A soluble Escherichia coli protease has been identified and purified to homogeneity. The protease cleaves glutamine synthetase which has been modified by mixed function oxidation; native glutamine synthetase is not a substrate. Using [14C]glutamine synthetase as a substrate (prepared by growing E. coli on 14C-labeled amino acids), protease activity was assayed by determining the release of tric...

Mango peel is a good source of protease but remains an industrial waste. This study focuses on the optimization of polyethylene glycol (PEG)/dextran-based aqueous two-phase system (ATPS) to purify serine protease from mango peel. The activity of serine protease in different phase systems was studied and then the possible relationship between the purification variables, namely polyethylene glyco...

the impact of three different fabaceous host plants including cowpea (vigna unguiculata), chickpea (cicer arietinum), and mung bean (vigna radiata) seeds was investigated using biochemical approaches on possible changes of gut proteolytic activity of the cowpea weevil, callosobruchus maculatus at 30±1˚c and 70±5% rh and a photoperiod of 8:16 (l:d). results revealed that ph of 4-5 and 9 was opti...

Proteases, one among the three largest groups of industrial enzymes, accounts for about 60% of the total worldwide sale of enzymes from biological sources since they possess almost all characteristics desired for their biotechnological applications (Adinarayana et al., 2003). Among the various proteases, bacterial protease was the most significant compared with animal, fungi and plant protease....

Escherichia coli signal peptide peptidase A (SppA) is a serine protease which cleaves signal peptides after they have been proteolytically removed from exported proteins by signal peptidase processing. We present here results of site-directed mutagenesis studies of all the conserved serines of SppA in the carboxyl-terminal domain showing that only Ser 409 is essential for enzymatic activity. Al...