Calves were fed Escbericbia coli of bovine origin containing an R factor with resistance determinants found rarely in human and bovine populations. Some of these calves received tetracycline. Fecal samples from human subjects in daily contact with the calves were analyzed for the R factor, the bovine E. coli, and changes in the levels of tetracycline resistant coliforms. Crossover from the calv...

The folding mechanism of typical proteins has been studied widely, while our understanding of the origin of the high stability of thermophilic proteins is still elusive. Of particular interest is how an atypical thermophilic protein with a novel fold maintains its structure and stability under extreme conditions. Folding-unfolding transitions of MTH1880, a thermophilic protein from Methanobacte...

Two representative thermophilic bacterial strains (T1 and T2) were isolated from a one-stage autothermal thermophilic aerobic digestion pilot-scale reactor. 16S rRNA gene analysis indicated that they were Hydrogenophilaceae and Xanthomonodaceae. These isolated strains were inoculated separately and/or jointly in sewage sludge, to investigate their effects on sludge stabilization under thermophi...

AIMS To determine the microbial succession of the dominating taxa and functional groups of microorganisms and the total microbial activity during the composting of biowaste in a monitored process. METHODS AND RESULTS Biowaste (vegetable, fruit and garden waste) was composted in a monitored composting bin system. During the process, taxonomic and functional subpopulations of microorganisms wer...

BACKGROUND Proteins from thermophilic organisms usually show high intrinsic thermal stability but have structures that are very similar to their mesophilic homologues. From prevous studies it is difficult to draw general conclusions about the structural features underlying the increased thermal stability of thermophilic proteins. RESULTS In order to reveal the general evolutionary strategy fo...

A number of factors have been elucidated as responsible for the thermal stability of thermophilic proteins. However, the contribution of aromatic interactions to thermal stability has not been systematically studied. In the present investigation we used a graph spectral method to identify aromatic clusters in a dataset of 24 protein families for which the crystal structures of both the thermoph...

Understanding the mechanism of thermodynamic stability of an RNA structure has significant implications for the function and design of RNA. We investigated the equilibrium folding of a thermophilic ribozyme and its mesophilic homologue by using hydroxyl radical protection, small-angle x-ray scattering, and circular dichroism. Both RNAs require Mg(2+) to fold to their native structures that are ...

Water samples from clay storage jugs ("zeers") located in homes and at public watering stands ("sebeels") at streets, mosques, and schools were examined. Coliforms, fecal coliforms, and fecal streptococci were detected in 100, 69, 88, and 91.56% of the samples, respectively. The general microbiology of the water and some factors affecting microbial load were studied. The predominant bacterial g...

To evaluate the effect of cooled and chlorinated chill water for Campylobacter and coliforms at a middle-size processing plant which was considered to be difficult for eliminate pathogenic bacteria on carcasses, following three conditions were examined; keeping temperature at < 20, < 10 and < 10°C, and chlorine concentration at < 50, < 50 and 50 to 70 ppm during processing in experiment 1, 2 an...