When overexpressed in Saccharomyces cerevisiae, beta-galactosidase fusion proteins directed to the mitochondria are toxic, preventing growth of yeast cells on non-fermentable carbon sources (Emr, S. D., Vassarotti, A., Garrett, J., Geller, B. L., Takeda, M., and Douglas, M. G. (1986) J. Cell Biol. 102, 523-533). We show that such fusion proteins interfere with the assembly of respiratory comple...

Bacterial populations contain persisters, cells which survive exposure to bactericidal antibiotics and other lethal factors. Persisters do not have a genetic resistance mechanism, and their means to tolerate killing remain unknown. In exponentially growing populations of Escherichia coli the frequency of persister formation usually is 10(-7) to 10(-5). It has been shown that cells overexpressin...

Gel electrophoresis has been used in studying protein components in crude cell fractions for metabolic studies (1, 2) and in determining the pur i ty of isolated proteins (3). While determining the feasibility of this method to locate the murine toxin in crude cell fractions of PasteureUa pestis, we observed that toxin activi ty was associated with more than one protein component of the patiall...

Unlike most bacterial species, Mycobacterium tuberculosis depends on the Clp proteolysis system for survival even in in vitro conditions. We hypothesized that Clp is required for the physiologic turnover of mycobacterial proteins whose accumulation is deleterious to bacterial growth and survival. To identify cellular substrates, we employed quantitative proteomics and transcriptomics to identif...

Diseases associated with unstable repetitive elements in the DNA, RNA, and amino acids have consistently revealed scientific surprises. Most diseases are caused by expansions of trinucleotide repeats, which ultimately lead to diseases like Huntington's disease, myotonic dystrophy, fragile X syndrome, and a series of spinocerebellar ataxias. These repeat mutations are dynamic, changing through g...

this study was performed to explore the presence of heavy metals in some popular herbal medicines of the iranian market. primarily, this study was planned to do the task by the usp method. in the second step, those plants which contained more than 10 ppm of total heavy metals were analyzed by atomic absorption method. in this study, 43 popular herbal medicines were investigated according to the...

Neurodegenerative disorders are characterized by accumulation of "toxic", pathologic proteins in brain cells. Mutations in genes coding these proteins result in conformational disturbances of the protein structure and their accumulation and aggregation manifesting at the level of light microscope as various intracellular inclusions. This paper is an attempt of approach cellular mechanisms under...

Protein damage segregates asymmetrically in dividing yeast cells, rejuvenating daughters at the expense of mother cells. Zhou et al. now show that newly synthesized proteins are particularly prone to aggregation and describe a mechanism that tethers aggregated proteins to mitochondria. This association constrains aggregate mobility, effectively retaining and sorting toxic aggregates away from y...

Bacillus thuringiensis Cry3Aa and Cry3Ca proteins have been reported to be toxic against the African sweetpotato pest Cylas puncticollis. In the present work, the binding sites of these proteins in C. puncticollis brush border vesicles suggest the occurrence of different binding sites, but only one of them is shared. Our results suggest that pest resistance mediated by alteration of the shared ...