Testing the Lysozyme Protein Crystal Growth

Testing the Lysozyme Protein Crystal Growth

Harrison Elkins Smith, 10/30/16

TA: Taylor Johnson

Abstract

        In order to further an understanding of macromolecules and their role in biology it is important to determine every aspect about them as possible. The mechanisms for creation, the conformation of atoms, products, reactants, rate of synthesis, and the functions of these molecules are just a few of the parameters that help identify the how’s and why’s of thermodynamics and kinetics of biological mechanisms. Lysozyme, a common protein that consists of digestive enzymes is produced in many organisms and is a primary factor for removing waste products from the body. This protein has been crystallized and studied through x-ray analysis many times to study its structure and conformation. In order to do so, obtaining good crystals would be optimum for analysis (insert citation).

        The hanging drop method was used for producing crystals using a sample of lysozyme. The conditions that were chosen to vary were the concentrations of sodium chloride and the pH of the total reagents. Six wells with solutions that consisted of increasing amounts of NaCl were to be compared to the same six solutions of another set of wells with solutions that had a different pH. This helps determine how NaCl affects the crystal process as well as the pH. The results proved to show us that NaCl does indeed affect growth at specific concentrations and that the pH affect the size of the crystals. Certain combinations of the two provide different results.

Introduction

        A large portion of understanding macromolecules involves determining the structure of its crystals through x-ray crystallography. For x-ray analysis to provide accurate results it’s highly desirable to view a high saturation of large crystals. In order to gather the best results it’s important to optimize the growth of crystallization. (insert quote) The attributes of the crystals produced can depend on several conditions. Temperature, pH, salt concentration, protein concentration and additional reagents are all factors that can alter the produced crystal’s composition.

This experiment involves testing two variables that are to be varied and studied for determining optimum crystal growth of the Lysozyme protein. It was hypothesized that increasing the concentration of NaCl would result in an increased quantity of crystals while differences in pH would have an effect of any kind on the crystals. To understand crystallization a lysozyme protein sample was used under specified solution compositions in order to determine which concentration and at what pH produces the most desirable results.