CHAPTER 24 – Evolution of Protein Molecules

Inference of macromolecular assemblies from crystalline state.

On the Nature of Allosteric Transitions: A Plausible Model

Solvent content of protein crystals.

Stanford Moore, William Stein, and Anfinsen were awarded the Nobel Prize in Chemistry in 1972 for \"their contribution\n to the understanding of the connection between chemical structure and catalytic activity of the active center of the ribonuclease\n molecule.\" In his Nobel Lecture, Anfinsen provided a sketch of the rich history of research that provided the foundation\n for his work on protein folding and the \"Thermodynamic Hypothesis,\" and outlined potential avenues of current and\n future scientific exploration.

https://web.iitd.ac.in/~amittal/1973_Anfinsen_Science.pdf

Principles that Govern the Folding of Protein Chains

A chromosomal translocation in a T-cell leukemia involving the short arm of human chromosome 11 at band 11p15 disrupts the rhombotin gene. This gene encodes a protein with duplicated cysteine-rich regions called LIM domains, which show homology to zinc-binding proteins and to iron-sulfur centers of ferredoxins. Two homologues of the rhombotin gene have now been isolated. One of these, designated Rhom-2, is located on human chromosome 11 at band 11p13, where a cluster of T-cell leukemia-specific translocations occur; all translocation breakpoints at 11p13 are upstream of the Rhom-2 gene. Human and mouse Rhom-2 are highly conserved and, like rhombotin, encode two tandem cysteine-rich LIM domains. Rhom-2 mRNA is expressed in early mouse development in central nervous system, lung, kidney, liver, and spleen but only very low levels occur in thymus. The other gene, designated Rhom-3, is not on chromosome 11 but also retains homology to the LIM domain of rhombotin. Since the Rhom-2 gene is such a common site of chromosomal damage in T-cell tumors, the consistency of translocations near the rhombotin gene was further examined. A second translocation adjacent to rhombotin was found and at the same position as in the previous example. Therefore, chromosome bands 11p15 (rhombotin) and 11p13 (Rhom-2) are consistent sites of chromosome translocation in T-cell leukemia, with the 11p15 target more rarely involved. The results define the rhombotin gene family as a class of T-cell oncogenes with duplicated cysteine-rich LIM domains.

The rhombotin family of cysteine-rich LIM-domain oncogenes: distinct members are involved in T-cell translocations to human chromosomes 11p15 and 11p13.

Haem-haem interaction consists of a change of tension at the haems, caused by a transition between two alternative quaternary structures of the protein. Dr Perutz describes how spin changes that accompany reaction with ligands alter the oxygen affinity of the haems.

Nature of Haem–Haem Interaction

Structure Of Haeemoglobin: A Three-Dimensional Fourier Synthesis of Reduced Human Haemoglobin at 5.5 A Resolution

Max F. Perutz

Papers

The rhombotin family of cysteine-rich LIM-domain oncogenes: distinct members are involved in T-cell translocations to human chromosomes 11p15 and 11p13.

Nature of Haem–Haem Interaction

Structure of haemoglobin. a three-dimensional fourier synthesis of reduced human haemoglobin at 5-5 a resolution.

Structure and mechanism of haemoglobin

An X-ray study of azide methaemoglobin