The effects of antibiotics on bacterial growth
Intro
The aim of this document is to research the effects of different antibiotics and their
effect on bacterial growth. This is useful because in industry doctors or pharmacists
can prescribe their patient the best antibiotic for their condition they are suffering
with.
How are antibiotics used?
Some types of bacterial infections are treated or prevented with antibiotics. They
function by killing or inhibiting bacteria from reproduction and spreading. Antibiotics,
like common cold, influenza, many coughs, and sore throats, are not effective
against viral illnesses. Antibiotics have no effects on viral infections. This is due to
the fact that viruses are so simplistic that they rely on their host cells to carry out
their functions. Antiviral medicines, as opposed to antibiotics, function by interfering
with viral enzymes. (1) Many illnesses may also be treated without antibiotics but
with our immune system, therefore it's not recommended frequently. In order to avoid
evolution of an antibiotic resistance, antibiotics should be given and appropriately
administered. This means the treatment by one or more antibiotic types of a bacterial
strain no longer responds.
Antibiotics would be appropriate to treat bacterial infections if:
They are unlucky to clear up without the aid of antibiotics
If they could infect others unless treated
If bacterial infections takes too long to clear without treatment
If its carry’s a risk of more serious complications.
(2)
The NHS is a UK-based organisation that offers healthcare to all taxpayers, which in
turn reduces the cost of drugs and treatments because they are the exclusive
supplier (excluding private healthcare), and thus set the price. The chosen article
was authored by “NHS 24,” whose aim is to provide people in Scotland with
information on healthcare, services, and campaigns. NHS 24 would almost definitely
not be bias because they do not profit and so have no need to be bias. They would
also not be bias since it would harm the organization's reputation. It is also credible
information because experts produced this content with the intention of educating
others.
Betterhealth is a government-run organisation whose main goals are to provide
information on all illnesses and to assist individuals with anything from reducing
weight to stopping smoking. Taking this into account, I would say that the content is
reliable because it is written by experts in the industry for a respectable organisation.
It would also be unbiased since there is no reason for them to be bias. It would also
hurt the organization's reputation and they would be excluded from the scientific
community owing to their misinformation.
Types of antibiotics & how they work
,Prior to the 20th century, bacterial infections, including pneumonia, tuberculosis,
gonorrhoea, rheumatics, and urinary tract infections, were not effectively treated. In
1929, the first true antibiotic, penicillin was found by the bacteriologist Alexander
Fleming, which began a new medicinal age.
Ever since, scientists have found dozens of antibiotics that attack bacteria in various
ways. Many antibiotics (such as penicillin) work by attacking bacteria's cell walls. The
drugs accurately prevent bacteria from synthesising peptidoglycan, a molecule in the
cell wall that provides the wall with the strength it requires to survive in the human
body. However, there are several ways to inhibit peptidoglycan assembly —
vancomycin, for instance, furthermore, significantly interfere with peptidoglycan
assembly, not in the same way that penicillin does.
Other drugs prevent bacteria from successfully replicating DNA. Quinolones are an
antibiotic class that targets DNA gyrase, an essential enzyme that aids in the
unwinding of DNA for replication. Ciprofloxacin and related antibiotics efficiently
inhibit bacterial growth by eliminating gyrase from the equation.
Protein synthesis is inhibited by several antibiotics, including tetracycline, which is
used to treat acne, respiratory infections, and other diseases. The drugs accomplish
this by blocking essential chemicals from attaching to certain locations on ribosomes,
which are cell structures where protein synthesis takes place. The bacteria cannot
carry out essential tasks, such as asexual reproduction, without their proteins so the
bacterial growth stops.
Rifamycin, a type of antibiotics used to treat tuberculosis, exhibits a similar effect by
blocking the production of RNA (such as tetracycline), a molecule involved in the
synthesis of DNA into proteins in the body.
Other antibiotics work by preventing bacteria from generating folic acid, an essential
vitamin, or by disrupting with the structure of a bacterium's cell membrane, which
regulates how things enter and exit the cell.
(3)
This post was written by Joseph Castro, who works as a journalist for Live Science.
Live Science is a science news website owned by Future through Purch, a
TechMedia Network renowned for content marketing, thus I'd say this post is
unbiased according to the website's purpose of providing information and news,
which is generally impartial. Because of his high level of education and experience, I
would claim that the author of this post is also credible. He graduated from the
University of Hawaii with a bachelor's degree in physics and a master's degree in
science journalism from New York University. So, based on this information, I would
claim that this article is reliable and impartial.
