Studies of the interactions of dienelactone hydrolase (DLH) and its mutants with both E and Z dienelactone substrates show that the enzyme exhibits two different conformational responses specific for hydrolysis of each of its substrate isomers. DLH facilitates hydrolysis of the Z dienelactone through an unusual charge-relay system that is initiated by interaction between the substrate carboxylate and an enzyme arginine residue that activates an otherwise non-nucleophilic cysteine. The E dienelactone does not display this substrate-arginine binding interaction, but instead induces an alternate conformational response that promotes hydrolysis. Furthermore, the substitution of cysteine 123 for serine (C123S) in DLH, instead of inactivating the enzyme as is typical for this active-site mutation, changes the catalysis from substrate hydrolysis to isomerisation. This is due to the deacylation of the acyl-enzyme intermediates being much slower, thereby increasing their lifetimes and allowing for their interconversion through isomerisation, followed by relactonisation.
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Enzyme Microb Technol
October 2024
Centro de Ciências Naturais e Humanas, Universidade Federal do ABC (UFABC),Santo André, SP, Brazil. Electronic address:
Dienelactone hydrolase (DLH) is one of numerous hydrolytic enzymes with an α/β-hydrolase fold, which catalyze the hydrolysis of dienelactone to maleylacetate. The DLHs share remarkably similar tertiary structures and a conserved arrangement of catalytic residues. This study presents the crystal structure and comprehensive functional characterization of a novel thermostable DLH from the bacterium Hydrogenobacter thermophilus (HtDLH).
View Article and Find Full Text PDFBraz J Microbiol
September 2024
School of Biotechnology, Gautam Buddha University, Greater Noida, U.P., India.
The overwhelming use of PET plastic in various day-to-day activities led to the voluminous increase in PET waste and growing environmental hazards. A plethora of methods have been used that are associated with secondary pollutants. Therefore, microbial degradation of PET provides a sustainable approach due to its versatile metabolic diversity and capacity.
View Article and Find Full Text PDFPlants (Basel)
March 2024
Institute for Organismic and Molecular Evolution (iomE), Johannes Gutenberg University, 55128 Mainz, Germany.
Understanding non-target-site resistance (NTSR) to herbicides represents a pressing challenge as NTSR is widespread in many weeds. Using giant duckweed () as a model, we systematically investigated genetic and molecular mechanisms of diquat resistance, which can only be achieved via NTSR. Quantifying the diquat resistance of 138 genotypes, we revealed an 8.
View Article and Find Full Text PDFSci Rep
January 2024
Department of Microbiology and Biotechnology, Institute of Plant Science and Microbiology, University of Hamburg, Ohnhorststr.18, 22609, Hamburg, Germany.
Cell Rep
November 2023
Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China; Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai 200032, China; Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China. Electronic address:
Aerobic glycolysis is critical for cancer progression and can be exploited in cancer therapy. Here, we report that the human carboxymethylenebutenolidase homolog (carboxymethylenebutenolidase-like [CMBL]) acts as a tumor suppressor by reprogramming glycolysis in colorectal cancer (CRC). The anti-cancer action of CMBL is mediated through its interactions with the E3 ubiquitin ligase TRIM25 and the glycolytic enzyme phosphofructokinase-1 platelet type (PFKP).
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