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M Mordarski

Publications and source records attributed to M Mordarski.

At least 37 records · Page 2Linked to original sources
PubMed1992

Identification of Staphylococcus epidermidis using a 16S rRNA-directed oligonucleotide probe.

Staphylococcus epidermidis is the most medically significant of the coagulase-negative staphylococci. An oligonucleotide probe (pSe) for identification of S. epidermidis was defined by comparing the sequences of the 16S rRNA variable region V6 from numerous coagulase-negative staphylococci. In order to increase the sensitivity of the detection, polymerase chain reaction amplification of the variable region with primers based on the conserved flanking sequences was applied. The detection limit of the polymerase chain reaction assay combined with pSe probe was shown to be 1 fg which corresponds to about one single bacterium. Additionally, a sensitive, non-radioisotopic system with chemiluminescence detection was tested.

Base Sequence↗
PubMed1992

A carboline derivative as a novel mammalian DNA topoisomerase II targeting agent.

The DNA intercalating, ellipticine analog drug, 5,11-dimethyl-5H-indol[2,3-b]quinoline, is able to stabilize in vitro the topoisomerase II-DNA cleavable complex and to induce DNA breaks in BPV I episome in rat fibroblasts. Cytotoxicity studies with DC3F cells resistant to ellipticine strongly suggest that topoisomerase II is a cellular target involved in the mechanism of cytotoxic action of this carboline derivative.

Amsacrine↗
PubMed1991

Polyphasic taxonomic study of the genera Gordona and Tsukamurella including the description of Tsukamurella wratislaviensis sp. nov.

Representatives of the genera Gordona and Tsukamurella together with related actinomycetes were the subject of chemotaxonomic, numerical taxonomic and DNA homology studies. In the numerical analysis the organisms were examined for 116 unit characters and the data sorted using the simple matching, Jaccard and pattern coefficients; clustering was achieved using the unweighted pair group method with arithmetic averages algorithm. The numerical groupings were not affected by the statistics used or by test error, estimated at 1.9%. The numerical taxonomic data supported the integrity of the four validly described species of Gordona but indicated that the genus Tsukamurella might encompass a species in addition to Tsukamurella paurometabola. The putative new strains had chemical, enzymic, nutritional and tolerance properties consistent with their assignment to the genus Tsukamurella and formed a DNA homology group corresponding to the one formed by the Tsukamurella paurometabola strains. It is proposed that the new taxon be assigned to the genus Tsukamurella as Tsukamurella wratislaviensis.

Actinomycetales↗
PubMed1991

DNA restriction endonuclease analysis of some Streptomyces species.

Relationship between some Streptomyces species were determined by restriction endonuclease analysis (REA). DNA isolated from twelve representative Streptomyces strains was analysed using Sal I endonuclease. The results indicate that REA patterns can be used to determine variation both between as well as within species of Streptomyces.

DNA Restriction Enzymes↗
PubMed1991

[Ribosomal RNA-specific DNA probes used in microbiology].

Recent advances in molecular biology and gene technology made it possible to identify microorganisms on the basis of most stable characters directly linked to the molecular structure of the genome. One of the most basic technics in this field is reassociation between two complementary strands of nucleic acids (DNA and RNA) isolates from different microorganisms. A probe is a specific fragment of single stranded nucleic acid (DNA or RNA) that binds to the complementary, target nucleic acid. Several aspects of probes designation and diagnostic application are presented and discussed.

Bacteria↗
PubMed1989

Bacterial colony screening with a Streptomyces DNA probe.

Restriction fragments of 1.5 kb-3.5 kb length were selected from a SalI digest of Streptomyces coriofaciens ISP5485 DNA. After radiolabelling, these fragments were used as a molecular probe. A number of actinomycetes was screened in colony hybridization. Streptomyces and Streptoverticillium strains were recognized by the probe and the hybridization sensitivity was high with isolated DNA.

Actinomycetales↗
PubMed1988

Deoxyribonucleic acid relatedness amongst Staphylococcus epidermidis and Staphylococcus saprophyticus strains.

