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I've found a nice review that has many details on plasmid replication in general, and several papers about pSC101 in detail, and I'll try to extract the key information from these papers. First of all your plasmid as an ori region that contains so called iteron: In many cases, the origin of replication contains directly repeated sequences, termed ...


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there is a word symbiosis which means interaction between two different organisms living in close physical association, typically to the advantage of both.Often, especially with microbes, one organism lives inside another — the host. symbiotic microbesWhen both organisms benefit from the relationship, it is called mutualism. When only one organism benefits, ...


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usually the growth of bacteria is slowed down as they are in freezing temperature and they almost carry out no metabolic reaction at this stage.but another problem occurs that is ice crystals formation which disrupts or pierce the bacterial cell wall causing the death of bacterial cells,this problem can be solved by adding glycerol or any other ...


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Inspired by the answer by @MarchHo, I came to think of the contagious cancer that attacks Tasmanian Devils - Devil facial tumour disease - which should provide a very similar example to the clams in your question. I don't think it has been given a species name though, but for most purposes it functions as an independent species. This "organism" lives as a ...


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Cyanidioschyzon merolae seems to be an example of such algae. Cryptomonad, aka Cryptophyceae also lacks cell wall. I think, problem you encounter is that most studies are concerned with structure and function of cell walls, as such knowledge can be used in biotech industry. Hence, you will not find answer by looking for "algae without cell wall". As a ...


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Yes, they do. For a look at survival of Lactobacillus and other bacterial species after multiple freeze/thaw cycles, check out Harrison 1955 (below). The awesome hand-drawn graphs show that many bacteria survive after being frozen for 11 weeks. There's also a figure on the following page showing that many bacteria also survive after multiple freeze-thaw ...


8

I would consider HeLa cells to be an example of a unicellular eukaryotic organism that evolved from humans. It can survive independently and replicate within cell culture plates, but cannot survive in the wild, however. HeLa cells are, like in your example, cancer cells, in this specific case human cervical cancer cells. They were propagated as an ...


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Although I cannot definitively answer this question as I cannot account for every extant, or even extinct organism--trends in evolution would suggest that it is highly unlikely that a unicellular organism would have descended from one that was multicellular. Firstly, it is important to note that it is widely accepted that prokaryotic unicellular organisms ...


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This will be only a partial answer, I don't know about zoonosis. Probably, increase in population mobility helped in spreading disease. Planes, ships, movement due to wars allowed for higher rate of travel/migration, thus facilitating quicker spreading of the virus from continent to continent. See recent measles outbreak in California, US, started by single ...


1

Virulence factors of V cholerae is regulated by a hierarchical regulatory system. The proteins you listed in your question are part of this system. In this paper it is said that the actual activation of TCP and CT is done by ToxT- thus this could be your "key" protein. I'd also like to note that just because these are two different genes does not necessarily ...


1

If you're looking at evolutionary timescales, then the only available source of information is the target organism's genome sequence. At least some of the methods of horizontal gene transfer you mention leave a distinctive signature in the genome. For example, retrovirus particles that have become incorporated into the human genome are easily identified by ...


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To get to the membrane of these species you first need to get past a formidable cell wall. The methods listed below are therefore more aimed at making cells permeable but the membranes must sustain some damage in the process. At our lab we regularly use glass bead transformation for microalgae transformation. The microabrasion allows DNA to go in so I ...


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While not comprehensive, the Portal to Protistology has many resources for exploring the diversity of protozoa. I especially recommend their videos that are really fascinating, focus on distinguishing features of different protists, and may be helpful for identification to some degree. But given your interest you should just explore all the pages on the ...


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Since no one else decide to post anything that was put in the comments as an answer I decided to. There is an excellent article from Wikipedia on the subject, found Here. It was also recommended in the comments that you should read the sources provided. I also found this PDF to be quite helpful, Nebraska Med. I hope this helps!


4

Yeast can produce up to 16-17 v/v% ethanol without dying according to this article. Yeast is a primary industrial ethanol producer, it produces ethanol even under aerobic conditions, in contrast to bacteria that usually ferment sugar to ethanol under anaerobic conditions. Bacteria can also withstand up to several percent v/v concentration ethanol in their ...


2

I couldn't find any examples in humans (aside from mitochondria, if those count), but there are examples of varying degrees of intracellular endosymbiosis in insects, plants, and single-celled organisms. An example is Ca. Carsonella ruddii, an endosymbiontic bacterium of psyllids (a family of plant-feeding insects). The bacterium lives within specialized ...


3

Conjugation occurs between cells of the same species too. For this to occur cell have to be close to each other. Now, if you have an isolated population of bacteria that never gets in contact with an F+ bacteria then this population would stay F-. Also not all conjugation events are successful, mechanical perturbations can disrupt the pilus through which ...


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Survival of the host cell is in many cases dependent on the egress strategy of the pathogen. There are many examples documented in various species. The only case I found that's somewhat relevant to human cells was were mutant Legionella pneumophila, defective in the lytic pore complex, did not produce necrosis of the host cell. However, the cells did release ...



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