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When differences between prokaryotes and eukaryotes are taught in an introductory biology course, a generic prokaryotic cell and a generic eukaryotic cell are typically compared. Cells in a complex multicellular organism, like a human, are quite diverse. Human red blood cells are one example of a highly specialized cell with a mature form that is quite ...


21

Could we use viruses that only affect bacteria to act as antibiotics? Yes. The specific class you're referring to is called a "bacteriophage". There's quite a bit of research going on surrounding phage therapy as a stand-in or replacement for traditional antibiotics. Here's a Nature Biotechnology article from 2004 that discusses your very topic. It is ...


17

An antibacterial is any compound that will kill or at least slow down the growth of strictly bacteria, a domain of prokaryotes. An antibiotic is often used synonymously, but denotes a compound that kills or slows down the growth of any cellular pathogen, prokaryotic or eukaryotic. So, certain antibiotics can kill bacteria, fungi and parasites but ...


14

Yes you could. It used to be a big deal before antibiotics were discovered, and continued for a bit in the Soviet Union. However, due to the success of antibiotics, it fell out of grace. Due to the lower level of applied research in the Soviet Union (not research itself, although equipment might have been often outdated a bit and the Soviets did isolate ...


12

No. The CDC recommends using a hand sanitizer at at least 60% ethanol. Most preparations used in the lab are 70% ethanol. Humans start to risk death somewhere around the 0.3% alcohol level (BAC), especially around 0.5%. People have gone higher, but even 1% BAC would be completely useless against bacteria. You'd be dead long before the bacteria died. ...


11

No. Prokayotic cells are full organisms with their own DNA, red blood cells are not.


10

In general antibiotics don't help with viruses. However, sometimes a bacterial infection may follow a cold virus, so there might be some scenarios in which antibiotics would be needed. However in many cases it could be due to people demanding antibiotics from their doctor. You can read more here (CDC site): http://www.cdc.gov/Features/getsmart/


9

What the comments are trying to say might go something like this. The antibiotic triclosan that's used in almost all 'antibacterial' products works pretty quickly - by interfering with several processes in the bacterial and fungal membrane. It doesn't need much more than contact to work. That being said, the longer your exposure to the antibiotic, the ...


9

I have worked in hospitals (US) most of my life, treating both community-acquired, and more pertinently to this question, nosocomial (hospital acquired) infections, and have read many articles on the subject. I have never, ever seen ants mentioned anywhere. People, flies, cockroaches and rats, yes. Ants, no. However, ants are vectors in a few foreign ...


8

A quick search on ISI Web of Knowledge yielded this paper: R J North, P A Berche and M F Newborg (1981) Immunologic consequences of antibiotic-induced abridgement of bacterial infection: effect on generation and loss of protective T cells and level of immunologic memory. Journal of Immunology 127: 342-346 The authors investigated the effects of ...


8

This is typically for a paper under embargo - it can be accessed by registered journalists so they can cover the original article when it is published. The paper is now published, so I changed the first answer. Before I go into the details, it is necessary to have a short look at the working mechanism of Vancomycin and the way bacteria got around it (which ...


7

The short answer is, as you found, that mitochondria are wrapped in a double membrane and are thus harder to penetrate with antibiotics. The long answer is some of them do. Good antibiotics target structures widely found on and conserved in bacteria that are not found in human bodies. Some antibiotics are a little less specific and can indeed interact ...


7

There are indeed antibiotics which have immunomodulatory side-effects, these are mostly from the class of macrolide antibiotics (erythromycin, clarithromycin, roxithromycin, azithromycin) and to some degree from the tetracyclines. Beta-lactam antibiotics (as Penicillin or Ampicillin) have not been shown to be immunomodulatory, but they are among the most ...


6

I agree with @Chris that this is mostly a matter of definitions - Greenfacts defines biocides as: According to the Biocides Directive (98/8/EC), biocidal products are those that are intended to destroy, render harmless, prevent the action of, or otherwise exert a controlling effect on any harmful organism by chemical or biological means. Examples ...


6

Ants can and do carry loads that are several times their own weight. I grew up in an area with a lot of ants, and a common scene was a long trail of ants acting as a food supply line. Once a morsel is located, they create a long feremone trail to that morsel. A large clump of ants is always working to break the food into smaller pieces, and several ants are ...


