Disease relevance of Hydroxyl radical

• M1 RNA (the catalytic subunit) alone and the RNAase P holoenzyme from E. coli cleave the tRNA-like structure of TYMV RNA in vitro at the 5' side of the quasi-helical structure to generate 5' phosphate and 3' hydroxyl groups in the cleavage products [1].
• We show that virions and purified viral cores contain a unique endonuclease that cleaves RNAs containing a 5' methylated cap structure (m7GpppXm) preferentially at purine residues 10 to 14 nucleotides from the cap, generating fragments with 3'-terminal hydroxyl groups [2].
• In the crystal structure of the tyrosyl tRNA synthetase (of Bacillus stearothermophilus), the side-chain hydroxyl of Thr 51 appears to make a weak hydrogen bond with the AMP moiety of the substrate intermediate, tyrosyl adenylate [3].
• A major portion of the toxicity of hydrogen peroxide in Escherichia coli is attributed to DNA damage mediated by a Fenton reaction that generates active forms of hydroxyl radicals from hydrogen peroxide, DNA-bound iron, and a constant source of reducing equivalents [4].
• The DNA polymerase from phage phi29 is a B family polymerase that initiates replication using a protein as a primer, attaching the first nucleotide of the phage genome to the hydroxyl of a specific serine of the priming protein [5].

Psychiatry related information on Hydroxyl radical

• Sodium hydroxide decontamination of Creutzfeldt-Jakob disease virus [6].
• PURPOSE: Using established prostate carcinoma cell lines, we studied the effect of androgens on various parameters of oxidative state (e.g., generation of hydrogen peroxide and hydroxyl radicals, lipid peroxidation, and oxygen consumption) and antioxidant defense mechanisms (e.g., the glutathione system and catalase) [7].
• These results suggest that at least one mechanism of rifampicin-mediated inhibition of A beta aggregation and neurotoxicity involves scavenging of free radicals and that rifampicin and/or appropriate hydroxyl radical scavengers may have therapeutic potential for Alzheimer's disease [8].
• Computer modeling of the Id reveals a conformational structure largely dependent on hydroxyl groups in or near turn position 4 of the H chain CDR3 region [9].
• Among the various causes of gastric ulceration, lesions caused by stress, alcohol consumption, Helicobacter pylori and due to use of non-steroidal anti-inflammatory drugs have been shown to be mediated largely through the generation of reactive oxygen species, especially the hydroxyl radical [10].

High impact information on Hydroxyl radical

• This suggests a model of the RAG protein active site in which two divalent metal ions serve alternating and opposite roles as activators of attacking hydroxyl groups and stabilizers of oxyanion leaving groups [11].
• The metal-activated hydroxide ion is a critical nucleophile in metalloenzymes that catalyze hydrolysis or hydration reactions [12].
• Orientation of ribosome recycling factor in the ribosome from directed hydroxyl radical probing [13].
• During TPRT, the LINE-1 endonuclease cleaves genomic DNA, freeing a 3' hydroxyl that serves as a primer for reverse transcription of LINE-1 RNA by LINE-1 reverse transcriptase [14].
• The observed nonhomologous recombinations are entirely dependent on the 3' hydroxyl group of the 5' fragment, and are due to a splicing-like reaction in which RNA secondary structure guides the attack of this 3' hydroxyl on phosphoester bonds within the 3' fragment [15].

Chemical compound and disease context of Hydroxyl radical

• Directed hydroxyl radical probing of 16S and 23S rRNA from Fe(II) tethered to ten positions on the surface of E. coli RRF constrains it to a well-defined location in the subunit interface cavity [13].
• Hydrogen peroxide-mediated toxicity for Leishmania donovani chagasi promastigotes. Role of hydroxyl radical and protection by heat shock [16].
• Inasmuch as 5-aminosalicylic acid (the therapeutic moiety of sulfasalazine) has been reported to be a hydroxyl radical scavenger, we also assessed the effects of dimethylsulfoxide (another hydroxyl radical scavenger) on ischemia/reperfusion-induced gastric mucosal injury [17].
• When salicylate trapping of hydroxyl radicals and measurement of levels of malondialdehyde were used, there was no evidence throughout disease progression in mice for enhanced production of hydroxyl radicals or lipid peroxidation, respectively [18].
• There was the expected increase in O2-. production during hypoxia/reoxygenation that cytochrome P-450 inhibitors did not prevent; on the other hand, inhibitors did prevent reoxygenation-induced hydroxyl radical formation [19].

