ShellsHelices appear at every anatomical level across the nine (or so) orders of magnitude that span the range of size between molecules and the biggest organisms. They provide solutions to any number of the challenges of growth and form, structure and function including significantly movement, that evolution has thrown up. This essay explores the helix both as an abstract mathematical idea, with its stark elegance, simplicity and economy, and the ‘real’ helical structures that contribute to the richness and complexity of the living world – and the relationship between them. Helical structures are so pervasive that the helix can perhaps be regarded as providing a unifying and even necessary structural principle for life. The helical idea goes a long way to explaining why life at its most fundamental level of genes and proteins depends on two classes of small enantiomeric molecules, amino acids and nucleotides, significantly the molecules in each of the two classes all possessing the same hand. Life’s apparent requirement for helical symmetry at the deep molecular level forces the uniformity. See also Protein Quaternary Structure: Symmetry Patterns

MoleculeArticles relevant to Helices

Molluscs, Molecules and Staircases: Helix Magazine, volume 2, Issue 1, 1993

A Handle on Handedness: News and Views, Nature, 19 July 1990

Helical Evolution - A Cause for Reflection: News and Views, Nature, 19 December 1987

A Ciliate Through the Looking Glass: News and Views, Nature, 6 July 1989

Kinky Variations of Collagen: News and views, Nature, 7 August 1986

Reflections on the Ambivalent Helix: Experientia, October 1989

Handedness of Biological Molecules: Biological Asymmetry and Handedness, CIBA Foundation Symposium 162, Autumn 1991

Helical Imperative - Paradigm of Growth, Form and Function: Encyclopaedia of Life Sciences (ELS) John Wiley & Sons, Chichester, June 2010

Collagen: the Anatomy of a Protein: Institute of Biology, Studies in Biology No 73, 1980