Detection of some chloroorganic compounds by a microbial sensor system

Cells of an isolated Pseudomonas sp. MB58 strain containing DL-2-haloacid dehalogenase were used as a biological component in microbial bioassay for the detection of 2,2-dichloropropionic and D-2-chloropropionic acids. The cells were entrapped in various matrices. The highest specific activity and stability have been obtained in calcium alginate. Temperature between 293 and 313 K did not affect the enzymatic activity of the cells, and pH between 6.0 and 8.0 had a little influence. Several organic substances did not influence the conversion, whereas some heavy metal ions inhibited the dehalogenase activity

Germline MSH2 and MLH1 mutational spectrum in HNPCC families from Poland and the Baltic States.

Peer reviewe

Combined Effect of Dietary Cadmium and Benzo(a)pyrene on Metallothionein Induction and Apoptosis in the Liver and Kidneys of Bank Voles

Bank voles free living in a contaminated environment have been shown to be more sensitive to cadmium (Cd) toxicity than the rodents exposed to Cd under laboratory conditions. The objective of this study was to find out whether benzo(a)pyrene (BaP), a common environmental co-contaminant, increases Cd toxicity through inhibition of metallothionein (MT) synthesis—a low molecular weight protein that is considered to be primary intracellular component of the protective mechanism. For 6 weeks, the female bank voles were provided with diet containing Cd [less than 0.1 μg/g (control) and 60 μg/g dry wt.] and BaP (0, 5, and 10 μg/g dry wt.) alone or in combination. At the end of exposure period, apoptosis and analyses of MT, Cd, and zinc (Zn) in the liver and kidneys were carried out. Dietary BaP 5 μg/g did not affect but BaP 10 μg/g potentiated rather than inhibited induction of hepatic and renal MT by Cd, and diminished Cd-induced apoptosis in both organs. The hepatic and renal Zn followed a pattern similar to that of MT, attaining the highest level in the Cd + BaP 10-μg/g group. These data indicate that dietary BaP attenuates rather than exacerbates Cd toxicity in bank voles, probably by potentiating MT synthesis and increasing Zn concentration in the liver and kidneys

Biological synthesis of metal nanoparticles

Nanotechnology has attracted a great interest in recent years due to its expected impact on many areas such as energy, medicine, electronics and space industries. One of the most important aspects in researching nanotechnology is a synthesis of metal nanoparticles of well-defined sizes, shapes and controlled monodispersity. One of the exciting methods is the production of metal nanostructures using biological systems such as microbes, yeast, fungi and several plant extracts. Biological systems provide many examples of specifically modified nanostructured molecules. Perhaps, the best known are the magnetotactic bacteria which intracellularly synthesize magnetic nanocrystals in magnetosomes. The production of many other metal and metal alloy nanoparticles by organisms is a consequence of detoxification pathways. Organisms have evolved specific mechanisms to prevent excessive accumulation of metals. There are two probable ways to capture or trap the metal ions, electrostatic interaction and/or secretion of substances that will adhere the ions. For the process of intracellular synthesis of nanoparticles, the ions are involved in a nutrient exchange and/or substance diffusion. Thereafter, the functional reducing agents (i.e. reducing sugars, fatty acids, glutathione, flavonoids, terpenoids, fitochelatines etc.) and/or enzymes (NAD+/NADP+- dependent reductases, hydrogenases, oxidases), convert the harmful ions into non-harmful matters. Finally, the nuclei grow and subsequently intracellularly or extracellularly accumulate to form nanoparticles. Despite numerous research made in this area, the mechanism of biosynthesis is not a fully understood. In this paper an overview of the use of living organisms in the biosynthesis of metal nanoparticles is given and different mechanisms leading to the formation of nanoparticles are demonstrated

Extracellular Biosynthesis and Antimicrobial Activity οf Silver Nanoparticles

The extracellular synthesis of silver nanoparticles using the cell-free filtrate of Penicilium sp. is reported. Our results suggested that the product could be used as an effective antimicrobial agent

Zastosowanie pleśni z rodzaju Penicillinum do biodegradacji związków chloroorganicznych

Halogenated compounds occurwidely in the biosphere either as natural products or as xenobiotic compounds entering the environment with the use of herbicides and pesticides. In recent years some microorganisms have been reported capable of degrading many of these substrates. Microbial growth on halo-genated compounds requires production ofcatabolic enzymes to cleave the carbon-halogen bonds. The objective of the present study was to examine the ability ofPenicillium sp. G3 (isolated from soil) to degrade chlorinated substrates. Penicillium sp. G3 was able to grow on the investigated halogenated compounds as sole carbon/energy source. Of these, mono-and dichloropro-panes were found to be the best carbon/energy sources. Of the chlorinated acids used for the purpose of the study, 4-chlorobu- tyric and 5-chlorovaleric acids were the best substrates for the growth ofPenicillium sp. G3. All the investigated compounds were degraded with the release of chloride ions to the growth medium. The best substrate for dechlorination was 4-cmorobu-tyric acid. The addition of glucose to the medium stimulated dehalogenation. The results showed that Penicillium sp. G3was not able to mineralize the chemicals tested. Thus, to provide complete mineralization it is necessary to use a mixed popu lation of fungi and bacteria. Having a remarkable ability to dehalo-genate a variety of chlorinated compounds, Penicillium sp. G3 may become an effective component of a mixed culture, thus initiating mineralization of the investigated chemicals

The impact of enterprises systems on sales performance: a study of ERP system implementations in Polish SMES

While having been the object of numerous studies, the link between ERP implementation and SMEs performance still requires understanding. This paper documents the effect of investments in Enterprise Resource Planning (ERP) systems on a firm’s sales performance and profitability measure such as return on sales (ROS). The models are based on a sample of 240 during time of defined activities in the sales process realized during the each month by 40 knowledge workers in each of 5 Polish SMEs announcements of ERP implementations. Our analysis of the financial benefits of these implementations yields mixed results. Our results are encouraging that we find the business activity that can persistent evidence of sales performance associated with ERP investments. This should help alleviate the companies that some have expressed about the viability of ERP given the highly publicized implementation problems at some firms