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How Does Antibiotics Make A Bacteria Become Resistant? I Need A Reply Asap! (2 Viewers)

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How does the use of antibiotics cause bacteria to become resistant?

e.g. How does using antibiotics when they are not needed make bacteria to become resistant?
 

katie tully

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Stolen from Wikipedia

Antibiotic resistance is the ability of a microorganism to withstand the effects of antibiotics. It is a specific type of drug resistance. Antibiotic resistance evolves naturally via natural selection acting upon random mutation, but it can also be engineered by applying an evolutionary stress on a population. Once such a gene is generated, bacteria can then transfer the genetic information in a horizontal fashion (between individuals) by plasmid exchange. If a bacterium carries several resistance genes, it is called multiresistant or, informally, a superbug. The term antimicrobial resistance is sometimes use to explicitly encompass organisms other than bacteria.

Antibiotic resistance can also be introduced artificially into a microorganism through transformation protocols. This can aid in implanting artificial genes into the microorganism. If the resistance gene is linked with the gene to be implanted, the antibiotic can be used to kill off organisms that lack the new gene.
The four main mechanisms by which microorganisms exhibit resistance to antimicrobials are:

1. Drug inactivation or modification: e.g. enzymatic deactivation of Penicillin G in some penicillin-resistant bacteria through the production of β-lactamases.
2. Alteration of target site: e.g. alteration of PBP—the binding target site of penicillins—in MRSA and other penicillin-resistant bacteria.
3. Alteration of metabolic pathway: e.g. some sulfonamide-resistant bacteria do not require para-aminobenzoic acid (PABA), an important precursor for the synthesis of folic acid and nucleic acids in bacteria inhibited by sulfonamides. Instead, like mammalian cells, they turn to utilizing preformed folic acid.
4. Reduced drug accumulation: by decreasing drug permeability and/or increasing active efflux (pumping out) of the drugs across the cell surface.
 

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This should be in "The Search for Better Health".

Antibiotics kill or prevent many types of bacteria from growing. The correct antiobiotic must be taken for an infection because only one kind of antiobiotic will kill each group of bacteria.

The misuse of antibiotics, particularly using these drugs when they are not needed, has lead to antibiotic resitance in many populations of bacteria.

So... The incorrect use of antibiotics is the main cause of antibiotic resistence. This incorrect use includes:
- Using antiobiotics when they are not needed, for example to treat a viral infection (for which antibiotics are completely ineffective)
- Using the wrong antibiotic for an infection, for example using drugs prescribed for a different illness
- Not completing the full course of antibiotics so that slightly resistant bacteria are able to survive and resistance is gradually increased

For more information:
http://www.google.com.au/search?hl=...=1&q=developing+antibiotic+resistance&spell=1
 
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in any population there is natural variation, i.e. some bacteria have natural resistance to the antibiotic. those bacteria survive to reproduce, and their offspring also have that resistance, and they reproduce. therefore, over time, the antibiotic becomes ineffective in killing the virus.

a couple of examples for you: multi drug-resistant tuberculosis and MSRA a.k.a. 'golden staph'.

hope that helps :)

EDIT: bugger. beaten to the post, lol
 
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dolbinau

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So specifically, I think the issue with incorrect/overuse is the more you do it, the more likely you will expose it to a population where members are resistant; they reproduce and the trait becomes more common.

When, without overuse/incorrect use these mutations would be quite uncommon in the population and the population does not 'evolve' as it isn't common. (And the little resistant members eventually die over time - the trait gone)

Is this correct? I understand the concept of Antibacterial resistance but specifically related to 'over or incorrect use' I'm not 100% sure about.
 

axlenatore

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dolbinau said:
So specifically, I think the issue with incorrect/overuse is the more you do it, the more likely you will expose it to a population where members are resistant; they reproduce and the trait becomes more common.

