We have recently isolated a herpes simplex virus (HSV) type 2 (strain 333)-specific cDNA that encodes uracil-DNA glycosylase. This cDNA lies between 0.065 and 0.08 map units on the HSV genome. Within this region there are five overlapping transcripts which encompass three open reading frames. We have determined that the second open reading frame, UL-2, codes for glycosylase. In vitro transcript...

Growth of a strain of Bacillus subtilis that requires uracil, thymine, adenine, and tryptophan in the presence of 5-fluorouracil (FU) results in the synthesis of ribonucleic acid (RNA) and ribosomes in which 55 to 65% of the RNA uracil has been replaced by the fluorine derivative. Examination of analogue-containing ribosomes by sucrose density gradient centrifugation and thermal denaturation st...

background: saccharomyces boulardii (s. boulardii) is the best known probiotic yeast. the genetic engineering of this probiotic strain requires the availability of appropriate mutants to accept various gene constructs carrying different selection markers. as the auxotrophy selection markers are under focus, we have generated a ura3 auxotroph mutant of s. boulardii for use in further genetic man...

The present work includes synthesis of new series heterocyclic derivatives containing 6-amino-1,3-dimethyl uracil moiety linked to 1,2,4-triazole [6-8 and 10]. first way reaction 6-amino-1,3-dimethyluracil with ethyl chloroacetate K2CO3 as catalyst in DMF solvent gives ester derivative [1]. Then, compound [1] was converted into (semicarbazide, thiosemicarbazide, phenylsemicarbazide hydrazide de...

Recent investigations have shown that the animal microorganism, Tetrahymena geleii, requires an exogenous source of pyrimidine for growth (1). This requirement can be met by the addition of cytidylic acid or uracil to the medium (2). Cytosine and thymine are without activity. The failure to utilize the latter two free bases was interpreted as indicating a block in the ability of the organism to...

The role of the conserved histidine-187 located in the leucine intercalation loop of Escherichia coli uracil-DNA glycosylase (Ung) was investigated. Using site-directed mutagenesis, an Ung H187D mutant protein was created, overproduced, purified to apparent homogeneity, and characterized in comparison to wild-type Ung. The properties of Ung H187D differed from Ung with respect to specific activ...

A strain of Klebsiella aerogenes is described which was unable to grow from light inocula on 5% lysed horse blood diagnostic sensitivity test (DST) agar. It was able to grow on DST agar without added horse cells and MacConkey and nutrient agar. Growth on a deficient medium was promoted by sulphonamides and nitrofurantoin as well as by para-amino benzoic acid, para-amino salicylic acid, procaine...

Neq DNA polymerase is the first archaeal family B DNA polymerase reported to lack uracil recognition function and successfully utilize deaminated bases. We have focused on two amino acid residues (Y515, A523) in the fingers subdomain of Neq DNA polymerase, which were predicted to be located in the middle of the fingers subdomain, based on amino acid sequence alignment of the Neq DNA polymerase ...

Uracil-DNA glycosylase releases free uracil from DNA and initiates base excision repair for removal of this potentially mutagenic DNA lesion. Using the yeast two-hybrid system, human uracil-DNA glycosylase encoded by the UNG gene (UNG) was found to interact with the C-terminal part of the 34-kDa subunit of replication protein A (RPA2). No interaction with RPA4 (a homolog of RPA2), RPA1, or RPA3...