Severity: Warning
Message: Undefined array key "choices"
Filename: controllers/Detail.php
Line Number: 249
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 249
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 249
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 249
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: 8192
Message: strpos(): Passing null to parameter #1 ($haystack) of type string is deprecated
Filename: models/Detail_model.php
Line Number: 71
Backtrace:
File: /var/www/html/application/models/Detail_model.php
Line: 71
Function: strpos
File: /var/www/html/application/controllers/Detail.php
Line: 252
Function: insertAPISummary
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: 8192
Message: str_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated
Filename: helpers/my_audit_helper.php
Line Number: 8919
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 8919
Function: str_replace
File: /var/www/html/application/controllers/Detail.php
Line: 255
Function: formatAIDetailSummary
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Undefined array key "choices"
Filename: controllers/Detail.php
Line Number: 256
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 256
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 256
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 256
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 256
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 256
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Undefined array key "usage"
Filename: controllers/Detail.php
Line Number: 257
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 257
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 257
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 257
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Undefined array key "usage"
Filename: controllers/Detail.php
Line Number: 258
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 258
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 258
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 258
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Undefined array key "usage"
Filename: controllers/Detail.php
Line Number: 259
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 259
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 259
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 259
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Undefined array key "usage"
Filename: controllers/Detail.php
Line Number: 260
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 260
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 260
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 260
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 260
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 260
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Peroxiredoxins use a variety of thiols to rapidly reduce hydroperoxides and peroxynitrite. While the oxidation kinetics of peroxiredoxins have been studied in great detail, enzyme-specific differences regarding peroxiredoxin reduction and the overall rate-limiting step under physiological conditions often remain to be deciphered. The 1-Cys peroxiredoxin 5 homolog PfAOP from the malaria parasite Plasmodium falciparum is an established model enzyme for glutathione/glutaredoxin-dependent peroxiredoxins. Here, we reconstituted the catalytic cycle of PfAOP in vitro and analyzed the reaction between oxidized PfAOP and reduced glutathione (GSH) using molecular docking and stopped-flow measurements. Molecular docking revealed that oxidized PfAOP has to adopt a locally unfolded conformation to react with GSH. Furthermore, we determined a second-order rate constant of 6 × 10 M s at 25°C and thermodynamic activation parameters ΔH , ΔS , and ΔG of 39.8 kJ/mol, -0.8 J/mol, and 40.0 kJ/mol, respectively. The gain-of-function mutant PfAOP had almost identical reaction parameters. Taking into account physiological hydroperoxide and GSH concentrations, we suggest (a) that the reaction between oxidized PfAOP and GSH might be even faster than the formation of the sulfenic acid in vivo, and (b) that conformational changes are likely rate limiting for PfAOP catalysis. In summary, we characterized and quantified the reaction between GSH and the model enzyme PfAOP, thus providing detailed insights regarding the reactivity of its sulfenic acid and the versatile chemistry of peroxiredoxins.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8994508 | PMC |
http://dx.doi.org/10.1002/pro.4290 | DOI Listing |
Protein Sci
May 2022
Faculty of Chemistry, TU Kaiserslautern, Kaiserslautern, Germany.
Peroxiredoxins use a variety of thiols to rapidly reduce hydroperoxides and peroxynitrite. While the oxidation kinetics of peroxiredoxins have been studied in great detail, enzyme-specific differences regarding peroxiredoxin reduction and the overall rate-limiting step under physiological conditions often remain to be deciphered. The 1-Cys peroxiredoxin 5 homolog PfAOP from the malaria parasite Plasmodium falciparum is an established model enzyme for glutathione/glutaredoxin-dependent peroxiredoxins.
View Article and Find Full Text PDFJ Microbiol Biotechnol
January 2021
South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences; Key Lab of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs of the People's Republic of China, Guangzhou 510300, P. R. China.
Due to the potential of antioxidants to scavenge free radicals in human body, it is important to be able to prepare antioxidant peptides that meet the industrial requirements for cosmetics and food. Here, we determined in vivo/in vitro activities of antioxidant peptide from (PFAOP) prepared by bio-fermentation method. The antioxidant property test results showed the DPPH, hydroxyl, superoxide radical-scavenging, and cellular antioxidant activity.
View Article and Find Full Text PDFRedox Biol
April 2018
University of Kaiserslautern, Erwin-Schrödinger-Straße 54, D-67663 Kaiserslautern, Germany; Department of Parasitology, Ruprecht-Karls University, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany. Electronic address:
Redox-sensitive green fluorescent protein 2 (roGFP2) is a valuable tool for redox measurements in living cells. Here, we demonstrate that roGFP2 can also be used to gain mechanistic insights into redox catalysis in vivo. In vitro enzyme properties such as the rate-limiting reduction of wild type and mutant forms of the model peroxiredoxin PfAOP are shown to correlate with the ratiometrically measured degree of oxidation of corresponding roGFP2 fusion proteins.
View Article and Find Full Text PDFSci Rep
June 2017
Department of Parasitology, Ruprecht-Karls University, Im Neuenheimer Feld 324, D-69120, Heidelberg, Germany.
Artemisinins are the current mainstay of malaria chemotherapy. Their exact mode of action is an ongoing matter of debate, and several factors have recently been reported to affect an early stage of artemisinin resistance of the most important human malaria parasite Plasmodium falciparum. Here, we identified a locus on chromosome 7 that affects the artemisinin susceptibility of P.
View Article and Find Full Text PDFJ Mol Biol
March 2005
Department of Biochemistry and Biophysics, Oregon State University, 2011 ALS, Corvallis, OR 97331-7305, USA.
Plasmodium falciparum, the causative agent of malaria, is sensitive to oxidative stress and therefore the family of antioxidant enzymes, peroxiredoxins (Prxs) represent a target for antimalarial drug design. We present here the 1.8 A resolution crystal structure of P.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!