Production of phosphohydrolases by Nicotiana tabacum 1507 cell suspension culture

The time course of growth, biosynthesis and secretion of different phosphohydrolytic activities by Nicotiana tabacum 1507 cell suspension culture were investigated. It was established that the cell culture under study biosynthesised large amounts of phosphohydrolytic activities during the linear phase of growth for a relatively short period (between the 2nd and 5th days of cultivation). The highest enzyme activity was determined with bis-pNPP which is non-specific substrate for phosphodiesterases and for some nucleases (116.103 U/L at pH 5.7 and 51.103 U/L at pH 8.0). The different phosphohydrolytic activities were distingnished using specific substrates at pH 5.7 (20.103 U/L – 5′-phosphodiesterases, 18,8.103 U/L – 3′-phosphodiesterases and 15,5.103 U/L – phosphomonoesterases) and at pH 8.0 (10,2.103 U/L – 5′-phosphodiesterases, 9,5.103 U/L – 3′-phosphodiesterases and 6,4.103 U/L – phosphomonoesterases).