Biological context of Hydroxyl radical

• TFIID binding in the minor groove of DNA at the TATA element was demonstrated by methylation interference and hydroxyl radical footprinting assays, and by binding studies with thymine analog substituted oligonucleotides [20].
• Moreover, elimination of a single transmembrane hydroxyl group severely inhibits antigen presentation without affecting signal transduction, suggesting that these two functions are mediated by different protein interactions [21].
• We have used oligodeoxynucleotide-directed mutagenesis to construct two point mutants at this site: one to remove the hydroxyl group (Thr 51 leads to Ala 51) and the other, in addition, to distort the local polypeptide backbone (Thr 51 leads to Pro 51) [3].
• Current estimates of CH3Br and CH3Cl emissions from oceanic sources, terrestrial plants and fungi, biomass burning and anthropogenic inputs do not balance their losses owing to oxidation by hydroxyl radicals, oceanic degradation, and consumption in soils, suggesting that additional natural terrestrial sources may be important [22].
• For both spliceosomal and group II introns, the first-step reaction occurs by nucleophilic attack on the 5' splice junction by the 2' hydroxyl of an internal adenosine, forming a 2'-5' phosphodiester branch in the intron [23].

Anatomical context of Hydroxyl radical

• Hydroxyl radical formation in neutrophils [24].
• Mapping the position of translational elongation factor EF-G in the ribosome by directed hydroxyl radical probing [25].
• Hydroxyl radical scavengers inhibit human natural killer cell activity [26].
• These observations constitute chemical evidence for the generation of hydroxyl radicals by microsomes [27].
• Studies with rat hepatocytes and liver microsomes indicated that sulfation of the phenolic hydroxyl group facilitates the deiodination of these compounds [28].

Associations of Hydroxyl radical with other chemical compounds

• Here we describe mutagenesis, hydroxyl-radical footprinting and X-ray studies that elucidate the structure of a 1:1 cisplatin-modified DNA/HMG-domain complex [29].
• The excised intervening sequence retains the branch site and terminates in a guanosine residue with a 3' hydroxyl group [30].
• Both the iodinating and bactericidal activities were inhibited by catalase and the hydroxyl radical (OH.) scavenger mannitol, whereas superoxide dismutase was ineffective [31].
• That the determinant responsible for this stimulation was DNP coupled to the hydroxyl group of tyrosine was shown by selective removal of DNP from tyrosine by thiolysis with 2-mercaptoethanol, which abolished their ability to stimulate T cells [32].
• Hydrogen peroxide and superoxide, two agents known to occur during phagocytosis, are thought to interact to generate hydroxyl radical, singlet oxygen, and other potentially reactive molecules [33].
• Using duplex oligodeoxynucleotides containing all possible three-nucleotide sequence contexts for guanine, the method was used to assess the role of DNA sequence context in hydroxyl radical-induced guanine oxidation associated with gamma-radiation and Fe2+-EDTA/H2O2 [34].

Gene context of Hydroxyl radical

• The reduction of copper(II) to copper(I) by APP involves an electron-transfer reaction and could enhance the production of hydroxyl radicals, which could then attack nearby sites [35].
• The hydroxyl radical (OH.) scavenger dimethyl sulfoxide (DMSO) was found to dose-dependently inhibit interleukin 8 (IL-8) production in LPS-stimulated human whole blood [36].
• C4B reacts much more effectively with hydroxyl groups than C4A and this is reversed for reaction with amino groups in spite of the very small difference in amino acid sequence between the two forms of C4 [37].
• A quantification of the hydroxyl radical footprints allowed us to compare further the affinity of the LexA repressor for the recA operator with that of its isolated DNA binding domain [38].
• When probed with hydroxyl radicals, ssDNA-RAD52 complexes exhibit a four-nucleotide repeat hypersensitivity pattern [39].

Analytical, diagnostic and therapeutic context of Hydroxyl radical

• Here we examine the structure of this complex using gel mobility-shift assays and hydroxyl-radical footprinting [40].
• DNA footprinting with hydroxyl radical [41].
• Mononuclear phagocytes have the potential for sustained hydroxyl radical production. Use of spin-trapping techniques to investigate mononuclear phagocyte free radical production [42].
• Hydroxyl radical-mediated protein footprinting using mass spectrometry has recently been developed to define structure, assembly, and conformational changes of macromolecules in solution based on measurements of reactivity of amino acid side chain groups with covalent modification reagents [43].
• This suggested the presence of labile sulfated cholenoic acids with an allylic hydroxyl group, a conclusion supported by analysis using fast atom bombardment mass spectrometry (FAB-MS) [44].

References