The biopolymers of all living organisms that were analyzed in the course of the past 150 years consist of homochiral monomer sequences, what means that all monomer units belong to the same class of enantiomers. Peptides and proteins of most multicellular organisms consist of L-prAAs, and only several fungi and microorganisms synthesize small amounts of peptides containing one or (rarely) two D-amino acids. The poisonous cyclic peptide phalloidin produced by the mushroom amanita phalloides is the most widely known example of a peptide containing a D-amino acid (D-Thr). All polysaccharides and the ribose and deoxy-ribose units in RNA and DNA exclusively consist of D-sugars. Poly(ß-hydroxybutyrate), a polyester produced as food reserve by numerous bacteria also consist of D-units. Natural rubber, which does not contain chiral building blocks, is made up by a perfect sequence of one geometrical isomer, the cis-isoprene unit, whereas other plants produce perfect poly(trans-isoprene).