Planta Med 2005; 71(3): 244-248
DOI: 10.1055/s-2005-837824
Original Paper
Biochemistry and Molecular Biology
© Georg Thieme Verlag KG Stuttgart · New York

Isolation of Two Plant Proteinases in Latex from Carica candamarcensis Acting as Mitogens for Mammalian Cells

Marco Túlio R. Gomes1 , Vanessa J. Mello2 , Kelly C. Rodrigues1 , Marcelo P. Bemquerer1 , Miriam T. P. Lopes2 , Vitor M. Faça3 , Carlos E. Salas1
  • 1Departamentos de Bioquímica e Imunologia, Instituto de Ciências Biológicas, UFMG, Belo Horizonte, Brasil
  • 2Departamentos de Farmacologia, Instituto de Ciências Biológicas, UFMG, Belo Horizonte, Brasil
  • 3Centro de Química de Proteínas, Faculdade de Medicina de Ribeirão Preto, USP, Ribeirão Preto, Brasil
Weitere Informationen


Received: May 17, 2004

Accepted: October 24, 2004

15. März 2005 (online)


In a prior study we showed evidence that latex from Carica candamarcensis contains a protein fraction that stimulates mammalian cell proliferation. In this report we describe the isolation of two proteinases responsible for this effect. Both proteinases (P1, P2) display a relative mass of 23 kDa and following chromatographic purification stimulate proliferation of fibroblastic and epithelial cells. P2 added to L929 fibroblasts at 2.5 nM enhances proliferation by 60 %. We further demonstrate that its cellular effect is linked to an increase in activity of Erk2, a component of the MAP kinase pathway. To our knowledge, this is the first known plant proteinase to exert a proliferative effect in mammalian cells. This novel mitogenic property attributed to a purified cysteine proteinase may explain some of the therapeutic actions attributed to these enzymes.


Carlos E Salas, PhD

Instituto de Ciências Biológicas

Universidade Federal de Minas Gerais

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Belo Horizonte

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