RESUMO
Latex, a milky fluid found in several plants, is widely used for many purposes, and its proteins have been investigated by researchers. Many studies have shown that latex produced by some plant species is a natural source of biologically active compounds, and many of the hydrolytic enzymes are related to health benefits. Research on the characterization and industrial and pharmaceutical utility of latex has progressed in recent years. Latex proteins are associated with plants' defense mechanisms, against attacks by fungi. In this respect, there are several biotechnological applications of antifungal proteins. Some findings reveal that antifungal proteins inhibit fungi by interrupting the synthesis of fungal cell walls or rupturing the membrane. Moreover, both phytopathogenic and clinical fungal strains are susceptible to latex proteins. The present review describes some important features of proteins isolated from plant latex which presented in vitro antifungal activities: protein classification, function, molecular weight, isoelectric point, as well as the fungal species that are inhibited by them. We also discuss their mechanisms of action.
Assuntos
Antifúngicos/farmacologia , Quitinases/farmacologia , Látex/química , Peptídeo Hidrolases/farmacologia , Peroxidases/farmacologia , Lectinas de Plantas/farmacologia , Proteínas de Plantas/farmacologia , Antifúngicos/classificação , Antifúngicos/isolamento & purificação , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Quitinases/classificação , Quitinases/isolamento & purificação , Quitinases/fisiologia , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Ponto Isoelétrico , Testes de Sensibilidade Microbiana , Peso Molecular , Peptídeo Hidrolases/classificação , Peptídeo Hidrolases/isolamento & purificação , Peptídeo Hidrolases/fisiologia , Peroxidases/classificação , Peroxidases/isolamento & purificação , Peroxidases/fisiologia , Doenças das Plantas/microbiologia , Extratos Vegetais/química , Lectinas de Plantas/classificação , Lectinas de Plantas/isolamento & purificação , Lectinas de Plantas/fisiologia , Proteínas de Plantas/classificação , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/fisiologia , Plantas/químicaRESUMO
The anionic peroxidase associated with the suberization response in potato (Solanum tuberosum L.) tubers during wound healing has been purified and partially characterized at the biochemical level. It is a 45-kD, class III (plant secretory) peroxidase that is localized to suberizing tissues and shows a preference for feruloyl (o-methoxyphenol)-substituted substrates (order of substrate preference: feruloyl > caffeoyl > p-coumaryl approximately syringyl) such as those that accumulate in tubers during wound healing. There was little influence on oxidation by side chain derivatization, although hydroxycinnamates were preferred over the corresponding hydroxycinnamyl alcohols. The substrate specificity pattern is consistent with the natural substrate incorporation into potato wound suberin. In contrast, the cationic peroxidase(s) induced in response to wound healing in potato tubers is present in both suberizing and nonsuberizing tissues and does not discriminate between hydroxycinnamates and hydroxycinnamyl alcohols. A synthetic polymer prepared using E-[8-(13)C]ferulic acid, H(2)O(2), and the purified anionic enzyme contained a significant amount of cross-linking through C-8, albeit with retention of unsaturation.