The degree of binding was determined between DNA preparations from 65 staphylococci representing cluster defined in a numerical phenetic survey and 3H-labelled DNA from reference strains of S. epidermidis, S. haemolyticus, S. hominis, S. saprophyticus and S. warneri. The congruence between the DNA pairing and numerical phenetic data was good with S. epidermidis and S. saprophyticus being shown to be genomic species. However, some strains identified as S. epidermidis using recommended diagnostic procedures were found to belong to other taxa, notably S. simulans and S. warneri. The moles percent guanine plus cytosine content of the DNA of the test strains was within the range 27 to 34.

Base Composition↗
PubMed1988

New inhibitors for aminoglycoside-adenylyltransferase.

Two hydroxymethyltropolones and two tropolone acetate derivatives were found to inhibit an aminoglycoside-adenylyltranferase in a gentamicin-resistant Escherichia coli strain. The inhibitory effect of tropolones depends on the nature of the aminoglycoside antibiotic subject to adenylation. Combinations of hydroxymethyltropolones with tobramycin were more active compared with tropolone acetates against gentamicin-resistant strains displaying adenylyltransferase activity. On the contrary a combination of the investigated acetate with gentamicin was of lower activity. It could be shown that these inhibitors inhibit, to a varying degree, the transfer of radioactive ATP to different aminoglycoside molecules.

Cycloheptanes↗
PubMed1988

Antibacterial activity of selected tropones and tropolones.

The antibacterial activity of 33 substituted and unsubstituted seven-member ring tropones and tropolones was examined on 14 reference strains representing Gram-positive and Gram-negative bacteria. It was shown that the chemical character and position of the substituent plays a distinct role in the biological activity of investigated compounds. Depending on the substituent the antibacterial effect may be either increased or diminished. C-1 thio and C-2 nitro derivatives of tropone are significantly more active than tropone. The dibenzotropone derivatives display no antibacterial activity. Hydroxymethyl derivatives of tropolone are more active than tropolone, while hydroxy-, isopropyl-, methyl- as well as tropolone acetates are equipotent.

Anti-Bacterial Agents↗
PubMed1988

DNA base composition and homology values in the classification of some Rhodococcus species.

Similar DNA homology values were recorded when a modified S1 nuclease technique and a standard nitrocellulose membrane filter method were applied to representative strains of Rhodococcus. The DNA homology data showed that R. globerulus, R. luteus and R. sputi form distinct genomic species. The congruence between the DNA homology and earlier numerical phenetic data was good, but there was evidence that some strains had been misclassified in the previous studies. In particular, the type strains of R. obuensis and R. sputi belong to a single genomic species. The former name is thus a later, subjective synonym of the latter. The guanine plus cytosine content of the DNA of the rhodococci fell within the range 61 to 72 mol%.

Base Composition↗
PubMed1987

Microbial transformation of azacarbazoles. IV. Conversion of chloro-substituted alpha-carbolines by Kitasatosporia setae strain.

Biotransformation of alpha-carboline derivatives substituted at positions C-5, C-6, C-7 and C-8 with chlorine, carried out with Kitasatosporia setae strain yielded corresponding 1-methyl-alpha-iso-carbolines. The formation of products is dependent on the position of chlorine in substrate molecule. When chlorine is introduced at C-6, the yield of N-1 methylation is low, about 5%. Derivatives of alpha-carboline substituted with chlorine at C-7 and C-8 form corresponding alpha-iso-carbolines with yield up to 20% and 30%, respectively, whereas 5-chloro-alpha-carboline is converted into 5-chloro-1-methyl-alpha-iso-carboline with 60% yield. Apparently, additional pathway of microbial transformation of 2-chloro-alpha-carboline has been found. Primarily formed 2-chloro-1-methyl-alpha-iso-carboline subjected to complex enzymic conversion yields quantitatively 2-methoxy-1-methyl-alpha-iso-carboline-9-N-oxide. It has been found that 2-chloro-1-methyl-alpha-iso-carboline exhibit strong cytotoxic activity, against KB cells tissue culture, ID50 = 0.01 microM/ml and inhibits growth of Kitasatosporia setae strain, MIC = 0.5 microM/ml. Toxicity of formed 2-methoxy-1-methyl-alpha-iso-carboline-N-9-oxide is markedly lower, ID50 = 0.3 microM/ml and MIC = 3.5 microM/ml. The remaining C-5, C-6, C-7 and C-8 chloroderivatives of alpha-iso-carboline occur to be less active than 2-chloro-1-methyl-alpha-iso-carboline.

