Effect Of E. Coli On Antibiotic Resistance

The development of antibiotics was an important advancement in 20th century medicine. Previously deadly infectious diseases are now routinely treated with antibiotics. Moreover, for modern-day medical procedures such as chemotherapy treatment to be successful, antibiotic use is necessary. For these reasons, the prospect of bacteria developing widespread resistance to antibiotics is a major concern as it would render many modern-day medical therapies unviable.

The third and final factor in bacterial resistance to antibiotics is bacterial genetic exchange. It is very common for bacteria to share genetic info between cells even if the bacteria are not the same species. When this happens, genes and DNA get mixed into different species allowing more mutations against the antibiotics.

When antibiotic is used most of the bacteria die but a few bacteria with antibiotic resistance gene survive and reproduce and pass this advantage to their offsprings. This selective pressure exists naturally, however antibiotic misuse can be accused for fastening the spread of the antibiotic resistance gene [Refer to figure 2] (Learn Genetics 2015). Consequently, inappropriate antibiotic intake will lead to a greater chance of superbugs being developed. Antibiotic resistance can be defined as a new ability which a bacterium has developed to stay unattached in the presence of an antibiotic that was previously effective to destroy the bacterium (ABC science 2015). Four key mechanisms that has been identified for bacterial antibiotic resistance can be listed as: producing enzymes that inhibit the functionality of the drug, reducing the effectiveness of the drug by producing targets against which the antibiotic, reducing the permeability of the drug into the bacterium and active export of antibiotics using various pumps (Pogson 2012). All these mechanisms can be developed by any of the bacteria when the corresponding mutated gene of antibacterial resistance is received. The genes code for specific proteins, and variation in the gene leads to alteration of the shape of proteins. This leads to changing the functionality

In doing research for an example of natural selection, I came across antibiotic resistant bacteria. This has become one of the biggest threats to the healthcare community and Center for Disease Control. Through the use of antibiotics in treatments that are not necessarily bacterial infections, as well as the over use and misuse of antibiotics, bacteria have evolved in ways making the antibiotics used against them useless. If a bacteria manages to survive through a dose of an antibiotic, they are capable of mutating and can transfer their DNA to other bacteria. The new bacteria multiply quickly and spread to other parts of your body or outside of your body to a new host. Once the bacteria have mutated and its DNA has been transferred to

The overconsumption of antibiotics is a big contribution to drug resistance and is why users should know what happens with the repeated use of these drugs. Even though some bacterial mutation occurs naturally, human use of antibacterial is the cause of higher-levels of resistance (Alliance for the Prudent Use of Antibiotics 2014). Bacteria mutate either by genetic mutation or by receiving the defensive agent. During an infection bacteria multiply naturally within the body and when exposed to antibiotics, bacteria have an opportunity to adapt to the drug (Alliance for the Prudent Use of Antibiotics 2014). During this period of

Like any other organism, bacterium are subject to evolutionary pressure. Antibiotic resistance in bacteria is rarely the result of a single mutation leading to full resistance, but rather the result of a series of mutations that incrementally increased antibiotic resistance. For example, in the case of fluoroquinolone resistance, resistance started with a mutation in the efflux pump, granting Streptococcus pneumoniae the ability to survive certain treatment regimens (13). This became an issue when people started to misuse their antibiotics. In this particular example, because patients did not follow their prescription regimens, they only killed the bacteria not resistant to fluoroquinolone. This selective pressure drove bacteria to further develop fluoroquinolone resistance, meaning that the initial infection remained untreated, and would now require a

Bactericidal antibiotics kill bacteria by interfering with the cell wall or organelle formation. (News Medical, 2004) Bacteriostatic antibiotics interfere with the cell’s metabolic processes, such as DNA replication and protein synthesis. (News Medical, 2004) Both actions inhibit the cells vital processes, causing cell death. (Crierie & Grieg, 2010) However, superbugs, such as strains of Staphylococcus aureus, and Mycobacterium tuberculosis are deadly as they are very difficult to treat due to their resistance to multiple antibiotics. (NPS MedicineWise, 2012) Previously, Staphylococcus aureus was treated with benzyl penicillin. Currently, however, the bacteria cannot be controlled through this method, as they have developed resistance, which occurs because bacteria have the ability to mutate. After antibiotic contact, bacteria can alter their DNA in a way that enables them to resist the antibiotics. Bacteria are prokaryotic organisms and produce asexually by binary fission, thus their offspring have no genetic diversity. The only source of genetic variation in bacteria is through mutation. (Crierie & Grieg, 2010) Mutation refers to changes in gene sequences, resulting in variation in subsequent generations. This process occurs in every millionth to ten-millionth cell. (Alliance for the Prudent Use of Antibiotics, 2014) Certain types of mutations cause different types of resistance. They may enable

