Plates Cephalexin Method

The peptidoglycan coat in bacterial cells is formed by a crystal lattice structure that forms linear chains from a pair of alternating amino acids. The cross linking of peptidoglycan strands by the transpeptidase enzyme forms an uneven cell wall. Antibiotics, notably penicillin, interfere with this cross-linking, which destroys the bacteria cell wall. More specifically, antibiotics work by attaching to specific sites on the ribosome, which affects with the bacteria’s function during protein synthesis. The small or 30S ribosomal subunit has binding sites for tRNA molecules. These sites are known as the aminoacyl (A), peptidyl (P), and exit (E) sites. The process known as “decoding” oversees base pairing between the codon of mRNA and the anticodon of tRNA at the A site, allowing the 30S subunit to distinguish between the similarities of the tRNAs (Brodersen et al). Because most antibiotics bind to ribosomes, its main target is the rRNA, which results in most of the binding sites being near the mRNA and the tRNA binding sites, or at sites that undergo structural rearrangements during the processes of decoding or translocation (Dallas et al). In all, the antibiotic prevents the bacterium from creating its cell wall, which essentially kills the bacterium (Brodersen et al).

Antibiotics either stop the bacterial cell from reproducing or kill the cell. They can disrupt the bacteria by deterring

All anti-infection agents utilized as a part of human treatment since the beginning of the anti-infection agents time in the mid 1900s can be partitioned into three unmistakable classifications as indicated by how they were eventually produced on substantial scale. These arrangements take after. Natural products: mixes made specifically by huge scale aging of microscopic organisms or parasites. Semi-synthetic antibacterial: compounds manufactured by chemical synthesis using as starting material a natural product. Fully synthetic antibacterial: exacerbates that are fabricated by completely manufactured courses (Wright, Seiple, and Myers, 2014).

One person each in a team of four heavily inoculated two Mueller-Hinton agar plates with one of the cultures listed by aseptic transfer from a broth culture using a sterile cotton swab. Each plate was marked off into four segments, a total of eight sectors. One McFarland standard disk containing one of the eight antibiotics tested was placed, using

Tetracycline (T-10) was only one measured at 18mm in diameter. This zone size falls in the category of Escherichia coli having an intermediate resistancy (Table 1) to the antimicrobial agent. **The only one that had any effect!

It also helps with the prevention of PCP in HIV-positive patients, but should be used cautiously due to the incidence of adverse reactions. This drug is also active against many strains of gram-positive pathogens including: Streptococcus pneumoniae, Staphylococcus aureus, Group A beta-hemolytic streptococci, Nocardia, Enterococcus. It also has activity against many gram-negative pathogens, such as: Acinetobacter, Enterobacter, Klebsiella pneumoniae, Escherichia coli, Proteus mirabilis, Shigella, Xanthomonas maltophilia, and Haemophilus influenzae, including ampicillin-resistant

found that both the drug and the bacteria use enzymes as their defense and attack

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

The primary function of antibiotics is to help kill pathogens that threaten the health of the individual. They do this by getting inside of the disease-causing organism and disrupting its vital processes. There are several ways to disrupt the processes, two major mechanisms will be discussed: One way is to interfere with cell wall synthesis. Beta-lactams are the class of antibiotics that perform this function. Among the Beta-lactams are penicillin and cephalosporin ("How do antibiotics work?" 1997). Another antibiotic mechanism is to interrupt protein synthesis. Tetracyclines and erythromyocin function in this way ("How do antibiotics work?" 1997). They belong to a class of antibiotics named aminoglycerides.

As we seen in the mechanism of action all beta-lactam antibiotics, share a basic chemical structure that includes a three carbon, one nitrogen cyclic amine structure is known as the beta-lactam ring. Beta-lactam ring attached with a side chain having a variable group to the core structure of by a peptide bond. The variation of the side chain contributes to antibacterial activity.FDA has approved over 34 beta-lactam compounds as active ingredients in drugs for human use. Beta-lactam antibiotics have the following five classes:

d. ciprofloxin: Contains agents that inhibit one or more enzymes in the DNA synthesis pathway

they are two procedure by which the antibiotic attacks the bacterial cells. one is by interfering which the bacterial ability to repair the damage DNA. by stopping the bacterial ability to make what it needs to grow new cells to make what it needs to grow. the other one is by weakening the bacterial's cells wall until it burst

Escherichia coli were incubated in penicillin for 30 minutes. The bacteria can get longer, but can’t divide. After a while, the weak cell wall will rupture. Penicillin V is an antibiotic that’s in the penicillin group. It fights bacteria in the human body. It fights many infections caused by bacteria, such as ear infections.

The main objective of this experiment is to investigate the effect of different types of antibiotics on bacteria Bacillus subtilis and Escherichia coli. Some of the main methods used in this experiment

Antimicrobial agents induce bacterial cell death by interactions between a drug fragment and proteins on bacteria. It can act on very specific stages of bacteria (Briand, 1978). Widely speaking, most antimicrobial agents can be classified in a variety of ways. It can be classified based on purely the chemical structure such as polypeptides, acyclic or glycosides. Other than that, it can also be divided based on its source: synthetic, semi-synthetic or natural forms. Another form of its division is based on its spectrum of activity, making it broad or narrow spectrum or based on the type of organism its effective against, such as gram positive, gram negative, aerobes or anaerobes species. An essential classification is based on its function on bacterial cell replication and also based on its type of actions, whether causing an effect on cell growth or directly cell demise. These two imperative classifications will be