Plant Peptides and Peptidomics

Plant peptides, proteins smaller than 10 kDA (kilo Dalton), perform a wide range of functions in plants. A new review article published by the Plant Biotechnology Journal discusses these functions and introduces the use of peptidomics in identifying novel plant peptides.

Basically, plant peptides can be categorized into two categories. First are bioactive peptides produced upon degradation of larger precursor proteins, normally performing vast number of roles like cell to cell signaling, endurance against pests and pathogens and detoxification of heavy metals. The other group is composed of peptides produced by proteolysis during protein turnover. These peptides have no pronounced cellular effects, but some studies have implicated the group in nitrogen transport across cell membranes.

Peptidomics, a new branch of proteomics (large-scale study of proteins), is an efficient way of identifying new peptides. In this method, peptide pools are first separated by multiple liquid chromatography, after which they are identified by spectroscopy. It is a “top-down” version of proteomics, which only considers the peptidome. The characterization of the peptidome could have a profound effect on how plants can be modified for resistance to abiotic or biotic factors, as well as the development of plants that can produce health-related peptides.

The open access article is available at http://www.blackwell-synergy.com/doi/pdf/10.1111/j.1467-7652.2007.00315.x