Antimicrobial effects of new 1-(1,2,4-triazol-1-yl)-acetanilides

Fourteen synthetically prepared 1-(1,2,4-triazol-1-yl)acetanilides were tested for antimicrobial effect. None of the prepared derivatives influenced theB. subtilis, P. fluorescens nor the tested yeasts. Only the derivatives with substituents in positionspara orortho andpara were biologically effective. The widest antimicrobial spectrum was manifested by the pentachloro derivative, which was effective with G⁺ and G^? bacteria and with filamentous fungi.     

Structure-activity relationships of some 4-quinazolylthiosemicarbazides and their triazolo derivatives

Eigh 4-quinazolylthiosemicarbazides and nine of their structural analogues have been tested for antibacterial effects and for structure activity relationships. 9-Chloro-5-morpholino-1,2,4-triazolo[4,3-c]quinazoline-3-thione has demonstrated the hightest antibacterial effect (MIC of 1 mg/L forE. coli andP. mirabilis and <1 mg/L forS. aureus andB. subtilis). The most effective derivatives have the carbon aromatic ring substituted with chlorine and the pyrimidine ring with morpholine or with secondary amine group.     

Transformation of tobacco and birdsfoot trefoil by lupin leghemoglobin I cDNA clone

The full length cDNA clone of leghemoglobin I gene fromLupinus luteus was placed under dual promoter into the plant expression vector pCB1399 and the resulting vector (pCB1415) was transfered into theAgrobacterium strain LBA4404 (pAL4404). The binary system LBA4404 (pAL4404, pCB1415) was then used for transformation ofNicotiana plumbaginifolia andLotus corniculatus. In both species kanamycin-resistant plants have been selected and regenerated. The synthesis of LbI protein in transformed plants has not been shown.     

The effect of glucosinolates (mustard oil glycosides) and products of their enzymic degradation on the infectivity of turnip mosaic virus

The effect of glucosinolates sinigrin, progoitrin, epiprogroitrin, gluconapin, gluconapoleiferin, glucobrassicanapin, glucotropaeolin and gluconasturtiin without and with the glucosinolate-degrading enzyme (myrosinase, EC:3.2.3.1.), on the infectivity of turnip mosaic virus was studied. Little or no effect was observed when the intact glucosinolate (2.5 μmol cm⁻³) was added to the suspension of turnip mosaic virus (TuMV, isolate Ruzyně; 0.2 mg cm⁻³ in 0.01 M potassium phosphate buffer) at both pH 7 and pH 6. A significant decrease of virus infectivity was, however, observed when 0.25, 1.25 and 2.5 μmol cm⁻³ of the glucosinolate together with 0.31, 1.56 and 3.13 mg cm⁻³ of the myrosinase, respectively, was added to the virus suspension of both pH 7 and pH 6. The effect, which was greater at pH 6, was most intense with sinalbin and glucobrassicin substrates.     

Dinitrogen fixation (Acetylene reduction) and nitrogen accumulation in peas cultivated under the standard growth conditions

InPisum sativum cultivated under standard growth conditions the extent of N₂ fixation with time estimated by the acetylene reduction assay (PN₂F) and rates of the actual nitrogen accumulation of plant biomass (ANA) were calculated from six independent growth experiments. In the plants inoculated with indigenous soilRhizobium populations and cultivated on 0.63 mmol/L nitrate level the percentage PN₂F:ANA ratios ranged from 25.7 to 61.5%. In peas inoculated with the inoculant strain the PN₂F:ANA ratios were markedly higher, ranging from 59.8 to 65.1%. The plants cultivated on N-free nutrient solutions showed both PN₂F:ANA and C₂H₄N₂ ratios to be somewhat higher compared with the 0.63 mmol/L nitrate cultivated plants.     

Participation of complement in nasal polyposis

No changes in immunoglobulin (IgG, IgM and IgA) and complement components C3 and C4 levels could be observed in patients suffering from both recurrent and acute nasal polyposis. However, in both groups of patients a significant decrease of the alternative pathway of complement activation (up to 80%) was found. In addition, patients suffering from the acute disease showed even decreased classical complement pathway (up to 20%). Examination of complement activation pathways was shown to be advantageous for the follow-up of the course of this disease.     

Synergistic effect of antibiotics and pesticides on wood-damaging fungi

The synergistic effect of kasugamycin and thiolutin as biopesticides with some synthetic pesticides (benlate, euparen, dithan and pentachlorophenol) toward wood-damaging fungiCladosporium sphaerospermum, Ceratocystis pilifera andAureobasidium pullulans was studied. Kasugamycin showed a synergistic effect with benlate and euparen with all three microorganisms, thiolutin stimulated mainly the fungicide effect of euparen. Kasugamycin and thiolutin prolonged also the antifungal activity of benlate and euparen. Dithan decreased the activity of kasugamycin and thiolutin.     

Index of names of syntaxa typified in 1990

Following the “Index of new names” (Theurillat andMoravec 1993), the present work collects the names of syntaxa (in the sense of the Code of Phytosociological Nomenclature, BARKMAN et al. 1986) above subassociation rank typified in 1990. The list comprises 36 names of syntaxa; 2 names are given in addition to the “Index 1987” (Theurillat andMoravec 1990).     

Myosotis margaritae—A new species from Bulgaria

A new species ofMyosotis ser.Palustres M. Pop.,Myosotis margaritae, related to theM. caespitosa group, is described from Bulgaria. Diploid chromosome number (2n=20) is given for the new species, and notes on its distribution, ecology and taxonomic relationships are presented.     

Estimates of bacterial growth rate constants from thymidine incorporation and variable conversion factors

Thymidine incorporation into DNA is widely used to estimate rates of bacterial growth and secondary production in aquatic systems. The procedure requires the use of several conversion factors and assumptions to convert rates of thymidine uptake to rates of carbon production. Perhaps the most controversial of the conversion factors is that which converts rates of incorporation to the rate of cell production. During a year-long study in Lake Arlington, Texas, we empirically determined conversion factors from bacterial growth in filtered (1.0 m porosity) and diluted (1:9) lake water. Bacterial growth rate constants determined from changes in cell abundance were compared to growth rate constants estimated from empirically derived (both instantaneous and annually averaged), theoretical, and modeled conversion factors. Single value conversion factors (i.e., theoretical, or average of 19 empirically determined conversion factors) did not yield estimates of bacterial growth rate constants that compared favorably to growth estimates from changes in bacterial abundance. Conversion factors, determined from a regression model based on empirically determined conversion factors, gave annual growth estimates that were similar to those obtained from changes in cell abundance. Offprint requests to: T.H. Chrzanowski.