Production of phosphohydrolases by Nicotiana tabacum 1507 cell suspension culture

The time course of growth, biosynthesis and secretion of different phosphoh ydrolytic activities by Nicotiana tabacum 1507 cell suspension culture were investigated. It was established that the cell culture under study biosynt hesised large amounts of phosphohydrolytic activities during the linear pha se of growth for a relatively short period (between the 2nd and 5th days of cultivation). The highest enzyme activity was determined with bis-pNPP whi ch is non-specific substrate for phosphodiesterases and for some nucleases (116.10(3) U/L at pH 5.7 and 51.10(3) U/L at pH 8.0). The different phospho hydrolytic activities were distingnished using specific substrates at pH 5. 7 (20.10(3) U/L - 5'-phosphodiesterases, 18,8.10(3) U/L - 3'-phosphodiester ases and 15,5.10(3) U/L - phosphomonoesterases) and at pH 8.0 (10,2.10(3) U /L - 5'-phosphodiesterases, 9,5.10(3) U/L - 3'-phosphodiesterases and 6,4.1 0(3) U/L - phosphomonoesterases).