6

Yes, many times. For just one example, see this paper; you could also see this review for numerous examples. These are examples of spontaneous mutations that lead to antibiotic resistance, so this is sort of an extreme version of evolution of antibiotic resistance. You could also say that antibiotic resistance "evolves" in terms of selection any time an ...


6

Natural selection is environment-dependent. A mutation that makes an individual more fit in one context, might make it less fit in a different context. The mutations that make bacteria more fit in an environment where they're exposed to antibiotics generally make them less fit in a "natural" environment where they don't have to deal with antibiotics. That ...


5

Usually, resistance genes are located on plasmids---additional DNA rings in the bacterium that are part of the genome. These plasmids cause their own exchange with other bacteria, even from other species. B. clausii, the probiotics organism in question here, appears to be special, though, in that it has no plasmids. His resistance genes come with the ...


5

Triclosan binds to bacterial enoyl-acyl carrier protein reductase (ENR) enzyme, which is encoded by the gene FabI. This binding increases the enzyme's affinity for nicotinamide adenine dinucleotide (NAD+). This results in the formation of a stable, ternary complex of ENR-NAD+-triclosan, which is unable to participate in fatty acid synthesis. If ...


5

First, you present as fact that antibiotics therapy (say AT) does not reduce weight. To show this fact, a study must weigh persons before AT and after. Confounders to this measurement are 1. weight differences because of bladder content (up to around 1 liter urine = 1kg), 2. weight differences because of bowel content (100g-200g), 3. Food weight (up to 2kg ...


5

Are red blood cells prokaryotic? No! There are many more differences between procaryotes and eukaryotes than just the presence of a nucleus. See DeNovo's answer for more information. The terms procaryote vs eukaryote refer, not so much to the physiology of the cell but to a specific evolutionary lineage. Eukaryotes are individuals that belong to the ...


5

and there is not much evolutionary pressure to loose it The energetic cost of replicating antibiotic resistance genes in the absence of antibiotic selection is not trivial, and varies depending on the environment and genetic background of the strain. A good review can be found here. Beyond simple metabolic costs, there is some recent research that ...


4

I think this is mostly a semantic differentiation, when you look up definitions for antibiotics you can find very narrow which only include the classic and modern antibiotics, while others include almost everything which has an bacteriocidal (or also anti-fungal) effect, regardless of the mechanism. The Wikipedia article on antibiotics contains the ...


4

Short answer While sertraline may theoretically affect the immune system, there is no evidence, as far as I know, that it negatively impacts immune status. Background In the article (Atkin-Smith et al., 2015) sertraline (a.k.a. Zoloft, an antidepressant) is shown to block the formation of ‘beads-on-a-string’ protrusions and apoptotic bodies after from dying ...


4

For a natural immunity to evolve, two things have to happen: The immunity has to actually occur. That means all the necessary mutations will need to be there to grant this bacterium resistance to penicillin. For penicillin, for example, bacteria that evolved such a resistance evolved to produce the enzyme beta-lactamase. The immunity has to grant an ...


4

There are two general points that should be appreciated in relation to this question: Your statement that mitochondria “have prokaryotic ribosomes” is a misleading simplification. Although mitochondria and plastids are thought to be derived from eubacteria — and their ribosomes have some similarities in antibiotic sensitivity — the structures of their ...


4

The label of the veterinary product Fung-A-Way, which is Benzalkonium Chloride 0.15%, states that "Efficiency is neutralized by soap or detergent residues." The website http://www.mpbio.com has the following under its description for Benzalkonium Chloride: "Incompatible with anionic detergents, such as soap, and with nitrates."


4

If we assume all of these things could be practically done at least at some point in the future, here are the problems I see with the suggestions, and why they might not work (others may spot additional ones). 1 Translocation of a sabotaging 'agent' via the conjugation apparatus. This basically already exists, look up the various secretion systems of ...


4

Short answer: Yes, fluoroquinolones are chemotherapy drugs In layman's terms, fluoroquinolone antibiotics kill human cells as they divide. Fluoroquinolones are a class of drug called "topoisomerase interrupters." Every drug in this class is directly labeled as a chemotherapy drug except fluoroquinolones. This is not well known by the medical ...


4

Yes. The antibiotic (general microorganism “targeter”) you’re looking for is an antifungal. There are fewer ways to target fungi as opposed to bacteria, but we can target them nonetheless. The fungal cell membrane has ergosterol to regulate its permeability whereas the mammalian cell relies on cholesterol. Fungi have cell walls which are not present in ...


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