Robert E. Enns

Learn More
A 5.7-kb recombinant plasmid, called XD-7, contains the terminal XbaI-E fragment from the left end of type 2 adenovirus cloned into the EcoRI site of pBR322. An average of 9% +/- 1% of input supercoiled, protein-free XD-7 DNA replicated as rolling circles with single-stranded tails ranging up to unit length and longer in reaction mixtures containing nuclear(More)
In vivo and in vitro evidence is presented implicating a function of GATC methylation in the Escherichia coli replication origin, oriC, during initiation of DNA synthesis. Transformation frequencies of oriC plasmids into E. coli dam mutants, deficient in the GATC-specific DNA methylase, are greatly reduced compared with parental dam+ cells, particularly for(More)
Cross-resistance between cisplatin (DDP) and metalloid salts in human cells was sought on the basis that mechanisms that mediate metalloid salt cross-resistance in prokaryotes are evolutionarily conserved. Two ovarian and two head and neck carcinoma cell lines selected for DDP resistance were found to be cross-resistant to antimony potassium tartrate, which(More)
The metal compound cisplatin (DDP) is a widely used anticancer agent but naturally occurring and acquired resistance to DDP limits its effectiveness. Resistance is associated with a decreased accumulation of DDP and increased levels of glutathione and metallothioneins. Such changes also serve as protective and detoxification mechanisms for other metal salts(More)
Arsenite resistance in bacteria is mediated by an efflux pump composed of the arsA and arsB gene products. We have isolated the human homolog of the bacterial arsA (hARSA-I), a member of the ATPase superfamily with no transmembrane domain. Southern and Northern analyses indicated the presence of two cross-hybridizing genes in the human genome and expression(More)
The expression of the 60-kDa heat-shock protein (HSP60) varies markedly among patients with ovarian carcinoma, and high-level expression predicts poor survival in such patients treated with cisplatin (DDP)-containing chemotherapy programs. We investigated the expression of HSP60 in human ovarian carcinoma 2008 cells and an 11-fold DDP-resistant subline(More)
PURPOSE Ovarian carcinomas express the 60-kD heat-shock protein HSP-60 at widely varying levels in different tumors. The aim of this study was to determine whether there was a relationship between expression of HSP-60 and survival in patients with ovarian carcinoma. MATERIALS AND METHODS Total RNA and DNA were prepared from 51 epithelial ovarian cancer(More)
Mutants of Schizosaccharomyces pombe were used to define genes involved in the cell cycle arrest produced by cisplatin (DDP), an agent that causes both DNA damage and inhibition of DNA synthesis. Previous work has demonstrated that strains with defective or absent wee1+ function fail to arrest in G2 when DNA is damaged, but do arrest when DNA synthesis is(More)
We have developed a standardized, quantitative assay to study the function of a cloned adenovirus origin. We have shown that the adenovirus origin is located within the first 20 bp of the adenovirus inverted terminal repetition (ITR), a region containing a sequence conserved among human, simian, murine, and avian adenoviruses. Deletions removing or(More)
M13 cloning vehicles have been constructed which contain the Escherichia coli origin for DNA replication (oriC), with and without selectable antibiotic-resistance genes. Since the M13 viral strand origin requires a functional rep gene product, using oriC these vehicles propagate as low-copy-number plasmids in E. coli rep mutants. This property is exploited(More)
  • 1