Structure of bacteria
Single celled microorganisms are bacteria. As no nucleus or
membrane-bound organelles is present, the cell structure is
simpler than that of other organisms. Their genetic information is
instead contained in a single DNA loop. Some bacteria contain
an additional genetic material loop known as a plasmid. The
plasmid frequently includes genes that benefit the bacterium
,from other bacteria. It may include, for instance, a gene which resists the bacterium
to a certain antibiotic.
In accordance with their basic shapes, bacteria are divided into five groups: spherical
(cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes).
This can occur in pairs, chains, or clusters as single cells.
(4)
Microbiology society is a charitable association for scientists interested in
microorganisms, their effects, and their practical applications. The first person to
discover the substances of antibiotics was Sir Alexander Fleming and he is the
person who set up this organisation. I would argue, with this knowledge, that
because the significant aspect in this website is the distribution of information and
research to the many, this article is unbiased and credible.
Some common structures of bacteria are briefly described below:
1. Slime (extracellular polysaccharide): It is an extracellular substance loosely
linked to bacteria produced by some bacterial species, which makes it
possible for smooth and prosthetic surfaces, such as intravenous catheters, to
be colonised.
2. Capsule: Often this bacterial surface polysaccharide coating serves an
important function in avoiding bacterial phagocytosis.
3. Peptidoglycan (cell wall): This gives the bacteria's shape and rigidity. The cell
wall consists of N-acetylglucosamine and N-acetylmuramic acid.
4. Cytoplasmic membrane: It is a phospholipid bilayer that takes on several
activities, such as biosynthetic processes, of eukaryotes organelles.
5. Flagella: These provide bacteria the locomotive ability. The numbers and
locations differ.
6. Pilli: These projections protrude from the cell surface, which allows bacteria to
adhere to the surfaces of host tissue. Their affinity for various tissue surfaces
can be extremely selective based on their amino acid structure.
(5)
Assembly of peptidoglycan
This is an important stage for bacterial survival. The sequence of events is as
follows:
a) Synthesis starts with the production of a nucleotide-linked water-soluble
precursor (N-acetylmuramic acid) which is also used to transport the
cytoplasm of pentapeptide.
b) In the cell membrane (bactoprenol), the precursor is then connected to a lipid-
like carrier, where N-acetyl glucosamine is added to the NAM. It is mobilised
throughout the cytoplasm.
c) The subunit (NAM-NAG) of disaccharides is then joined to a glycan strand.
, d) The last stage is the transpeptidation reaction, catalysed by a penicillin-
binding protein (TBP) transpeptidase that connects the growth strand to other
enzymes.
(5)
This information was compiled by the employees of Columbia Institution in New
York, which is regarded as the sixth greatest institution of higher learning in the
world, with a 4 % annual acceptance rate. They specialise in journalism, literature,
and social sciences; therefore, I would argue that this essay is both factually true and
impartial because it is intended for students (therefore they would have nothing to
gain from it being bias). It would also be reliable because it is a well-established
university with experts in the selected subject of study.
Features between Gram-Positive and Gram-Negative bacteria
Characteristics Gram Positive Gram Negative
Gram Reaction Keep the crystal violet dye and Can be decolorized in order to take
stain it blue or purple. counterstain (safranin) and stain pink or red.
Cell wall The cell wall is approximately The cell wall is approximately 8-12nm thick.
20-30nm thick.
Cell wall texture The wall is smooth The wall is wavy
Peptidoglycan Layer It is thick therefore multi- The layer is thin (single-layered)
layered
Teichoic Acids Present Absent
Periplasmic space Absent Present
Outer membrane Absent Present
Porins Absent It occurs in the outer membrane
Lipopolysaccharide Very little amount High amount
content (LPS)
Lipid and lipoprotein Low due to bacteria have lipids High due to the presence of an outer
content linked to the peptidoglycan membrane
Mesosomes Noticeable Less noticeable
Flagellar Structure There are two rings in the There are four rings in the basal body
basal body
Toxin Produced Exotoxins Endotoxins or Exotoxins
Resistance to High Low
Physical Disruption
Call Wall Disruption High Low due to it requires pre-treatment to
by Lysozyme destabilize the outer membrane
Susceptibility to High Low
Penicillin and
Sulphonamide
Susceptibility to Low High
Streptomycin,
Chloramphenicol and
Tetracycline
Inhibition by Basic High Low
Dyes
Susceptibility to High Low
Anionic Detergents
