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Apoptosis and necrosis are only two ways by which eukaryote death is achieved. Certainly there are other ways. Say, if a tissue or organism burns, death is achieved before any nuclear changes, cell swelling or shrinking. Same thing goes with bacteria. Death is the generic term. If you have more details, you can be more specific. In laboratories, cells die ...


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The word bacteriocidal is commonly used when describing agents that kill them, as opposed to agents that slow their growth which are said to be bacteriostatic.


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Death is appropriate. Using this word to describe both unicellular and multicellular organisms places them in the same hierarchy. This hierarchy is the domain of life. Both prokaryotes and eukaryotes have unicellular and multicellular species. If you choose another word for death I would suggest not using it exclusively for bacteria. If a reader finds ...


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The word infect is an encapsulation of several activities: transcription, translation, viral entry, budding, lysis, etc. When you ask if a eukaryotic virus (influenza, ebola) can infect a prokarytoic cell (bacteria) you are asking if these viruses can do the same activities. The answer is no. Translation is mediated by ribosomes, which are different in ...


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I'm not so sure about my answer. But I think "bacteriophage" is a polyphyletic name of which was defined by the ability of infecting bacteria, but not defined by the genetic, evolutionary, or morphological relationships. It seems that if a species (or a taxon in a higher taxonomic level) of virus is infectious to bacteria, it will be classified as a member ...


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I assume you are asking if E. coli can survive extreme pH conditions and according to this study E. coli K-12 W3110 survives at pH 1.2 – pH 2.0 under low oxygen. This study cultured different strans overnight and exposed to pH 2.0 for 2 hours before diluting 1:80,000 and 1:400,000, under anoxic and aerated conditions. Dilutions where then plated allowing ...


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Fertilizer on tomatoes wouldn't make sense. Tomatoes are up above the soil, and fertilizer is usually applied to the soil before the plants sprout, but I've never seen an industrial tomato farm, so maybe they do spray fertilizer afterwards, but I would think pesticides or herbicides would be more likely. Fertilizer on carrots would make more sense, since ...


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An addition to the Alan's answer: some sort of selection for more resistant genotypes inevitably did take place and left distinct footprints in the human populations.


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The identification of the Black Death with plague is now fairly well-established - see this paper (open access) in which PCR and protein detection were used to detect the presence of Yersina pestis in human skeletons from plague-related mass graves across Europe. Outbreaks of plague do occur in rural environments, see this WHO page for some details. The WHO ...


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This question got me thinking about what are the metabolic enzymes that take oxygen up in E coli. I searched the metacyc database for reactions that consume molecular oxygen and there are only 3 that take in oxygen and one that produces oxygen. All three consumers of oxygen in E coli are the oxidation of ubiquinone by at two sites in cytochrome bcl or by ...


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The plasma membrane is quite permeable to oxygen and thus oxygen enters the cell simply by diffusion. Reactive oxygen species can be reduced enzymatically in aerobic organisms. Obligate anaerobes lack or don't produce sufficient quantities of these enzymes. An organism that doesn't use oxygen for metabolism but is also not relatively harmed by it can be ...


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The article and published work here and here respectively, reveals that E. coli replication is close to thermodynamic limits of efficiency having modelled this process using mathematical equations. However an interesting article and published work here and here, respectively reports a bacteria (homologous to Thermobrachium celere and Caloramator indicus, ...


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According to Wikipedia: 3 um long with a diameter of 0.5 um. That equates to a length of 30 000 A and a diameter of 5 000 A. http://en.m.wikipedia.org/wiki/Helicobacter_pylori


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I found that E. coli exposed to predators such as amoeba changes completely from normal form to filaments (on agar) that look wound up like spaghetti but are not only longer but significantly wider. In this form the predator can't attack E. coli and it lives among the amoeba for extended periods. It does not look like a simple point mutation to me, which ...


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Yes, this is possible and is researched as an alternative to antibiotics. It has been used experimentally before antibiotics became widely available. Research was abandoned when antibiotics became widely available. See for example here and here for reports on this. Today bacteriophages are researched for the treatment of bacteria which have a lot of ...


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This is a common experiment for microbiology courses and you can find instructions on the internet , here is an example from University of Wisconsin: http://inst.bact.wisc.edu/inst/index.php?module=Book&func=displayarticle&art_id=114 But the general method is measure optical density at regular intervals and plot them on a semilog graph, which has ...


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Is consumption of blood more "dangerous" compared to meat? Actually yes, a simple high dose of blood is enough to kill. The cause is, though it is most important thing to live when flowing the vessel, it's highly toxic when consumed. There are high chances of getting haemochromatosis or Iron overload. Source and More on this: ...


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I found these article, which show exponential increase in population of Vibrio in BP oil spill region (published in 2011 supported in 2013).$^{1,2}$ There is evidence that Vibrio representatives can metabolize oil-derived compounds $^{3,4}$. There is a sizable amount, more than 31%, where found in the Deepwater Horizon Spill.$^5$. Though the reason is still ...


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Efflux pumps are common in bacteria, as well as eukaryotes. The mutations included in their model would not include efflux pumps. A mutation could potentially affect the efficiency of a pump in a strain but the mutations in their model are not creating the pumps.


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As for how certain bacteria achieve their shapes, the cell wall plays an important role. Almost all bacteria have a cell wall made of a substance called peptidoglycan, a mesh of peptides and saccharides that provides rigidity and strength to the bacteria. This wall is produced through a complex series of steps that starts inside the cell, where the peptide ...


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The two amoxycillin formulations you mention pair the amoxycillin with a Beta lactamase inhibitor. This is because of the prevalence of resistance to beta lactam drugs including amoxycillin. If we were to invent a brand new never before seen beta lactam drug and started using it irresponsibly, there would probably be resistant bacteria within 5 years. The ...


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Here (mic.sgmjournals.org/content/127/1/121.full.pdf) is a link to a paper in which P. shermanii is grown in flask culture. Although the conditions are clearly designed to achieve low oxygen concentrations in the culture (the flask is almost full and is only shaken occasionally), they also indicate that oxygen is not toxic for this organism. Also, this is ...



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