Two separate extracellular proteolytic activities in four strains of O.oeni isolated from Argentinian
wine were reported [7]. The first took place in the early growth phase and the second had its maximum at
the end of growth phase in all strains. The production of the two proteolytic enzymes had different pH
and temperature optima and is affected by divalent cations. They were characterized and maximum
production was found with autoclaved grape juice as substrate [8]. The enzymes were thermostables and
their activities were unaltered by heating at 70°C for 15 min. Cysteine and ß-merchaptoethanol were
strong inhibitors of both enzymes, indicating the involvement of disulphide bridges.
Manca de Nadra and coworkers described that the protease II from O.oeni was able to liberate
detectable concentrations of amino acids from protein and polypeptide extracts from nitrogenous
macromolecular fraction (NMF) of white and red wines [9, 11].
Communicating Current Research and Educational Topics and Trends in Applied Microbiology
A. Méndez-Vilas (Ed.)