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

For a bacterium to become resistant a change in its DNA must occur. This can happen in more than one way. Bacterium may gain resistance through spontaneous mutation within the bacterium’s DNA. This occurs when a single amino acid that makes up a protein changes arrangement, the order of the peptide chain (made up of amino acids, joined together to make up proteins) then the purpose of the protein in the DNA changes. This causes the genetic makeup of the cell to alter. If the mutation is of benefit and gives the bacteria resistance, once all the other none resistant strains of bacteria are killed, the resistant bacteria multiplies and reproduces, creating a new strain of bacteria which is resistant to the antibiotic in hand. Once a resistance gene is obtained and inserted into the DNA, the bacterium can dominate other bacteria and

Today, the use of antibiotics is very common. The gene that causes antibiotic resistance typically arises naturally or from a mutation. When bacteria are exposed to antibiotics, the bacteria with antibiotic resistance genes within the plasmid survive; this is called selective advantage. This process of the survival of bacteria that are resistant to antibiotics is a method of natural selection, causing more antibiotic resistant bacteria to be reproduced. They are rapidly reproduced by binary fission, conjugation, transformation,

Antibiotic resistance is a growing problem throughout the globe. Besides using antibiotics for medical use, they are being used in the agriculture industry. In animals, antibiotics are being used to treat diseases, but also to prevent diseases from occurring and to increase the growth of animals (Mehndiratta, 2014, p.340). In recent years, the evidence of farmers using antibiotics for non-traditional ways has sparked major controversy. In agriculture 90% of antibiotics are used for growth-promoting and prophylactic agents with the other 10% being used to treat diseases (Khachatourians, 1998, p.2). To understand why this occurs, we first must understand the genetic basis for antibiotic resistance and the occurrence of antibiotic resistance in selected organisms. By farmers doing this an increase in the number and types of microorganisms resistant to drugs, has increased public health problems. Finally, management options for reducing antibiotics in the environment have to occur. If farmers continue to use antibiotics for non-traditional uses, as humans we can be affected greatly not just by food supply, but by water runoff, the air, and even the soil. Also, more public health problems will occur.

Each time an antibiotic is used it creates a “selective pressure” on the microbial community. The bacteria, which are susceptible to the antibiotic treatment, will be killed. This allows for the non-susceptible bacteria to grow without competition, and accordingly become the dominant population (8). Antibiotic resistance in bacteria occurs by two mechanisms. The first mechanism is a rare mutation in the genome, which allows the cell to

Antibiotics are derived from microbes that work by inhibiting the growth or by killing other bacteria (Tortora, Funke, and Case 549). Usually our body’s immune system is an ample defense by stopping microbes from replicating or killing them. However, sometimes the body can become overwhelmed and that is when antibiotics are used to help out our immune systems. An important dilemma in medicine is the increasing occurrence of antibiotic resistance, which occurs when bacteria are exposed to the same antibiotics over and over and eventually makes them less effective (Tortora, Funke, and Case 549). Antibiotic-resistant bacteria are bacteria that are not killed by common antibiotics (“Antibiotics”, 2007, para.6). There are several ways bacteria can develop antibiotic resistance: by altering of the drug target, altering membrane permeability, by developing enzymes that can inactivate the drug, developing alternate synthetic pathways, or acquire resistance by exposure to microbe with resistance genes. This spreading of genes is the result of plasmids that transfer R factors which contain two groups of genes: a resistance transfer factor and the r-determinant, which has the resistance genes (Tortora, Funke, and Case 232). R factors can be a problem in the healthcare field because of the misuse of antibiotics. This leads to preferential selection of bacteria that have R factors and results in populations of resistant bacteria growing larger and larger (Tortora, Funke,

Antibiotics have the ability to kill or hinder the growth of bacteria. Antibiotics contain compounds that are naturally produced by organisms to combat diseases caused by microbes. Discovery of penicillin by Sir Alexander Fleming became the first stepping stone of many new antibiotics of today’s modern medicine. Antibiotics typically invade the very components that make up bacteria, such as cell walls and metabolic pathways (Sato et al., 2014). However, frequent mutations of bacteria cause today’s strains to become more resistant. One of many ways which bacteria undergo mutation is through horizontal transfer of genes (Lindsay J.A., 2013). The war against disease is a battle that humanity has fought for centuries, and only

However, the unnatural selective pressure of antimicrobials on microorganisms has resulted in microbial evolution consequently, leading to these agents losing their effectiveness against microbes as they adapt mechanisms to resist them. Mechanisms such as efflux pumps, modification enzymes and acquired resistance genes are common and can be transferred between microbes three main ways: transduction, transformation and conjugation (figure 1)