PubMed Health⌕ Search

Biomedical subjects

J Turna

Publications and source records attributed to J Turna.

27 records · Page 2Linked to original sources
PubMed1993

Cloning of toxic genes with mini-mu derivative of bacteriophage mu.

We describe an in vivo cloning method using mini-Mu phage for genes, which cannot be cloned on multicopy vectors, mainly for their toxicity. We have successfully cloned succinate dehydrogenase (sdh) gene E. coli which was inactivated with defined insertion of fragment Kmr by this method. The most of obtained Kmr clones of mini-Mu transductants have contained the sequence of whole sdh gene. The intact gene of sdh can be reconstructed by site-directed mutagenesis.

Bacteriophage mu↗
PubMed1992

Isolation of a new restriction enzyme, ApaCI, an isoschizomer of BamHI produced by Acetobacter pasteurianus.

A new Type II restriction endonuclease ApaCI purified from Acetobacter pasteurianus is an isoschizomer of BamHI that cleaves at the nucleotide sequence 5'-G/GATCC-3' of double-stranded DNA. The single restriction activity present in this strain permits rapidly purified 30,000 units of cleavage activity from 10 g of freshly harvested cells. The resulting ApaCI preparation is free of contaminant nuclease activities that might interfere with in vitro manipulation of DNA.

Acetobacter↗
PubMed1992

Construction of shuttle vectors for cloning in Escherichia coli and Acetobacter pasteurianus.

New cloning vectors were prepared with the aid of a large plasmid isolated from Acetobacter pasteurianus and from plasmids pBR322 and pUC4-KAPA. Of the prepared cloning vectors, pACK5 contains a gene coding for kanamycin resistance, pACT7 and pACT71 contain a gene coding for tetracycline resistance and vector pACG3 with a gene coding for both kanamycin and tetracycline resistance. The vectors prepared only contained the beginning of replication from the pAC1 plasmid and possessed the ability to replicate within E. coli and A. pasteurianus. The vectors are highly stable in both strains and during the 5-d cultivation under nonselective conditions are not eliminated.

Acetobacter↗
PubMed1992

Expression of chimeric proteins encoded by the fused BLV reverse transcriptase: beta-galactosidase in Escherichia coli.

The gene for bovine leukemia virus (BLV) reverse transcriptase was cloned in prokaryotic expression vector pUC8-2. After fusion of Escherichia coli lacZ gene to different parts of reverse transcriptase we detected expression of new proteins with molecular weights corresponding to the size of the hybrid genes. A coding region most probably responsible for about a hundred-fold decrease in expression of long fusion proteins has been identified. A few possible causes of this phenomenon were tested.

Escherichia coli↗
PubMed1989

[Use of recombinant DNA technics in the diagnosis of hereditary diseases].

Recombinant DNA techniques, referred to as genetic engineering or gene manipulation, are used to advantage in medicine for the preparation of hormones, vaccines, immunomodulators, and diagnostic preparations. They enable to introduce new, highly effective diagnostic tools particularly for the identification of defects in the human genome at molecular level. They present methods of direct analysis of genetic material, even without preceding knowledge on the biochemical mechanism of the disease. The aim of the presented paper was to elucidate the substance of direct gene analysis and of indirect analysis by means of genetic linkage, the use of DNA probes and the phenomenon of restriction of fragment length polymorphism (RFLP). The paper gives a concise view on the present state of the problem worldwide as well as on the situation in the Slovak Socialist Republic. (Tab. 1, Fig. 7, Ref. 24.)

DNA Probes↗
PubMed1988

Purification of murine alpha-herpesvirus and some properties of its DNA.

Strain Sumava Af of murine alpha-herpesvirus (MHV) banded in density gradient at the boundary between 10-20% and 20-30% Ficoll solution. In electron microscope, the partially purified virus visualized by negative staining exhibited intact or disrupted envelope structures and capsid particles of about 110 nm in outer diameter. The DNA extracted from partially purified virus and further purified in CsCl density gradient had the Tm-value of 79.0 degrees C. The molecular weight of about 90 million daltons was calculated for viral DNA according to its migration in agarose gel.

Base Composition↗
PubMed1983

Preparation of highly purified mitochondria of Neurospora crassa on a Percoll gradient.

Mitochondria isolated from Neurospora crassa were purified by centrifugation in a Percoll density gradient. Enzyme activities and cytochrome differential spectra revealed a high purity of the mitochondria. As compared with a crude mitochondrial fraction the purified mitochondria exhibited a high respiratory activity and a fine ADP/O ratio. Electrophoresis of nucleic acids demonstrated the absence of cytoplasmic rRNA.

Adenosine Diphosphate↗