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8

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 ...


7

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 ...


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 ...


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 ...


2

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 ...


2

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 ...


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 ...


2

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 ...


2

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 ...


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 ...


1

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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