The methylated bases of DNA are formed by the transfer of the methyl group from S-adenosylmethionine to a polynucleotide acceptor. This transfer is catalyzed by highly specific enzymes which recognize a limited number of available sites in the DNA. The mechanism for the recognition is presently unknown. In some instances, there is evidence that other cellular components, such as lipopolysaccharides, can influence the methylation reaction. Certain bacteriophages induce new methylases upon infection of their hosts. Phage T3 is unique in establishing an environment in which methylation of neither the phage nor the host nucleic acid can occur. By superinfecting T3-infected cells with other phages, the latter can be obtained with methyl-deficient DNA. Although a great deal is known about the enzymology of the methylation reaction, and there appears to be a strong correlation between the in vitro and in vivo reactions, studies in which DNA is either supermethylated or totally unmethylated have not yielded any insight as to what the possible function of the methylated bases may be.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2195544 | PMC |
http://dx.doi.org/10.1085/jgp.49.6.5 | DOI Listing |
J Inorg Biochem
December 2024
Department of Molecular and Analytical Chemistry, Interdisciplinary Excellence Centre, University of Szeged, Dóm tér 7-8, H-6720 Szeged, Hungary. Electronic address:
Schiff bases derived from aminoguanidine are extensively investigated for their structural versatility. The tridentate 2-formylpyridine guanylhydrazones act as analogues of 2-formyl or 2-acetylpyridine thiosemicarbazones, where the thioamide unit is replaced by the guanidyl group. Six derivatives of 2-formylpyridine guanylhydrazone were synthesized and their proton dissociation and complex formation processes with Cu(II), Fe(II) and Fe(III) ions were studied using pH-potentiometry, UV-visible, NMR and electron paramagnetic resonance spectroscopic methods.
View Article and Find Full Text PDFElife
December 2024
Plant Evolutionary Ecology, Institute of Evolution and Ecology, University of Tübingen, Tübingen, Germany.
Understanding the genomic basis of natural variation in plant pest resistance is an important goal in plant science, but it usually requires large and labor-intensive phenotyping experiments. Here, we explored the possibility that non-target reads from plant DNA sequencing can serve as phenotyping proxies for addressing such questions. We used data from a whole-genome and -epigenome sequencing study of 207 natural lines of field pennycress () that were grown in a common environment and spontaneously colonized by aphids, mildew, and other microbes.
View Article and Find Full Text PDFDalton Trans
December 2024
Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt, Main, Germany.
Aluminum-doped polycyclic aromatic hydrocarbons (PAHs) are underexplored despite the broad applications of boron-containing PAHs in areas such as catalysis and optoelectronics. We disclose the donor-free, sterically unprotected 9-methyl-9-aluminafluorene (Me-AlFlu; 2), synthesized by heating a 9,9-dimethyl-9-stannafluorene and AlMe in hexanes. The compound is a dimer, (2), with -positioned Al substituents in the solid state.
View Article and Find Full Text PDFUrolithiasis
December 2024
Department of Urology, The Second Affiliated Hospital of Xi'an Jiaotong University, No. 157, Xiwu Rd., Xi'an, 710004, Shaanxi Province, China.
Urolithiasis, a common urological disorder affecting about 10% of the global population, is known for its high recurrence rate, yet its genetic mechanisms remain poorly understood. This study aimed to fill this gap by identifying potential pathogenic genes associated with urolithiasis using a multi-omics Mendelian randomization approach. We conducted a comprehensive analysis that integrated genome-wide association studies (GWAS), expression quantitative trait loci (eQTL), methylation quantitative trait loci (mQTL), and protein quantitative trait loci (pQTL) data.
View Article and Find Full Text PDFJ Inherit Metab Dis
January 2025
Centre for Biomedical Network Research on Rare Diseases (CIBERER), Madrid, Spain.
Maple syrup urine disease (MSUD) is a rare inherited metabolic disorder characterized by deficient activity of the branched-chain alpha-ketoacid dehydrogenase (BCKDH) complex, required to metabolize the amino acids leucine, isoleucine, and valine. Despite its profound metabolic implications, the molecular alterations underlying this metabolic impairment had not yet been completely elucidated. We performed a comprehensive multi-omics integration analysis, including genomic, epigenomic, and transcriptomic data from fibroblasts derived from a cohort of MSUD patients and unaffected controls to genetically characterize an MSUD case and to unravel the MSUD pathophysiology.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!