TRANSLATION: Antibiotics are drugs that are bacteriostatic or bactericidal. Both antibiotic types may be used to effectively eliminate an infection. Bacteriostatic antibiotics prevent bacterial growth and require higher dosages to eliminate the infection. Bactericidal antibiotics kill bacterial cells at lower dosages. A common cellular function that is targeted by antibiotics is the process of translation, since the ribosome and other factors involved in translation are different in prokaryotic cells versus eukaryotic cells. Thus, the antibiotic is specific only to bacteria and does not harm the host. Chloramphenicol is an antibiotic that blocks the enzyme, peptidyl transferase. This enzyme is responsible for forming peptide bonds between amino acids during the process of translation. Answer the following questions about chloramphenicol. a. Consider the specific role of peptidyl transferase and describe the exact point in translation that would be blocked in the presence of the antibiotic, chloramphenicol. i. Would the steps of initiation occur in the presence of chloramphenicol? Which steps? Are there steps that would not occur in initiation? If so, which ones?

You plan to synthesize a peptide to be used as a vaccine to treat melanoma, a particularly aggressive form of skin cancer. Normally, gp100, a protein on the surface of melanocytes, activates cell growth when it is bound by its ligand. Activation of the growth pathway depends on the presence of threonine in the ligand. The effective peptide vaccine will mimic the natural ligand, but won’t cause cell growth and division. Below is the sequence of the natural ligand:   LDMKTAG   In order to ensure your newly designed peptide vaccine does not cause cell growth upon binding, you must substitute the Threonine residue at position 5. What amino acid would you replace it with, bearing in mind that the peptide should still be similar enough to bind to the gp100 protein in the surface of melanocytes. Explain your choice. Your vaccine will be administered as a topical cream, and you require your peptide to have an overall neutral charge in order to be functional. At what pH should you formulate…

When choosing a "first line" drug to treat an infection, the most important characteristic would be? the specific mechanism of action bactericidal broad spectrum low toxicity (fewest side effects) In what cell type can both transcription and translation occur simultaneously? both prokaryotic and eukaryotic cells neither prokaryotic and eukaryotic cells prokaryotic cells eukaryotic cells

Prion diseases are caused by—     protein misfolding.     protein “melting” under heat shock.     protein degradation.     protein denaturation.     protein disintegration.

Each one gives some basic information and summarizes its main role in translation. mRNA:       Ribosome:

The required association of two α-globin molecules and two β-globin molecules to make a functionally active hemoglobin molecule is an example of     translational control.     post-transcriptional control.     post-translational control.     chromatin control.     transcriptional control.

Choose the false statement

In protein synthesis, DNA transcription records the genetic message, while ribosomal ______________ interprets the message. ________________ carries the genetic code to the ribosomes to facilitate protein/amino acid synthesis. The genetic message to make a  specific amino acid in a protein, is carried by a specific   three nucleotide unit on the messenger RNA called  a  During transcription, the nitrogen base adenine on the DNA bonds with the nitrogen base ______________ on the messenger RNA. The enzyme __________________ unwinds the DNA double helix in DNA transcription.

Glycophorins are a type of membrane protein found on red blood cells. They allow red blood cells to circulate through the blood vessels without sticking to the walls of the blood vessels or to other cells. Describe how a glycophorin protein would be synthesized by the cell. Include What parts of the cell are involved and what happens at each location. The process of protein synthesis (i.e. transcription, translation, etc).

Transcription and translation can occur simultaneously in the cytoplasm of a prokaryote. O 1) True O 2) False