The antimicrobial activity of silver nanoparticles against E. coli was investigated as a model for Gram-negative bacteria. Bacteriological tests were performed in Luria-Bertani (LB) medium on solid agar plates and in liquid systems supplemented with different concentrations of nanosized silver particles. These particles were shown to be an effective bactericide. Scanning and transmission electr...

We introduce a methodology based on the Luria-Delbruck fluctuation model for estimating the cell kinetics of clonally expanding populations. In particular, this approach allows estimation of the net cell proliferation rate, the extinction coefficient and the initial (viable) population size. We present a systematic approach based on spatial partitioning, which captures the local fluctuations of...

Radiation studies of vaccinia virus were carried out using two types of radiation, Coao gamma rays and ultraviolet light (UVL). When virus particles were irradiated with gamma rays a two-component survival curve was obtained. The capacity of Earle’s L cells to support the growth of vaccinia virus was relatively sensitive to gamma rays. Infectious centres formed by infecting L cells with vaccini...

Fifty one years ago, Luria and Delbrück published in Genetics a paper that was to become a classic. In it they proved, beyond all reasonable doubt, that bacteria were mutating to phage resistance long before they could have encountered any bacteriophage. Luria and Delbrück also showed how the same experimental data could be used to estimate bacterial mutation rates. Since that time and in many ...

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) in food has provoked a great concern about the presence of MRSA in associated foodstuff. Although MRSA is often detected in various retailed meat products, it seems that food handlers are more strongly associated with this type of food contamination. Thus, it can be easily postulated that any food could be contaminated with thi...

To test the hypothesis that genetic instability correlates with malignant potential, we compared the rate of generation of marker chromosomal abnormalities in clones of B16 F1 and B16 F10 murine melanoma. These rates were estimated through an adaptation of fluctuation analysis of Luria and Delbruck (S. E. Luria and M. Delbruck, Genetics, 28: 491-511, 1943). The highly metastatic F10 line showed...

Bacillus cereus was used to remove Cr(VI) in tannery wastewater containing medium at different initial Cr(VI) concentration, temperature, pH and biomass to get better conditions. At the optimum condition, the Cr(VI) in tannery wastewater was treated by each component of the cells to detect the capacity of the components for the Cr(VI) reduction. Also, the Bacillus cereus was continuous cultured...

Most geneticists can easily name a dozen papers that transformed their field. Many of these papers continue to be reprinted and commented upon by historians, philosophers, literary critics, science technology and society scholars, and biologists. Such papers include Mendel’s 1866 plant hybridization paper; Sutton’s 1902 synthesis of Mendel with meiosis, which thereby coupled chromosomal mechani...