Four proteolytic bacteria were isolated and identified from a rotating biological contactor based on
Bacillus. The four isolates, Ni 26, 36, 39 and 49 were identified as B. vallismortis, B. subtilis, Aeromonas
hydrophila and B. amyloliquefaciens, resp...
Four proteolytic bacteria were isolated and identified from a rotating biological contactor based on
Bacillus. The four isolates, Ni 26, 36, 39 and 49 were identified as B. vallismortis, B. subtilis, Aeromonas
hydrophila and B. amyloliquefaciens, respectively, based on their biochemical properties and 16S rDNA
sequence analyses. The optimal proteolytic activity was observed in the temperature and pH ranges of
40-70ºC and 8.0-8.5, respectively. The proteolytic activities of all the isolates were partially inhibited by
phenylmethylsulfonylfluoride (PMSF), and the isolates Ni 26, Ni 39 and Ni 49 were inhibited by the
metalloprotease inhibitor, 1,10-phenanthroline. Zymographic analyses of the culture supernatants
revealed the presence of at least two proteases in all isolates.