When, without overuse/incorrect use these mutations would be quite uncommon in the population and the population does not 'evolve' as it isn't common. (And the little resistant members eventually die over time - the trait gone)

Is this correct? I understand the concept of Antibacterial resistance but specifically related to 'over or incorrect use' I'm not 100% sure about.
Over use is related to was the poste above you said, if you are using antibiotics more than you should you are just allowing the resistant bacteria to become mroe previlent in a population, as bacteria when they multiple not only replication identically but can transfer plasmids (bacterial DNA) between baterical cells so a resistant baterica cell can pass a plasmid containing the gene for antibiotic resistant to a cell without thereby making it resistant
 

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dolbinau said:
Is this correct? I understand the concept of Antibacterial resistance but specifically related to 'over or incorrect use' I'm not 100% sure about.
Also, I know that the question asks for antibiotics, but if it didnt you can talk about the overuse of antibacterial soaps and stuff.

Really, the only place antibacterial soaps should be used is hospitals - golden staph used to only be hospital based, but is now found more commonly in society due to dettol and shit

Incorrect use refers to not taking the whole treatment (ie stopping taking antibiotics after you start feeling better rather than when the doctor tells you). Although the antibiotics cannot fight off the resistant bacteria, while you are taking them your body is more likely to be able to, as the antibiotic kills off all the non resistant bacteria. If you stop taking your antibiotics too early, the resistant bacteria are more likely to replicate, so your body cannot fight them off
 
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It's really important to remember that natural selection is the mechanism by which bacteria evolves to survive.

(Not in direct relation to the question)- In every population there are organisms with specific traits eg. resistances. Within a poplation of bacteria, some of them will carry a gene which makes them resistant. By using the antibiotic on the bacteria you are essentially fuelling natural selection by killing the "weaker" organisms and allowing the "fitter" ones to slowly build and become the majority.

In response to the actual question the use of antibiotics can create disease resistance organisms. Once the organism is resisant (random mutation in response to environmental pressures - the antibiotic) it will build a population as stated above.


By using antibiotics when not needed such as in low uncontrolled dosages which havn't been prescribed, this potentially exposes the bacterial to a dosage which may not effectively "kill". With this prolonged exposer comes the mutation and hence the resistance through natural selection.

Hope this helps. Good luck with the exams.

Cheers.
 
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syriangabsta

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Shadose said:
I emphasise this simple answer
well of course you would, but in the end, the answer is natural selection.

what you're going to do is shove natural selection in there, give a defentiion then throw in examples and relate it to the question..

i wasnt answering the question, i was simply showing the basis of the answer
 
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syriangabsta said:
well of course you would, but in the end, the answer is natural selection.

what you're going to do is shove natural selection in there, give a defentiion then throw in examples and relate it to the question..

i wasnt answering the question, i was simply showing the basis of the answer
Your answer was fine as it allowed the op to research the evolutionary mechanism of natural selection. The emphasise on the 'simple answer' creates a false sense that the whole process can be answered with two words. Nothing agaisnt a succinct and concise post as long as it doesn't completely detract as emphasising does.

Study Hard... Not long now...

Cheers.
 

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WantToDoBetter said:
Emphasise all you like, write "Natural Selection" in the exam to a question like this and see how many marks you get.
It depends on the number of marks allocated
 

syriangabsta

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pffft, in bio you should write as much as you can. the only thing stopping you is your self. time isnt a factor in a biology exam, throughout all the past HSC exams for bio, i can finish them and have at least 1 to 1.5 hours to spare, and get a mark close to 90
 

Shadose

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hmm okay...
Do you usually need to ask for more paper?
 

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Re: How Does Antibiotics Make A Bactria Become Resistant? I Need A Reply Asap!e

i woulda just wrote about natural selection and how there is variation in every species of bacteria.. some are already immune so the use of antibiotics kills of the non-resistant strains and the remaining resistant ones survive, reproduce and prosper over time.. wouldnt this be enough for 2-3 marks

and whats all this about incorrect use of antibiotics? someone explain this to me please

like, how would using antibiotic on a virus (which is ineffective) or using the wrong antibiotic on a bacteria lead to bacteria becoming resistant? dont remember learning this lol

wouldn't incorrect use be like midifile said and mean not taking whole course of antibiotics etc.?
 
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syriangabsta

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Shadose said:
hmm okay...
Do you usually need to ask for more paper?
no. i dont write tooo big. i answer the q, thats what im supposed 2 do...

altho i do often (more like always) write far beyond the amount of lines im given lol
 

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