Actinomycetales↗
PubMed1987

Microbial transformation of azacarbazoles. IX. Preliminary studies on hydroxylation of 2,3-benzo-1,4-dimethyl-alpha-iso-carboline by Paecilomyces flavinosus.

Microbial transformation of 2,3-benzo-1,4-dimethyl-alpha-iso-carboline performed with several strains of fungi Beauveria bassiana, Verticillum lecani and Paecilomyces flavinosus yielded common products which were expected to be hydroxylated derivatives of starting compound. Among the microorganisms tested, strain Paecilomyces flavinosus P-5 was selected to perform quantitative bioconversion of 2,3-benzo-1,4-dimethyl-alpha-iso-carboline for preparative scale.

Biotransformation↗
PubMed1987

Antineoplastic activity of azacarbazoles. II. Effect of alpha-carboline and its derivatives on transplantable animal neoplasms.

The antineoplastic properties of alpha-carboline, alpha-carboline hydrochloride, alpha-carboline N-1 methyl iodide and c-6 substituted fluoro-, chloro, nitro- and phenyl-alpha-carboline were studied. None of the compounds proved to be active when tested against i.p. transplanted B16 melanoma or i.m. implanted Lewis lung carcinoma. In addition, alpha-carboline was assessed against i.p. inoculated plasmacytoma MP26 and colon carcinoma 26, and solid tumors of mammary carcinoma 16/C and Walker carcinosarcoma 256. Under conditions tested these neoplasms did not respond to alpha-carboline.

Animals↗
PubMed1987

Antineoplastic activity of new linear hydrazine derivatives.

A series of hydrazine derivatives was tested for antineoplastic activity. Cyanoacetic acid hydrazide (I), cyanoacetic acid methylhydrazide (II) and N-thioamido-N'-cyano-acethylhydrazine (VI) appeared to be the most active agents against sarcoma 180, Ehrlich carcinoma and Nemeth Kellner lymphoma. The maximum tumor weight inhibition ranged from 70 to 90%. N, N'-bis-cyano-acethylhydrazine (IV) and N-isonicotinoyl-hydrazine (VIII) showed significant antitumor activity in Ehrlich carcinoma and Nemeth Kellner lymphoma systems. None of hydrazine derivatives were active against L1210 leukemia. The most active agents, I, II and VI were further evaluated in leukemia P388, melanoma B16, Lewis lung carcinoma and mammary carcinoma 16/C, and the agent VI was additionally tested in plasmacytoma MP26, colon carcinoma 26 abd Walker carcinosarcoma 256 systems. However, there was no effect with any agent or dose tested against any neoplasm.

Animals↗
PubMed1987

Kitasatosporia setae, an interesting actinomycete strain isolated from Spitsbergen soil.

The phenotypic and genotypic properties as well as cell chemistry of an interesting actinomycete, which converted certain azacarbazoles into highly cytotoxic derivatives, were established. The strain was also compared with two similar Japanese actinomycetes of Kitasatosporia gen. nov. A great resemblance between the strains was observed. Apart from similar phenotypic properties they were characterized by contents of both L- and meso-DAP, glycine and galactose as the main cell wall components. They proved to have the same phospholipid, glycolipid and fatty acid patterns. The guanine-plus-cytosine contents of the deoxyribonucleic acids of the strains averaged 72.5 and there was a high degree of homology between the DNAs of the strains (approximately 80%). These data provide evidence that the Spitsbergen isolate and the Japanese actinomycetes belong to one genomic species.

Actinomycetales↗