The Ebola virus

Name :- Raj Gopal, Pratik Mane, Asad shaik. Group no:- 15 Part -I Q1. Which structural features are in common to all viruses, and which are not? Complete the table below to answer this question based upon the information provided in the case. Ans. Shared attributes Difference I) Required Host II) They have a capsid I) Have single or double strand II) May have enzymes III) Some have head and tail IV) Glycoprotein receptor Q2.Why are viruses considered parasites? Ans. A parasite is considered an organism that is harmful to its host. It’s a nonliving, but it can destroy the host’s cell it invades by multiplying until the cells are destroyed. They aren’t able to metabolize energy as well so they depend on the host. Q3. Examine the diagram of the viral particle below. Label all of the important structures on this virus that you identified in the table above. Ans. 1. envelope Glycoptotein spike, Matrix, RNP, Receptor 2. Capsid Protein 3. Envelope 4. Genetic material(DNA,RNA) Q4. Design an imaginary viral particle. Create a diagram of your virus and label its major features. Your virus should have a diferent capsid shape (e.g., icosahedral, helical, complex) than the one above and be non-enveloped. Ans:- Part II) – How Could a Virus Have Entered? Questions 1. Why is viral attachment to the host cell specifc between one virus and one type of cell? Ans:- viral attachment is to the host cell is specific between one virus and one type of cell because viruses have a host range. Viral attachment is specific due to the type of glycoprotein on the viral surface that specifically binds a host cell receptor on the target cell. 2. List several types of host cells and the associated virus that binds to the host cell. Ans:- influenza- uses HA protein to bind to host cell receptors on respiratory epithelial cells rabies- G protein to attach to receptors on neurons ebola- GP proteins to attach to receptors on different cells such as lymphocytes (macrophages and dendritic) etc. 3. What are three major ways in which a virus enters a host cell to deliver its genome Ans:- three major ways :- I) Direct injection of nucleic acid into host cell (DNA or RNA). II) Binding to membrane, fusion of viral envelope with host membrane to transfer genome. III) Endocytic pathway- bind with host cell membrane and brought into cell. 4. Formulate a hypothesis as to why there is more than one mechanism of viral entry into host cells. Ans:- If there was only one way in, it would most likely be easier for the cell to protect itself against it. Part-III Q1. 1. Describe the essential cell “machinery” that viruses use to make a new virus. Ans. Ribosomes and enzymes in host cell are used to make new viral genomes and viral proteins. viruses contain on a nucleic acid DNA and RNA and proteins. they don't have organelles needed to make viral parts. Q2. Why do viruses need the machinery to make more viruses? Why can’t they replicate on their own? Ans. viruses are not living cells (which means they don't encompass enzymes and organelles for replication/transcription) this is why they rely on the hose cell's machinery to make more viruses. Q3. What are the structures that need to be put together during viral assembly? Consider the key structures; components of viruses described earlier. Ans:- viral proteins, envelopes, capsid, glycoproteins, genomes. Q4. How does the army of new viruses get out of the cell to infect the nearby cells? Ans. there are 3 ways that the new viruses can get out of the cell: I) lysis (without envelopes) which is when the host cell breaks open II) budding at the plasma membrane (take pieces of host cell with them) III) exocytosis in vesicles that bud from the ER or golgi Q5. Examine the diagram below depicting viral infection of a typical cell. Ans. I. Viral attachment II. Entry III. Synthesis IV. Assembly V. Release They are pretty similar; one difference is the way of entry; Ebola always goes through an endocytic pathway. Also, the protein produced in an Ebola virus is specific to Ebola (VP40) Cellular factors are :- I.ribosome and II. viral receptor Part IV – The Ebola Wars. 1.Examine the diagram (Figure 4, next page) showing the life cycle of the Ebola virus. a. Label the five major steps used by Ebola virus to infect cells. In what specifc ways are these similar or different from those you labeled in the general virus life cycle? i)attachment ii)entry iii)synthesis iv)assembly v) release 2)Key similarities and differences: Ans:- a) They are pretty similar; one difference is the way of entry; Ebola always goes through an endocytic pathway.Also, the protein produced in an Ebola virus is specific to Ebola (VP40). b. Label the key viral and cellular factors in the indicated areas of the diagram. Describe each of their roles. Ans:- VP40- determines viral shape and interacts with capsid ribosomes- where protein synthesis occurs receptors- what the glycoproteins attach to glycoproteins- attach to specific cell receptor mRNA and RNA- also made at ribosomes. Formulate a hypothesis as to what would happen to viral replication and budding from the cell if the ribosomes did not make VP40, the viral replication and budding would not be infectious because it is not infectious to other cells without VP40. 3. What is one structural component of the Ebola virus to target for a vaccine that prevents infections like Terry’s?Explain your answer. Keep in mind the Ebola virus structures and that vaccines are developed to prevent viralinfections (for example, the fu vaccine contains a weakened form of the infuenza virus that does not causedisease). Ans:- VP40 as well as the genome need to be a target-the vaccine would need to have some form of both of these in order for our bodies to build resistance and prevent future infection.FL GP trimer, VP40, L, RNA Genome/ Ribosome, mRNA Part-V Q1. Synthesize the information provided above. Come up with an argument as to the best treatment plan for Terry. Ans. According to the information provided above the best treatment for Terry is immunotherapy. This is because the ZMAPP will be able to get attached to the glycoprotein on the Ebola and this will put a stop to a viral attachment which can happen to the cells. The ZMAPP will also help in protecting as there will be no entry of viruses or any viral replication.