitors are quite selective for their intended targets, suggesting that despite their ability to bind metal ions, metalloprotein inhibitors are not prone to widespread off-target enzyme inhibition activity.

| S-EPMC3880651 | biostudies-literature

Substrate selectivity for semisynthetic CK2 proteins with Pin1

Project description:Protein Ser/Thr kinase CK2 is involved in a myriad of cellular processes including cell growth and proliferation by phosphorylating hundreds of substrates, yet the regulation process of CK2 function is poorly understood. The CK2 catalytic subunit, CK2α, is phosphorylated at Thr344 and phosphorylation on the C-terminal tail of CK2α is required for interaction with Pin1 protein. The substrate selectivity for protein kinase CK2α was examined by performing kinase assays on protein microarrays spotted with 17,000 human proteins. Semisynthetic CK2α proteins were prepared to contain an unmodified C-terminal tail or phospho-Thr (pThr) at T344. These semisynthetic proteins were used to determine if the phosphorylation-dependent interaction of CK2α with Pin1 can modulate the substrate selectivity for CK2. The different semisynthetic CK2α proteins (unmodified and pThr344) were tested alone and in the presence of the recombinant Pin1 protein. Pin1 has been shown to interaction with CK2α only when CK2α is phoshorylated on its C-terminal site (including Thr344). In the study presented here, kinase assays were performed using two different semisynthetic CK2α proteins: unmodified C-terminal tail and phospho-Thr (pThr) at 344. The semisynthetic proteins were each tested alone and in the presence of the recombinant Pin1 protein. There were four different kinase conditions and each condition was performed in duplicate.

2011-10-24 | E-GEOD-33150 | biostudies-arrayexpress

Substrate selectivity of semisynthetic Akt with pSer473 or O-GlcNAcSer473

Project description:Akt is a Ser/Thr protein kinase that regulates cell growth, metabolism and is considered a therapeutic target for cancer. Regulation of Akt by membrane recruitment and post-translational modifications (PTMs) has been extensively studied. The most well-established mechanism for cellular Akt activation involves phosphorylation on its activation loop on Thr308 by PDK1 and on its C-terminal tail on Ser473 by mTORC2. Other C-terminal tail PTMs have been identified, but their functional impacts have not been well-characterized. We use expressed protein ligation (EPL) as a tool to produce semisynthetic Akt proteins to dissect the enzymatic functions of these PTMs. We performed kinase assays employing human protein microarrays to investigate global substrate specificity of Akt, comparing phosphorylated vs. O-GlcNAcylated Ser473 forms.

2021-08-13 | GSE181983 | GEO

Substrate selectivity for semisynthetic CK2 proteins with various posttranslational modifications

Project description:Protein Ser/Thr kinase CK2 is involved in a myriad of cellular processes including cell growth and proliferation by phosphorylating hundreds of substrates, yet the regulation process of CK2 function is poorly understood. The CK2 catalytic subunit, CK2α, is modified by O-GlcNAc on Ser347 proximal to a Cdk1 phosphorylation site at Thr344 on the same protein. The substrate selectivity for protein kinase CK2 was examined by performing kinase assays on protein microarrays spotted with 17,000 human proteins. Semisynthetic CK2α proteins were prepared to contain an unmodified C-terminal tail, S-GlcNAc-Serine at S347, or Pfa (non-hyrdolyzeable phosphomimic) at T344. These semisynthetic proteins were used to determine if the posttranslational modifications on CK2 alpha modulate the substrate selectivity for this pleiotropic kinase. The different semisynthetic CK2α proteins were tested alone and in the presence of the regulatory subunit CK2β since it is known that the CK2α subunit is active both in its isolated state and in the heterotetrameric state formed in the presence of the regulatory beta subunit. The CK2β subunit has been shown to modulate CK2 activity with some substrates and not others.

2011-10-25 | GSE33149 | GEO

Substrate selectivity for semisynthetic CK2 proteins with various posttranslational modifications

Project description:Protein Ser/Thr kinase CK2 is involved in a myriad of cellular processes including cell growth and proliferation by phosphorylating hundreds of substrates, yet the regulation process of CK2 function is poorly understood. The CK2 catalytic subunit, CK2α, is modified by O-GlcNAc on Ser347 proximal to a Cdk1 phosphorylation site at Thr344 on the same protein. The substrate selectivity for protein kinase CK2 was examined by performing kinase assays on protein microarrays spotted with 17,000 human proteins. Semisynthetic CK2α proteins were prepared to contain an unmodified C-terminal tail, S-GlcNAc-Serine at S347, or Pfa (non-hyrdolyzeable phosphomimic) at T344. These semisynthetic proteins were used to determine if the posttranslational modifications on CK2 alpha modulate the substrate selectivity for this pleiotropic kinase. The different semisynthetic CK2α proteins were tested alone and in the presence of the regulatory subunit CK2β since it is known that the CK2α subunit is active both in its isolated state and in the heterotetrameric state formed in the presence of the regulatory beta subunit. The CK2β subunit has been shown to modulate CK2 activity with some substrates and not others. In the study presented here, kinase assays were performed using three different semisynthetic CK2 alpha proteins: unmodified C-terminal tail; S-GlcNAc-Ser at 347; and Pfa (phosphomimic) at 344. The semisynthetic proteins were each tested alone and in the presence of the regualatory CK2 beta subunit. There were six different kinase conditions and each condition was performed in duplicate and one no kinase control was performed to eliminate autophorylated proteins.

2011-10-24 | E-GEOD-33149 | biostudies-arrayexpress

A de?novo designed metalloenzyme for the hydration of CO2.

Project description:Protein design will ultimately allow for the creation of artificial enzymes with novel functions and unprecedented stability. To test our current mastery of nature's approach to catalysis, a Zn(II) metalloenzyme was prepared using de?novo design. ?3DH3 folds into a stable single-stranded three-helix bundle and binds Zn(II) with high affinity using His3 O coordination. The resulting metalloenzyme catalyzes the hydration of CO2 better than any small molecule model of carbonic anhydrase and with an efficiency within 1400-fold of the fastest carbonic anhydrase isoform, CAII, and 11-fold of CAIII.

| S-EPMC4107010 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data