Question

Write an essay entitled ‘The structural hierarchy of proteins’. You should include a brief plan for your essay. In your essay you should explain each of the different levels of structural organisation found in proteins, describing the chemical and/or structural features of each and identifying the chemical bonds and interactions on which they depend. In addition, you should: refer to one technique that is used to study protein structure and briefly explain the kind of information that can be obtained from its application give one example each of a homomeric and a heteromeric protein. (You may use examples from Activity 1.1, but not IL-8 which was referred to in Book 2 Chapter 1). Include at least two simple diagrams to illustrate your essay. Please see the note about diagrams at the start of this TMA. Marks will be awarded for the clarity and relevance of the diagrams, labelling and appropriate reference to them in the text. A mandatory word limit of 1200 words applies for the essay. Please note that this is an upper limit and you should not feel compelled to write up to the maximum, as it should be possible to write a shorter essay that covers all the salient points. The word limit does not include the following: the essay plan; the essay title; words in tables, figures or diagrams and their captions; words in reference lists. However, the word limit does include in-text citations. You should perform a word count and state the total number of words at the end of your essay. The 30 marks available for this question will be allocated as follows: Essay plan – 2 marks Essay: Introduction – 2 marks Body of essay (including diagrams) – 18 marks Conclusion – 2 marks References (including appropriate citations in the essay) – 2 marks Style and construction – 4 marks N.B. 10% of the marks for this question will be deducted for answers that exceed the mandatory word limit.

Answer 1

You can write your essay under following plan:

Introduction: You simply introduce about protein then go on to describe the need of hierarchical structure and how its evolution helps it to be a candidate for building blocks of organism structure and function. Then you have to discuss about amino acids with their properties which enables the different protein structures.

Composition of different amino acids: Here you can discuss about why amino acids have different classes and discuss about these classes.

Different bonds required for protein structure hierarchy:

Different levels of structure and their determining factors: such as shape etc.

Crucial protein structures for protein hierarchy: Discuss in following subheadings with examples (Linear structures, alpha helix, beta sheet and turns), motifs and secondary structures (helix turn helix, coiled coil motif, Zinc finger). tertiary structures and structure and functional domains,

Evolutionary and functional relationship between different proteins: Categorize different proteins with examples based upon sequence homology.

Conclusion: Summarize the essay with taking the gist of each headings with you view point.