Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.12.7.2 (
hydrogenase
)
3,522
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Oxidative stress conditions lead to enzymatic and non-enzymatic unsaturated fatty acid-initiated lipid peroxidation reactions. One exacerbating product is lipid hydroperoxide (LOOH) which itself promotes formation of several additional peroxyl radicals. Helicobacter pylori mutant strains with disruptions in genes encoding the peroxiredoxins, alkyl hydroperoxide reductase (ahpC) and the bacterioferritin comigratory protein (bcp), were more sensitive than the parent strain to oxidizing agents. These mutant strains were particularly sensitive, compared to the wild type, to killing by the unsaturated fatty acid linolenic acid but were not sensitive to the saturated fatty acid
palmitic acid
. A double mutant strain (ahpC bcp) accumulated more than 3-fold more lipid peroxides than the parent strain, indicating these peroxiredoxins together play a role in detoxifying lipid peroxides. The level of free iron accumulation, a signature of oxidative stress damage, was correlated specifically to organic peroxide-mediated stress by both in vivo and in vitro approaches. Free iron accumulation and concomitant destruction of [Fe-S] cluster-containing proteins (
hydrogenase
and aconitase) was correlated to damage mediated by exogenous t-butyl peroxide, or separately to intracellular accumulation of lipid peroxides in mutant strains. A major macromolecular target of accumulating lipid peroxides in H. pylori is DNA, as mutant analysis approaches combined with quantitative DNA fragmentation studies and specific DNA damage assessment (i.e. 8-oxoguanine formation) were used to demonstrate that such damage was especially associated with ahpC and ahpC bcp strains.
...
PMID:Lipid peroxidation as a source of oxidative damage in Helicobacter pylori: protective roles of peroxiredoxins. 1706 77
Visible light-driven redox reactions have been widely adopted for the production of chemicals to combat energy shortage and global warming. Key elements of such a reaction system include a photosensitizer, a catalyst, and an electron source. In this review, we introduce the small molecules and nanoparticles that are widely used as photosensitizers, as well as the development of a photosensitizer protein that is based on the expansion of genetic code, with a fluorescent protein that is used as a scaffold. Visible light-driven enzymes using proteins as photosensitizers or as catalysts such as carbon monoxide dehydrogenase (CODH), formic acid dehydrogenase (FDH),
hydrogenase
, nitrogenase, cytochrome P450 BM3, and alkane synthase are then described. CODH can be coupled with photosensitizing nanoparticles to reduce CO
2
to CO, and
hydrogenase
can produce H
2
using high-energy electrons produced from dye-sensitized nanoparticles. When water-soluble zinc porphyrin is coupled with FDH, visible light drives CO
2
to produce formic acid. Nitrogenase can reduce N
2
to NH
3
using CdS nanoparticle as photosensitizer. Cytochrome P450 BM3 can be enhanced by a visible light-driven redox system and thus by hydroxylate lauric acid or fatty acids. CvFAP, an alkane synthase, can decarboxylate
palmitic acid
to pentadecane under blue light excitation. Moreover, we describe a genetically encoded photosensitive protein, which mimics the function of natural photosynthesis and catalyzes the conversion of CO
2
to CO when covalently attached with a Ni-terpyridine complex.
...
PMID:Coupling natural systems with synthetic chemistry for light-driven enzymatic biocatalysis. 3131 82
