We have prepared single (N204D) and double (N204D:L272A) mutants of human uracil DNA glycosylase (hUDG), generating two cytosine DNA glycosylases (hCDG and hCYDG). Both these enzymes are able to excise cytosine (but not 5-methylcytosine), when this base is part of a mismatched base pair. hCDG is more active than the equivalent E. coli enzyme (eCYDG) and also has some activity when the cytosine ...

The partial 16S rRNA sequence of an unknown bacterium that was originally isolated from middle ear fluids of children with persistent otitis media was determined by reverse transcription. A comparison of this sequence with sequences from other gram-positive species having low guanine-plus-cytosine contents revealed that this bacterium represents a new line of descent, for which the name Alloioc...

Calculations are carried out to determine elastic-scattering cross sections and resonance energies for low-energy electron impact on uracil and on each of the DNA bases (thymine, cytosine, adenine, and guanine), for isolated molecules in their equilibrium geometry. Our calculations are compared with the available theory and experiment. We also attempt to correlate this information with experime...

A new group of Cytophaga-like bacteria has been recovered from healthy and diseased turbot in Scotland. Cultures produced orange colonies and contained short rods with distinctively thick cell walls. Gliding movement was observed and the guanine plus cytosine ratio of the DNA was 31.7 to 32.1 mols %. The organism caused gill hyperplasia and systemic haemorrhagic septicaemia in both naturally di...

Guanidine-based peptide nucleic acid (GPNA) monomers and oligomers containing all four natural (adenine (A), cytosine (C), guanine (G), and thymine (T)) and two unnatural (2-thiouracil (sU) and 2,6-diaminopurine (D)) nucleobases have been synthesized. Thermal denaturation study showed that GPNA oligomers containing alternate D-backbone configuration bind sequence-specifically to DNA and, when i...

Hyphomicrobium bacteriophage Hyphi30 and its nucleic acid were studied to determine some of their biochemical and biophysical properties. The molecular weight of the phage is 55.4 x 10(6), and its buoyant density is 1.508 g/ml. The nucleic acid of Hyphi30 is linear, double-stranded DNA with a molecular weight of 29.7 x 10(6). The guanine-plus-cytosine content of the DNA was 62% as determined fr...

Actinomycetes are comprised of diverse group of organisms that are Gram positive with guanine plus cytosine content in their DNA being greater than 55M % [1]. The term actinomycetes is coined from two greek words, atkis meaning ray and mykesmeaning fungus [2]. This is because the organisms have both fungi and bacteria like features. Like fungi, they form mycelia network branching filaments whil...

Using cyanoethyldiisopropylamino phosphoramidite chemistry, four oligonucleotides constituting a part of the sequence of the initiator t-RNA from B. subtilis were synthesized. For the protection of the exocyclic amino functions of bases, phenoxyacetyl group was used for adenine and guanine, and acetyl group was preferred for cytosine. With these labile groups, final deprotection of the oligonuc...

A heat stable cell growth inhibiting factor was isolated from rat liver microsomes by hot salt extraction, ethanol fractionation and the hot phenol method. The factor was contained in the RNA fraction (designated as mhRNA). mhRNA inhibited the growth of mouse fibroblast (L-929) cells at a relatively low concentration (55 microgram/ml of culture medium). The molecular weight of mhRNA was about 2...