Solvent content of protein crystals.

Evolution by gene duplication

On the size of the active site in proteases. I. Papain.

Publisher Summary This chapter explores that the changes that take place in the protein molecules during denaturation constitute one of the most interesting and complex classes of reactions that can be found either in nature or in the laboratory These reactions are important because of the information they can provide about the more intimate details of protein structure and function They are also significant because they challenge the chemist with a difficult area for the application of chemical principles The chapter reviews that the denaturation is a process in which the spatial arrangement of the polypeptide chains within the molecule is changed from that typical of the native protein to a more disordered arrangement The chapter also discusses the classification of protein structures: primary, secondary, and tertiary structures The primary structure is that expressed by the structural chemical formula and depends entirely on the chemical valence bonds that the classical organic chemist would write down for the protein molecule The secondary structure is the configuration of the polypeptide chain that results from the satisfaction of the hydrogen bonding potential between the peptide N-H and C=O groups The tertiary structure is the pattern according to which the secondary structures are packed together within the native protein molecule The term “denaturation” as used in this chapter is indented to include changes in both the secondary and tertiary structures

Some factors in the interpretation of protein denaturation.

Small Angle X-Ray Scattering

To understand how a protein performs its individual biological function, it is essential to know its three-dimensional structure As early as 1934, JD Bernal and Dorothy Hodgkin (then Dorothy Crowfoot) showed [Bernal, J D & Crowfoot, D Nature 133, 794–795 (1934)] that proteins, when crystallized, would diffract X-rays to produce a complex pattern of spots They knew that these patterns contained all the information needed to determine a protein–s structure but, frustratingly, that information could not be deciphered By comparing patterns from crystals containing different heavy-metal atoms, Max Perutz and colleagues devised the approach that was to solve this riddle In 1958, J C Kendrew et al applied Perutz–s technique to produce the first three-dimensional images of any protein - myoglobin, the protein used by muscles to store oxygen

A three-dimensional model of the myoglobin molecule obtained by x-ray analysis.

Structure of Hen Egg-White Lysozyme: A Three-dimensional Fourier Synthesis at 2 A Resolution

Structure of hen egg-white lysozyme. A three-dimensional Fourier synthesis at 2 Angstrom resolution.

Structure of Myoglobin: A Three-Dimensional Fourier Synthesis at 2 Å. Resolution

A Partial Determination by X-ray Methods, and its Correlation with Chemical Data

Structure of Some Crystalline Lysozyme-Inhibitor Complexes Determined by X-Ray Analysis At 6 A Resolution

D. C. Phillips

Papers

A three-dimensional model of the myoglobin molecule obtained by x-ray analysis.

Structure of hen egg-white lysozyme. A three-dimensional Fourier synthesis at 2 Angstrom resolution.

Structure of Myoglobin: A Three-Dimensional Fourier Synthesis at 2 Å. Resolution

A Partial Determination by X-ray Methods, and its Correlation with Chemical Data

Structure of Some Crystalline Lysozyme-Inhibitor Complexes Determined by X-Ray Analysis At 6 Å Resolution