Narrow-Spectrum Antibiotics

The antibiotics will have different zones of inhibition on different bacteria. Also, a range of concentrations of the nutrients in the bacteria will change the bacterial growth.

Antibiotic resistance evolves in bacteria. Charles Darwin created the theory of evolution which focused on natural selection being the key factor of how things change. Natural selection is when organisms that are better suited to the environment are able to reproduce successfully. Evolution is descent with modification. Bacteria can become resistant to antibiotics by a mutation. The bacteria that did not die from the antibiotic inherited the gene from an ancestor that made it resistant. Since the other bacteria is dying faster than the resistant bacteria, the resistant bacteria are able to multiply

The misuse and overdose of the antibiotics increase the resistance problem. It can cause these bacteria to

The video “Program Four: Creators of the Future” talks about microbes in general; especially how some of them are resistant to antibiotics in various circumstances. Microbes are all around the world, even inside us. Many microbes are beneficial to humans but some of them are not. They are mostly associated with illness and because of that, in 1928 Alexander Fleming invented penicillin, which is an antibiotic produced by mold. Penicillin was the first microbial product to kill human diseases. Some microbes are resistant to all antibiotics and cannot be treated. When penicillin functions correctly, it kills the bacteria by destroying their cell walls. Microbes reproduce by replicating themselves in two; when a mutation in the replication occurs, what happens is that the microbe with the mutation is going to be resistant to all antibiotics known for the moment. Nothing will stop microbes from mutating;

This then means that the illness can spread, because the antibiotic has not succeeded in curing it. The way that bacteria form this type of resistance can be explained through natural selection. To start with, there are variations in the bacteria in the way that some are able to resist the antibiotic and some are not. When the bacteria come into contact with an antibiotic, those that are resistant will survive, while the rest will die. These selected bacteria then pass on the characteristics that allow them to resist the antibiotic. This means that over time, the antibiotic will become ineffective against a larger percentage of the bacteria. A new resistant strain of the bacteria has been formed that can survive even when treated with antibiotics, therefore enabling it to be passed to other people. The main cause of this is the overuse or misuse of antibiotics, which allows the bacteria more of a chance to develop a resistance. Some bacteria such as those found in the digestive tract, are naturally resistant to types of antibiotics. Illnesses that have previously been easy to cure with antibiotics are now harder to treat due to antibiotic

Any mutation that would prevent the action of antibiotics, but not at the same time provide a selective advantage to the bacteria, would be one that interfered with the bacteria’s ability to reproduce. If this were to occur, then any selective advantage would be negated by the cell’s inability to take advantage of the diminished competition caused by the death of susceptible bacteria. This would be likely to occur in reaction to an antibiotic that interfered with protein synthesis, since it would also impact on the chain of reactions that occurs in the transformation

Antibiotics target specific structure or process of the cell. Such as, inhibition of cell wall synthesis, Inhibition of protein synthesis, Injury to plasma membrane, & Inhibition of nucleic acid synthesis. These drugs include, such as B lactam drugs that are bactericidal & kill bacteria by interfering with the synthesis of the cell wall, Polymyxin B drugs that injures the plasma membrane allowing the cell to burst. Tetracycline & Chloramphenicol that are bacteriostatic drugs, and inhibits protein synthesis. Fluoroquinolones & Rifamycin that are bactericidal drugs & interfere with the synthesis of nucleic acid. The pathogens can develop resistance against these drugs that are used to treat them. Resistance to antibiotics can be acquired by mutation

First, previous exposure to antimicrobial agents such as antibiotics and antimicrobial cleaners only kill some of the bacteria if they are not used properly which allow some of the bacteria to become resistant to that drug or agent. The bacteria is then able to mutate so that they become resistant to them (Treas & Wilkinson, 2014).

Genetic change in a bacterium can have an effect in resistance. Most bacteria work by inactivating an essential bacterial protein. Genetic change can remove that protein and also mutations in the target protein can prevent the antibiotic from binding. Production of the antibiotics target enzyme can also be increased by genetic change meaning that there are too many and the antibiotics cannot inactivate them all. Not only

Once bacteria is exposed to an antibiotic, the sensitive bacteria are killed, but sometimes not all the bacteria are killed and those colonies that survive, are left to multiply. Bacteria can become resistant through many mechanisms, it depends on the bacteria. Some bacteria fight the drugs and push them out, others alter the attack site which makes the antibiotic unable to harm the bacteria in a way it did before. The attack site is altered when the bacteria has a stronger defense than the antibiotic has (Rice, 2006). If repeatedly exposed to antibiotics, this process allows selective pressure to occur which makes it more likely for the bacteria to mutate. Selective pressure is a process the bacteria take to become immune. Sometimes, however,

Antimicrobial resistance is the ability of a microorganism to withstand the effects of an antibiotic drug in which it was originally sensitive to. Resistant organisms are able to withstand attack by antimicrobial drugs such as antibiotics, antifungals, and antivirals which makes standard treatment procedures ineffective. Antimicrobial resistance is something that has evolved naturally via natural selection through random mutations, it can also be achieved by applying an evolutionary stress on a population. Once a gene mutation is generated, bacteria can then transfer genetic information horizontally, between individuals, by plasmid exchange. When a microorganism carries multiple resistance genes, it is

Resistance via modification of the anti-microbial compounds: Bacterial pathogens have evolved strategies to chemically modify the antibiotics via the production of enzymes that adds specific moieties to the compounds, inhibiting their therapeutic effects (Jose at al., 2015). These enzymes exert their action through the process acetylation, phosphorylation and or adenylation to sterically hinder the compound so it is no longer able to bind its target. Due to these biochemical reactions, the drug is unable to bind its target sites and thus results in increased resistance and higher MICs among bacterial populations (Wilson, 2014;

Antibiotic resistance will kill 300 million people by 2050. Antibiotic resistance appears when an antibiotic resistance loses the strength to effectively manage or kill bacteria and bacteria growth. There are some antibiotics that are naturally resistant to the human body. There are two other ways your body could become antibiotic resistant, 1) by genetics or 2) by acquiring resistance from other antibiotics. Many people ask how antibiotic resistance spreads. It can spread “vertically” which is a new generation that inherits antibiotic resistance genes. It can also spread “horizontally” is when bacteria share or exchange sections of genetic material with other bacteria.

A serious public health problem is the rise in antibiotic resistance. Some bacteria that can cause serious disease are becoming resistant to most commonly available antibiotics. Antibiotic medications are used to kill bacteria, which can cause disease and illness. A major contribution to human health is antibiotic medication. Many diseases that once killed people in the past can now be treated effectively with antibiotics. However, it has come to the surface that some bacteria have become resistant to commonly used antibiotics. Antibiotic resistant bacteria are bacteria that are not controlled or killed by antibiotics. They can multiply and even survive in the presence of an antibiotic. Most infection-causing bacteria can become resistant to at least some antibiotics. Bacteria that are resistant to many antibiotics are known as multi-resistant organisms (MRO). (Antibiotic Resistant bacteria, 2017)

Bacteria that are able to develop or acquire (through lateral gene transfer) a stochastic mutation that enables antibiotic resistance are more likely to survive and mature to replication stage and are therefore favoured by natural selection (Antimicrobial Resistance, 2013). These strains are then able to outcompete antibiotic susceptible bacteria in environments with antibiotics present to replicate to continue to harm the infected organism. Some mutations in the bacteria allow it to produce chemicals (enzymes) that inactivate antibiotics, while other mutations eliminate the cell target that the antibiotic attacks.