Planta Med 2012; 78 - PI266
DOI: 10.1055/s-0032-1320953

Mauritanicain – a new serine protease from the latex of Euphorbia mauritanica L

M Flemmig 1, A Domsalla 1, H Rawel 2, MF Melzig 1
  • 1Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Straße 2+4, Berlin, 14195, Germany
  • 2Institute for Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114–116, Nuthetal, 14558, Germany

A new protease called Mauritanicain was isolated from the latex of Euphorbia mauritanica L. (Euphorbiaceae), with a high proteolytic activity against casein. The activity was only inhibited by specific serine protease inhibitors, classifying it to the serine protease family. It is stable at temperatures from 20–90°C with an optimum in activity at 55–60°C and pH 6.5–7.5. The protease with a molecular weight of about 95 kDa shows a preference to cleave its substrates (exemplarily shown for β-lactoglobulin) behind the amino acids lysine (K), leucine (L) and alanine (A).

Fig.1: Sequence of β-lactoglobuline (horse heart) and the theoretic cropped pieces after a digestion after L, K, A; sequence coverage: 90.7%